2020 Volume 31 Issue 1

Supramolecular polymers fabricated by orthogonal self-assembly based on multiple hydrogen bonding and macrocyclic host-guest interactions
Xiao Tangxin , Zhou Ling , Sun Xiao-Qiang , Huang Feihe , Lin Chen , Wang Leyong
2020, 31(1): 1-9  doi: 10.1016/j.cclet.2019.05.011
[Abstract](69) [FullText HTML] [PDF 1216KB](15)
Supramolecular polymers constructed by orthogonal self-assembly based on multiple hydrogen bonding and macrocyclic host-guest interactions have received increasing attention due to their elegant structures, outstanding properties, and potential applications. Hydrogen bonding endows these supramolecular polymers with good adaptability and reversibility, while macrocyclic host-guest interactions give them good selectivity and versatile stimuli-responsiveness. Therefore, functional supramolecular polymers fabricated by these two highly specific, noninterfering interactions in an orthogonal way have shown wide applications in the fields of molecular machines, electronics, soft materials, etc. In this review, we discuss the recent advances of functional supramolecular polymers fabricated by orthogonal self-assembly based on multiple hydrogen bonding and host-guest interactions. In particular, we focus on crown ether- and pillar[n]arene-based supramolecular polymers due to their compatibility with multiple hydrogen bonds in organic solution. The fabrication strategies, interesting properties, and potential applications of these advanced supramolecular materials are mainly concerned.
Progress on intelligent hydrogels based on RAFT polymerization: Design strategy, fabrication and the applications for controlled drug delivery
Xian Caihong , Yuan Qijuan , Bao Ziting , Liu Guiting , Wu Jun
2020, 31(1): 19-27  doi: 10.1016/j.cclet.2019.03.052
[Abstract](75) [FullText HTML] [PDF 1052KB](6)
Although intelligent hydrogels have shown bright potential application in biomedical fields, they were prepared by conventional methods and still face many serious challenges, such as uncontrollable stimulus-response and low response sensitivity. Recently, RAFT polymerization provides a versatile strategy for the fabrication of intelligent hydrogels with improved stimulus-response properties, owing to the ability to efficiently construct hydrogel precursors with well-defined structure, such as block copolymer, graft copolymer, star copolymer. In this review, we summarized the recent progress on intelligent hydrogels based on RAFT polymerization with emphasis on their fabrication strategies and applications for controlled drug delivery.
N2O emission in partial nitritation-anammox process
Li Li , Ling Yu , Wang Haiyan , Chu Zhaosheng , Yan Guokai , Li Zewen , Wu Tong
2020, 31(1): 28-38  doi: 10.1016/j.cclet.2019.06.035
[Abstract](77) [FullText HTML] [PDF 1003KB](4)
Nitrous oxide (N2O) is one of the significant greenhouse gases, and partial nitritation-anammox (PNA) process emits higher N2O than traditional nitrogen removal processes. N2O production in PNA mainly occurs in three different pathways, i.e., the ammonia oxidizing bacteria (AOB) denitrification, the hydroxylamine (NH2OH) oxidation and heterotrophic denitrifiers denitrification. N2O emission data vary significantly because of the different operational conditions, bioreactor configurations, monitoring systems and quantitative methods. Under the common operational parameter scopes of PNA, N2O emission via NH2OH oxidation dominates at relatively low dissolved oxygen (DO), low inorganic carbon (IC), high pH or low NO2- concentration, while N2O emission via AOB denitrification dominates at relative higher DO, higher IC, lower pH or higher NO2- concentration. AOB are highly enriched while nitriteoxidizing bacteria (NOB) are rarely found in partial nitritation process, and the order Nitrosomonadales of AOB is the dominant group and N2O producer. Anammox bacteria, AOB and certain amount of heterotrophic denitrifying bacteria are observed in the anammox process, the genus Denitratisoma and the heterotrophic denitrifying bacteria in the deep layer of anammox granules are the dominant N2O generation bacteria. In one-stage PNA reactors, anammox bacteria account for a large fraction of the biomass, AOB account for small portion, and NOB account for even less. The microbial community, diversity and N2O producers in one-stage PNA reactors are similar with those in two-stage PNA reactors. The dominant anammox bacteria, AOB and NOB in PNA are the species Candidatus Brocadia, the genera of Nitrotoga, Nitrospira and Nitrobacter, and the genus Nitrosomonas, respectively. The relations between N2O emission pathways and microbial communities need further study in the future.
TEMPO and its derivatives mediated reactions under transition-metal-free conditions
Zhuang Hongfeng , Li Heng , Zhang Shuai , Yin Yanbin , Han Feng , Sun Chao , Miao Chengxia
2020, 31(1): 39-48  doi: 10.1016/j.cclet.2019.06.027
[Abstract](63) [FullText HTML] [PDF 1185KB](9)
2, 2, 6, 6-Tetramethyl-1-piperidinyl-N-oxyl (TEMPO) and its derivatives as stable radicals can participate in many reactions. During the process, TEMPO and its derivatives could act not only as the substrates to capture or initiate new radical intermediates to provide new compounds but also as organic catalysts or oxidants for transformations of alkenes, alcohols, aldehydes and so on to synthesize various high valueadded compounds. In this review, we would introduce recent advances of the transformations of different substrates mediated by TEMPO and its derivatives under transition-metal-free conditions.
Recent advances in sulfenylation of C(sp3)-H bond under transition metal-free conditions
Xu Xin-Ming , Chen De-Mao , Wang Zu-Li
2020, 31(1): 49-57  doi: 10.1016/j.cclet.2019.05.048
[Abstract](78) [FullText HTML] [PDF 1576KB](4)
In recent years, the transition metal-free sulfenylation of C-H bond for C-S formation has been rapidly advanced and has become an eco-friendly synthetic tool for pharmacists and organic chemists. Various natural or bioactive molecules such as (hetero)arenes, olefins, carbonyl compounds, alkanes, have been employed for sulfenylating reactions. This review will focus on the recent five-year advances in C-S bond formation via direct sulfenylation of C(sp3)-H bonds under metal-free conditions and elaborate their mechanisms from a new perspective.
Advances in self-assembly and regulation of aromatic carboxylic acid derivatives at HOPG interface
Li Jianqiao , Zu Xiaoyi , Qian Yuxin , Duan Wubiao , Xiao Xunwen , Zeng Qingdao
2020, 31(1): 10-18  doi: 10.1016/j.cclet.2019.04.032
[Abstract](73) [FullText HTML] [PDF 1966KB](1)
Aromatic carboxylic acid self-assembly has been a hot research field for many scientists due to its strong coordination ability and flexible coordination mode. The hydrogen bond formed between aromatic carboxylic acids is a strong intermolecular force and has directionality and saturation, which plays a very important role in the self-assembly and regulation of aromatic carboxylic acids. In this review, we introduce surface organization formed by aromatic carboxylic acids with the aid of scanning tunneling microscopy (STM). These two-dimensional structures include molecular templates, host-guest systems, and photo-isomerization structures. We also emphasize the thermodynamics and dynamics, which are important research topics of current and future study.
Ir-catalyzed regiospecific mono-sulfamidation of arylquinazolinones
Feng Yadong , Zhang Zhenyue , Qi Fu , Yao Qiuhong , Huang Huabin , Shen Jinhai , Cui Xiuling
2020, 31(1): 58-60  doi: 10.1016/j.cclet.2019.05.013
[Abstract](59) [FullText HTML] [PDF 678KB](4)
An Ir-catalyzed selective mono-sulfamidation of 2-arylquinazolinones has been achieved with a low catalyst loading under mild conditions. A series of regioselective mono-sulfamided 2-arylquinazolinones were obtained in up to 90% yields. Compared with our previous work of constructing di-sulfamidated 2-arylquinazolinones, the mono-sulfamided products could be obtained selectively by changing the ratio of substrates, the loading of catalyst, acid additive, and reaction time.
Concise, enantioselective total syntheses of both the proposed and revised structures of (-)-versiquinazoline H
Wu Jiang-Feng , Huang Pei-Qiang
2020, 31(1): 61-63  doi: 10.1016/j.cclet.2019.06.043
[Abstract](66) [FullText HTML] [PDF 805KB](3)
The enantioselective total synthesis of the putative structure of versiquinazoline H and three diastereomers has been achieved, which allowed the revision of the stereochemistry of this natural product. This six-step total synthesis relied on the evolution of the strategy that we previously developed, which features a DMDO-triggered tandem reaction. The modification of the lactamization step resulted in a significant improvement of yield that ensured the efficient total synthesis.
Synthesis and application of a novel 9, 9-diethyl-1, 2-diaryl-1, 9-dihydrofluoreno[2, 3-d]imidazole for blue organic light emitting diode
Wang Xueying , Liao Zhangcheng , Wang Tianqi , Lin Haixia , Wang Zixing , Cui Yongmei
2020, 31(1): 64-66  doi: 10.1016/j.cclet.2019.05.044
[Abstract](64) [FullText HTML] [PDF 762KB](5)
Two novel 2-(4-(9, 9-disubstitued-9H-fluoren-2-yl)phenyl)-9, 9-diethyl-1-phenyl-1, 9-dihydrofluoreno-[2, 3-d]imidazole derivatives 2a and 2b were synthesized and characterized. Their photophysical and electrochemical properties, thermal stability property, and electroluminescence (EL) performance of 2b were investigated. The fabricated device based on 2b doping into 4, 4'-N, N'-dicarbazole-biphenyl (5%) as an emitter present a maximum brightness of 1272 cd/m2 at 4 V with the CIE coordinate of (0.1590, 0.0465).
Metal-free visible-light-induced oxidative cyclization reaction of 1, 6-enynes and arylsulfinic acids leading to sulfonylated benzofurans
Wang Leilei , Zhang Min , Zhang Yulong , Liu Qishun , Zhao Xiaohui , Li Jiang-Sheng , Luo Zidan , Wei Wei
2020, 31(1): 67-70  doi: 10.1016/j.cclet.2019.05.041
[Abstract](117) [FullText HTML] [PDF 883KB](5)
A new and convenient visible-light-induced method has been developed for the synthesis of sulfonylated benzofurans via oxidative cyclization reaction of 1, 6-enynes and arylsulfinic acids. This reaction was carried out under metal-free and mild conditions, in which the C-S, C-C and C=O bonds could be sequentially formed in one pot operation.
Synthesis of Z-scheme g-C3N4 nanosheets/Ag3PO4 photocatalysts with enhanced visible-light photocatalytic performance for the degradation of tetracycline and dye
Ding Meng , Zhou Juanjuan , Yang Hongcen , Cao Ruya , Zhang Shouwei , Shao Minghui , Xu Xijin
2020, 31(1): 71-76  doi: 10.1016/j.cclet.2019.05.029
[Abstract](58) [FullText HTML] [PDF 1119KB](7)
Graphene-like C3N4/Ag3PO4 photocatalysts are synthesized by calcination and solutions precipitating method. The obtained g-C3N4/Ag3PO4 composites display excellent photocatalytic activity for the degradation of methylene orange (MO), rhodamine B (RhB) and tetracycline (TC) under visible light irradiation. The solutions containing RhB (10 mg/L) and MO (10 mg/L) can be efficiently degraded within 15 min and 30 min. Especially, nearly 80% of TC (50 mg/L) is degraded within 20 min, which are much better than those of pure g-C3N4 nanosheets and Ag3PO4, implying that strong interaction and reasonable energy band alignment in the contact interface can effectively transfer the carries. Furthermore, the g-C3N4/Ag3PO4 composites exhibit the improved stability, and only a slight decrease is observed after three recycling runs. Moreover, the impact of inorganic ions and PH values on the degradation performance is rather small. The Z-scheme photocatalytic mechanism of the g-C3N4/Ag3PO4 composites based on the active species trapping experimental is proposed. This work demonstrates the promising applications of the g-C3N4/Ag3PO4 composites in environmental issues.
Unimolecular artificial transmembrane channel with terminal dihydrogen phosphate groups showing transport selectivity for ammonium
Chen Jian-Yu , Xiao Qi , Behera Harekrushna , Hou Jun-Li
2020, 31(1): 77-80  doi: 10.1016/j.cclet.2019.05.009
[Abstract](64) [FullText HTML] [PDF 768KB](2)
A new artificial transmembrane channel molecule bearing dihydrogen phosphate groups has been synthesized. The terminal dihydrogen phosphate groups enable the channel to be highly negatively charged at both ends of the channel structures. The artificial channel could incorporate into the lipid bilayer efficiently under low concentration. The channel displays high NH4+/K+ selectivity due to the electrostatic interaction and hydrogen bonding between NH4+ and the terminal dihydrogen phosphate groups.
Construction of [1]rotaxanes with pillar[5]arene as the wheel and terpyridine as the stopper
Zhao Ling-Ling , Han Ying , Yan Chao-Guo
2020, 31(1): 81-83  doi: 10.1016/j.cclet.2019.04.024
[Abstract](65) [FullText HTML] [PDF 756KB](3)
The condensation reaction of ω-aminoalkyleneamide-functionalized pillar[5]arenes with 2-(4-([2, 2':6', 2''-terpyridin]-4'-yl)phenoxy)acetic acid or 4-(4-([2, 2':6', 2''-terpyridin]-4'-yl)phenoxy)butanoic acid in dry chloroform at room temperature under the catalysis of HOBT/EDCl resulted in novel pillar[5]arene diamido-bridged terpyridine derivatives. 1H NMR and 2D NOESY spectra clearly indicated that the interesting [1]rotaxanes were formed by longer alkylene such as propylene, butylene and hexylenediamido chains threading into the cavity of the pillar[5]arene and with larger terpyridine acting as the stopper. However, the shorter ethylenediamido chain only exists outer of cavity of pillar[5]arene and the molecule exist on free form.
C-S coupling with nitro group as leaving group via simple inorganic salt catalysis
Xuan Maojie , Lu Chunlei , Lin Bo-Lin
2020, 31(1): 84-90  doi: 10.1016/j.cclet.2019.07.012
[Abstract](52) [FullText HTML] [PDF 1958KB](2)
An efficient and practical synthetic protocol to synthesize nonsymmetrical aryl thioethers by nucleophilic aromatic substitution (SNAr) reaction of nitroarenes by thiols with potassium phosphate as the catalyst is described. Various moderate to strong electron-withdrawing functional groups are tolerated by the system to provide thioethers in a good to excellent yields. We also showed that the present method allows access to 3 drug examples in a short reaction time. Finally, mechanistic studies suggest that the reaction may form the classic Meisenheimer complex through a two-step additionelimination mechanism.
Coumarinocoumarin-based fluorescent probe for the sensitive and selective detection of hydrazine in living cells and zebra fish
Fang Qian , Yang Lei , Xiong Haiqing , Han Shaohui , Zhang Yun , Wang Jingpei , Chen Wenqiang , Song Xiangzhi
2020, 31(1): 129-132  doi: 10.1016/j.cclet.2019.04.021
[Abstract](67) [FullText HTML] [PDF 798KB](3)
A coumarinocoumarin-based fluorescent probe, JCCA, was developed for the detection of N2H4. JCCA exhibited a fast turn-on fluorescence enhancement in response to N2H4 with good selectivity, sensitivity and a detection limit of 7.4 nmol/L. Significantly, JCCA displayed a good capability for visualizing N2H4 in living cells and zebra fish.
A novel off-on fluorescent probe for specific detection and imaging of cysteine in live cells and in vivo
Zhang Baoxin , Zhang Haijuan , Zhong Miao , Wang Song , Xu Qianhe , Cho Dong-Hyung , Qiu Hongdeng
2020, 31(1): 133-135  doi: 10.1016/j.cclet.2019.05.061
[Abstract](65) [FullText HTML] [PDF 773KB](4)
Cysteine (Cys) plays a pivotal role in many physiological and pathological processes, including detoxification and protein synthesis. The abnormal levels of Cys are linked to many diseases. In this study, a novel red-emitting off-on fluorescent probe Cys-TCF was masterly constructed for discriminative detection of Cys. After a series of experimental assessment, Cys-TCF displayed higher selectivity and sensitivity for Cys over other biothilols with a low detection limit (0.04 μmol/L). More notably, the probe was also successfully applied to image Cys in live cells and live zebrafishes with low cytotoxicity.
Synthesis and biological evaluation of piperidyl benzimidazole carboxamide derivatives as potent PARP-1 inhibitors and antitumor agents
Zhang Xinwei , Zhang Cunlong , Tang Lin , Lu Kuan , Zhao Huan , Wu Weibin , Jiang Yuyang
2020, 31(1): 136-140  doi: 10.1016/j.cclet.2019.04.045
[Abstract](57) [FullText HTML] [PDF 782KB](5)
We have synthesized a series of compounds based on a piperidyl benzimidazole carboxamide structure, and tested their PARP-1 inhibitory activity, as well as cellular inhibitory activity. Some of them show great potency as PARP-1 inhibitors and antitumor activity, which are valuable for further research. In addition, the predicted ADME properties and proposed binding mode with PARP-1 of the compounds were obtained via computational simulation.
Synthesis, bioactivities and 3D-QSAR of novel avermectin B2a aglycon derivatives
Huang Fangfang , Ling Huan , Li Jiao , Lu Sen , Liu Weijie , Li Qingshan , Xu Fengbo
2020, 31(1): 141-144  doi: 10.1016/j.cclet.2019.03.054
[Abstract](60) [FullText HTML] [PDF 822KB](4)
Fourteen avermectin B2a aglycon derivatives were designed and synthesized after removing the oleandrose disaccharide of avermectin B2a. Their structures were characterized by 1H NMR, 13C NMR, HMRS. Preliminary bioassays indicated that these compounds exhibited good insecticidal activity against diamondback moth at 200 mg/L, with mortality no less than 90%. Compounds 10b, 12a, 12c, 17 demonstrated good acaricidal activity against the adult mites, larvae, and good inhibition rate of hatching to mite eggs of Tetranychus cinnabarinus. Compounds 5, 10b, 10c exhibited excellent fungicidal activity against fourteen fungal pathogens in vitro. 3D-QSAR analysis showed that the fungicidal activity of avermectin B2a aglycon derivatives would be increased when a negatively charged and bulky group was introduced at 13-position, which will be instructive for the further modification of avermectin B2a aglycon.
Dual functional AgNPs-M13 phage composite serves as antibacterial film and sensing probe for monitoring the corrosion of chromium-containing dental alloys
Yang Ting , Li Na , Wang Xiaoyan , Zhai Jian , Hu Bo , Chen Mingli , Wang Jianhua
2020, 31(1): 145-149  doi: 10.1016/j.cclet.2019.07.026
[Abstract](66) [FullText HTML] [PDF 832KB](1)
The preparation of silver nanoparticles (AgNPs) with microbe or plant tissues as bio-template offers green approach, while it suffers from low harvest and purification is needed. Herein, we propose a facile protocol for one-pot preparation of AgNPs using M13 phage as bio-template by simply mixing AgNO3 solution with alkali M13 phage. In the obtained AgNPs-M13 phage composite, Cr(Ⅲ) selectively coordinates with the amino residues on phage surface and leads to the aggregation of AgNPs through the bridging of M13 phages. This makes it feasible for colorimetric sensing of Cr(Ⅲ) by measuring the absorbance ratio of AgNPs at 600 and 405 nm, which provides a LOD of 14 nmol/L. The composite also showed favorable bactericidal activity for both Gram-positive and Gram-negative bacteria, making it a promising candidate as antibacterial film in chromium-containing dental alloys and meanwhile serve as a sensing probe for monitoring the corrosion of the dental alloys.
FTIR-ATR study for adsorption of trypsin in aqueous environment on bare and TiO2 coated ZnSe surfaces
Guo Chune , Guo Xiaomi , Chu Wubo , Jiang Nan , Li He
2020, 31(1): 150-154  doi: 10.1016/j.cclet.2019.04.067
[Abstract](54) [FullText HTML] [PDF 1743KB](5)
Undesired adsorption of proteins brings big troubles to marine structures. The settled proteins change the physical and chemical properties of the surfaces, which allow marine fouling organisms to settle down on the structures. Therefore, to understand the adsorption mechanism of proteins is very helpful to find an environment-friendly solution against biofouling. Many approaches have been developed to study protein adsorption, but most of them are insufficient to give the chemical interaction information between proteins and surfaces. Fourier transform infrared spectroscopy with attenuated total reflection (FTIR-ATR) is an efficient, fast and non-destructive method for in situ surface measurement, which greatly minimizes the interference of water to infrared spectra, because of the very small depth of penetration of the evanescent wave. In this paper, an in situ FTIR-ATR technology was used to investigate the adsorption process of trypsin on a bare ZnSe surface and on a TiO2 coated ZnSe surface, and the effect of calcium cation strength and ultraviolet light irradiation on the secondary structure of trypsin were also evaluated. FTIR spectra of trypsin showed that Amide Ⅰ band red shift and Amide Ⅱ band blue shift in aqueous environment on both surfaces compared with the dry trypsin powder, and the addition of calcium cations further changed the Amide bands position, which indicated that the change of the secondary structure could be interfered by the environment. The hydrogen bond formation between water and trypsin, the interaction between surface and trypsin, the interaction between hydrated calcium cations and trypsin, are major factors to change the secondary structure of trypsin, and UV light irradiation also showed its influence for the secondary structure.
A novel aptasensor strategy for protein detection based on G-quadruplex and exonuclease Ⅲ-aided recycling amplification
Shi Huan , Jin Tian , Zhang Jiewen , Huang Xiaoting , Tan Chunyan , Jiang Yuyang , Tan Ying
2020, 31(1): 155-158  doi: 10.1016/j.cclet.2019.06.020
[Abstract](55) [FullText HTML] [PDF 775KB](2)
The detection of biomarkers is of great significance in the diagnosis of numerous diseases, especially cancer. Herein, we developed a sensitive and universal fluorescent aptasensor strategy based on magnetic beads, DNA G-quadruplex, and exonuclease Ⅲ (Exo Ⅲ). In the presence of a target protein, a label-free single strand DNA (ssDNA) hybridized with the aptamer was released as a trigger DNA due to specific recognition between the aptamer and target. Subsequently, ssDNA initiates the Exo Ⅲ-aided recycling to amplify the fluorescence signal, which was caused by N-methylmesoporphyrin Ⅸ (NMM) insertion into the G-quadruplex structure. This proposed strategy combines the excellent specificity between the aptamer and target, high sensitivity of the fluorescence signal by G-quadruplex and Exo Ⅲaided recycling amplification. We selected (50-1200 nmol/L) MUC1, a common tumor biomarker, as the proof-of-concept target to test the specificity of our aptasensor. Results reveal that the sensor sensitively and selectively detected the target protein with limits of detection (LODs) of 3.68 and 12.83 nmol/L in buffer solution and 10% serum system, respectively. The strategy can be easily applied to other targets by simply substituting corresponding aptamers and has great potential in the diagnosis and monitoring of several diseases.
Asymmetric polymerase chain reaction and loop-mediated isothermal amplification (AP-LAMP) for ultrasensitive detection of microRNAs
Wang Ruili , Lan Ling , Liu Li , Cheng Liang
2020, 31(1): 159-162  doi: 10.1016/j.cclet.2019.05.003
[Abstract](74) [FullText HTML] [PDF 963KB](3)
In this manuscript, we first report an ultrasensitive detection assay of microRNA by combing asymmetric polymerase chain reaction (A-PCR) and loop-mediated isothermal amplification (LAMP) technology. Using A-PCR obtained an extended single strand to form LAMP stem-loop structure under isothermal amplification conditions. We used miRNAs as a loop primer probe in LAMP reaction and completed its ultrasensitive and rapid detection. The established method furnished a fast, specific and efficient detection of target miRNA with a detection limit as low as 10 amol/L in 90 min.
Site-specific protein modification by genetic encoded disulfide compatible thiols
Ling Xinyu , Chen Heqi , Zheng Wei , Chang Liying , Wang Yong , Liu Tao
2020, 31(1): 163-166  doi: 10.1016/j.cclet.2019.04.075
[Abstract](65) [FullText HTML] [PDF 890KB](4)
Cysteine chemistry provides a low cost and convenient way for site-specific protein modification. However, recombinant expression of disulfide bonding containing protein with unpaired cysteine is technically challenging and the resulting protein often suffers from significantly reduced yield and activity. Here we used genetic code expansion technique to introduce a surface exposed self-paired dithiol functional group into proteins, which can be selectively reduced to afford active thiols. Two compounds containing self-paired disulfides were synthesized, and their genetic incorporations were validated using green fluorescent proteins (GFP). The compatibility of these self-paired di-thiols with natural disulfide bond was demonstrated using antibody fragment to afford site-specifically labeled antibody. This work provides another valuable building block into the chemical tool-box for site-specific labeling of proteins containing internal disulfides.
Topography guiding the accelerated and persistently directional cell migration induced by vaccinia virus
Wang Cheng , Wang Ji , Fu Dandan , Yan Qiong , Pang Daiwen , Zhang Zhiling
2020, 31(1): 167-171  doi: 10.1016/j.cclet.2019.05.043
[Abstract](67) [FullText HTML] [PDF 1021KB](3)
The rapid transmission of vaccinia virus (VACV) in vivo is thought to be closely related to the cell migration induced by it. Cell migration involved in dynamic changes of cell-substrate adhesion and actin cytoskeleton organization, which can influence by the micro/nano-scale topographic structures that cells are naturally exposed to via contact guidance. However, migration behaviors of VACV-infected cells exposed to topographic cues are still unknown. Herein, we designed an open chip with microgrooved poly(dimethyl siloxane) (PDMS) substrate to explore the topography roles in VACV-induced cell migration. Differed from the random cell migration observed in traditional scratch assay on planar substrate, VACV-infected cells had a tendency to persistently migrate along the axis parallel to microgroove with increased velocity. Moreover, infected cells exhibited a dominant elongated protrusion aligned to the micro-grating axis compare to the shorter lamella extended in any direction on smooth substrate. Interestingly, the Golgi complex preferred to relocate behind the nucleus confined within the micro-grating axis in majority of infected migratory cells. The directional polarization of cells embodied in protrusion formation and Golgi reorientation was responsible for the directionally persistent migration behaviors induced by VACV on microgrooved substrate. Infected cells response to substrate topography, causing the actin-filled stretched protrusion containing numerous virions and accelerated movement is likely to facilitate direct and rapid spread of VACV. This work opens a window for us to understand the migration behaviors of infected cells in vivo, and also provides a cue for revealing the relationship between virus-induced cell migration and virus rapid spread.
A designed locked nucleic acid-based nanopore for discriminating ctDNA and its coexisting analogue ncDNA
Huang Yuqin , Lv You , Geng Jia , Xiao Dan , Zhou Cuisong
2020, 31(1): 172-176  doi: 10.1016/j.cclet.2019.05.033
[Abstract](50) [FullText HTML] [PDF 995KB](2)
Circulating tumor DNA (ctDNA), carrying tumor-specific sequence mutations, is a promising biomarker for classification, diagnosis and prognosis of cancers. However, there is still a great challenge in discriminating single-base difference between ctDNA and its coexisting analogue (normal circulating DNA, ncDNA) at a serum sample. A locked nucleic acid (LNA) probe combined with α-HL nanopore sensor was designed, which achieved a high signal-to-background ratio (SBR) of ~8.34×103, as well as a significant discrimination capability (~12.3 times) of single-base difference. The accurate discrimination strategy is label-free, convenient, selective and sensitive, which has great potential in the early diagnosis of diseases and biomedical research fields.
3DRGO-NiFe2O4/NiO nanoparticles for fast and simple detection of organophosphorus pesticides
Wei Zhenni , Li Huiqing , Wu Jing , Dong Yalei , Zhang Hongyi , Chen Hongli , Ren Cuiling
2020, 31(1): 177-180  doi: 10.1016/j.cclet.2019.05.031
[Abstract](68) [FullText HTML] [PDF 785KB](3)
The residues of organophosphorus pesticide (OPs) on fruits and vegetables pose a threat to human health, so it is very meaningful to explore simple and fast detect methods for OPs residual. In this work, nickel ferrite/nickel oxide nanoparticles co-loaded three-dimensional reduced graphene oxide (3DRGO-NiFe2O4/NiO NPs), as a new low cost nanocomposite, was prepared. Based on its high performance mimetic peroxidase activity, a colorimetric method for the detection of OPs has been developed. Dichlorvos was chosen as model compounds to evaluate the detection performance. The detection linear range for dichlorvos is from 50 mg/mL to 2.5×104 mg/mL with a detection limit of 10 mg/mL. Furthermore, a test paper can be developed based on the 3DRGO-NiFe2O4/NiO NPs for visual detection of dichlorvos, and the image information of the paper sensor can be converted into digital signal and quantitative detection by a smartphone. Notably, this method can also be used to detect dichlorvos in real samples, including vegetables and fruits. Thus, the developed naked assay holds great potential in simple, inexpensive and rapid detection of OPs in fruit and vegetable samples.
Synthesis of core-shell structured Au@Bi2S3 nanorod and its application as DNA immobilization matrix for electrochemical biosensor construction
Gao Feng , Song Juan , Zhang Bin , Tanaka Hidekazu , Gao Fei , Qiu Weiwei , Wang Qingxiang
2020, 31(1): 181-184  doi: 10.1016/j.cclet.2019.04.056
[Abstract](62) [FullText HTML] [PDF 799KB](2)
The core-shell structured Au@Bi2S3 nanorods have been prepared through direct in-situ growth of Bi2S3 at the surface of pre-synthesized gold nanorods. The product was characterized by X-ray diffraction, transmission electron microscopy and energy-dispersive X-ray spectroscopy. Then the obtained Au@Bi2S3 nanorods were coated onto glassy carbon electrode to act as a scaffold for fabrication of electrochemical DNA biosensor on the basis of the coordination of -NH2 modified on 5'-end of probe DNA and Au@Bi2S3. Electrochemical characterization assays demonstrate that the Au@Bi2S3 nanorods behave as an excellent electronic transport channel to promote the electron transfer kinetics and increase the effective surface area by their nanosize effect. The hybridization experiments reveal that the Au@Bi2S3 matrix-based DNA biosensor is capable of recognizing complementary DNA over a wide concentration ranging from 10 fmol/L to 1 nmol/L. The limit of detection was estimated to be 2 fmol/L (S/N=3). The biosensor also presents remarkable selectivity to distinguish fully complementary sequences from basemismatched and non-complementary ones, showing great promising in practical application.
A photosensitizer-loaded zinc oxide-polydopamine core-shell nanotherapeutic agent for photodynamic and photothermal synergistic therapy of cancer cells
Wu Ri , Wang Huizhen , Hai Luo , Wang Tianzheng , Hou Min , He Dinggeng , He Xiaoxiao , Wang Kemin
2020, 31(1): 189-192  doi: 10.1016/j.cclet.2019.05.004
[Abstract](55) [FullText HTML] [PDF 891KB](2)
In clinical cancer research, it is quite promising to develop multimodal synergistic therapeutic strategies. Photodynamic and photothermal synergistic therapy is a very desirable multimodal therapy strategy. Herein, we report a facile and simple method to construct a nanotherapeutic agent for photodynamic and photothermal therapy. This nanotherapeutic agent (ZnO@Ce6-PDA) is composed of a ZnO nanoparticle core, an interlayer of photosensitizer chlorin e6 (Ce6) and an outer layer of polydopamine (PDA). Due to the existence of Ce6, the ZnO@Ce6-PDA can efficiently generate singlet oxygen (1O2) under 660 nm laser irradiation. Moreover, the ZnO@Ce6-PDA can serve as a photothermal agent, because of the excellent photothermal conversion efficiency of the PDA coating layer in the presence of 780 nm laser. Experiment results demonstrated that the designed nanotherapeutic agent had outstanding phototoxicity upon the combination of laser irradiation at 660 and 780 nm. Thus, our work proves that the ZnO@Ce6-PDA is a promising photodynamic/photothermal dual-modal nanotherapeutic agent for enhanced cancer therapy.
A novel channel-wall engineering strategy for two-dimensional cationic covalent organic frameworks: Microwave-assisted anion exchange and enhanced carbon dioxide capture
Ding Yusen , Wang Yan , Su Yanjie , Yang Zhi , Liu Jiaqiang , Hua Xiaolin , Wei Hao
2020, 31(1): 193-196  doi: 10.1016/j.cclet.2019.05.012
[Abstract](76) [FullText HTML] [PDF 1003KB](7)
A novel channel-wall engineering strategy of the porous materials cationic covalent organic frameworks (COFs) is established based on rapid microwave-assisted anion exchange reaction and utilized to prepare a set of new COFs. Due to the interaction between the carbon dioxide (CO2) and the acetate anion, the resulting SJTU-COF-AcO shows greatly enhanced carbon dioxide capacity up to 1.7 times of the pristine COF. The effect of the counter anions to CO2 capacity in the cationic COFs is investigated for the first time, which demonstrates that our channel-wall engineering strategy is a promising way to tailor the property of COFs for high CO2 capacity.
New cyclopiane diterpenes with antiinflammatory activity from the sea sediment-derived fungus Penicillium sp. TJ403-2
Li Fengli , Sun Weiguang , Zhang Sitian , Gao Weixi , Lin Shuang , Yang Beiye , Chai Chenwei , Li Huaqiang , Wang Jianping , Hu Zhengxi , Zhang Yonghui
2020, 31(1): 197-201  doi: 10.1016/j.cclet.2019.04.036
[Abstract](61) [FullText HTML] [PDF 834KB](4)
Three new rare cyclopiane diterpenes (1-3), together with thirteen known compounds (4-16), were isolated and identified from a sea sediment-derived fungus Penicillium sp. TJ403-2. The planar and relative structures of compounds 1-3 were elucidated by HRESIMS, one- and two-dimensional NMR analyses, and their absolute configurations were further established by X-ray crystallography experiment. Compounds 1-3 were evaluated for the antiinflammatory activity against LPS-induced NO production, and compound 1 showed notable inhibitory potency with an IC50 value of 2.19±0.25 μmol/L, which was three fold lower than the positive control indomethacin (IC50=8.76±0.92 μmol/L). Further Western blot and immunofluorescence experiments demonstrated its mechanism of action to be that 1 inhibited the NF-ΚB-activated pathway, highlighting it as a promising starting point for the development of new antiinflammatory agents.
Detection protein biomarker with gold nanoparticles functionalized hollow mesoporous Prussian blue nanoparticles as electrochemical probes
Luo Jing , Li Ting , Yang Minghui
2020, 31(1): 202-204  doi: 10.1016/j.cclet.2019.05.051
[Abstract](52) [FullText HTML] [PDF 679KB](2)
Gold nanoparticles functionalized hollow mesoporous Prussian blue nanoparticles (Au@HMPB NPs) were synthesized and its peroxidase-like activity was explored for electrochemical probe. The Au@HMPB NPs can reduce H2O2 at low detection potential of -0.1 V with high sensitivity. After physically adsorption of antibodies onto the gold nanoparticle surface, the functionalized nanoparticles were turned into immuno-probe. The soluble α-chain of interleukin-2 (IL-2) receptor (sCD25) was chosen as a model protein biomarker to test the performance of the probe. sCD25 in the samples were captured and enriched by capture anti-CD25 antibody functionalized magnetic nanospheres. Detection antibody functionalized Au@HMPB can then be linked onto the nanospheres and generate electrochemical current towards H2O2 reduction. The electrochemical responses to 1 mmol/L H2O2 was increased with the increasing concentration of CD25.
Macroporous composite capacitive bioanode applied in microbial fuel cells
Wang Yuyang , Zheng Hongtao , Chen Ye , Wen Qing , Wu Jiansong
2020, 31(1): 205-209  doi: 10.1016/j.cclet.2019.05.052
[Abstract](59) [FullText HTML] [PDF 772KB](2)
Interfacial electron transfer between electroactive biofilm and the electrode was crucial step for microbial fuel cells (MFCs). A three-dimensional multilayer porous sponge coating with nitrogen-doped carbon nanotube/polyaniline/manganese dioxide (S/N-CNT/PANI/MnO2) electrode has been developed for MFC anode. Here, the S/N-CNT/PANI/MnO2 anode can function as a biocapacitor, able to store electrons generated from the degradation of organic substrate under the open circuit state and release the accumulated electrons upon requirement. Thus, the mismatching of the production and demand of the electricity can be overcome. Comparing with the sponge/nitrogen-doped carbon nanotube (S/N-CNT) bioanode, S/N-CNT/PANI/MnO2 capacitive bioanode displays a strong interaction with the microbial biofilm, advancing the electron transfer from exoelectrogens to the bioanode. The maximum power density of MFC with S/N-CNT/PANI/MnO2 capacitive bioanode is 1019.5 mW/m2, which is 2.2 and 5.8 times as much as that of S/N-CNT/MnO2 bioanode and S/N-CNT bioanode (470.7 mW/m2 and 176.6 mW/m2), respectively. During the chronoamperometric experiment with 60 min of charging and 20 min of discharging, the S/N-CNT/PANI/MnO2 capacitive bioanode was able to store 10743.9 C/m2, whereas the S/N-CNT anode was only able to store 3323.4 C/m2. With a capacitive bioanode, it is possible to use the MFC simultaneously for production and storage of electricity
A novel Mo-based oxide β-SnMoO4 as anode for lithium ion battery
Zheng Huiwen , Zhang Hailin , Fan Yu , Ju Ge , Zhao Hongbin , Fang Jianhui , Zhang Jiujun , Xu Jiaqiang
2020, 31(1): 210-216  doi: 10.1016/j.cclet.2019.03.048
[Abstract](66) [FullText HTML] [PDF 1066KB](3)
Recently, the development of new electrode materials for lithium-ion batteries (LIBs) has received intensive attention. As an important family of inorganic materials, mixed Mo-based transition metal oxides system is focused as anode materials. In the present work, a simple route has been adopted for the synthesis of layered-flake-like β-SnMoO4 Nano-assemblies, which have been explored as potential anode materials for the first time in lithium-ion battery (LIB). Overall, the current reports on metal molybdate as anode materials are still rarely. As the anode material for LIBs, it was observed that the fabricated anode is capable of delivering a steady state capacity of almost 400 mAh/g up to 300 cycles under the influence of 200 mA/g current density. Further, the anode material is suitable for use as a rated capacity anode because of its high current density tolerance. The present study can be further extended for the generation of a wide variety of other novel materials for multidisciplinary energy related applications.
Cotton-derived oxygen/sulfur co-doped hard carbon as advanced anode material for potassium-ion batteries
Baolin Xu , Shihan Qi , Fang Li , Xiaoxin Peng , Jinfeng Cai , Jiaojiao Liang , Jianmin Ma
2020, 31(1): 217-222  doi: 10.1016/j.cclet.2019.10.009
[Abstract](84) [FullText HTML] [PDF 995KB](1)
Hard carbon is regarded as promising anode materials for potassium-ion batteries (KIBs) owing to their low price and easy availability. However, the limited rate capability still needs to be improved. Herein, we demonstrate the fabrication of oxygen/sulfur co-doped hard carbon through a facile hydrolyzationsulfuration process of skimmed cotton. The simultaneous dopants significantly improve potassium ion diffusion rate. When served as the anode for KIBs, this hydrolyzed hard carbon delivered a high reversible capacity (409 mAh/g at 0.1 A/g), superior rate capability (135 mAh/g at 2 A/g) and excellent cyclability (about 120 mAh/g overt 500 cycles at 2 A/g). This work provides a facile strategy to prepare low-cost doped-hard carbon with superior potassium storage property.
Porous surfur-doped hard carbon for excellent potassium storage
Xuan Xie , Qi Shihan , Wu Daxiong , Wang Huaping , Li Fang , Peng Xiaoxin , Cai Jinfeng , Liang Jiaojiao , Ma Jianmin
2020, 31(1): 223-226  doi: 10.1016/j.cclet.2019.10.008
[Abstract](61) [FullText HTML] [PDF 977KB](2)
Hard carbon is promising anode for potassium-ion batteries (PIBs), however, the poor rate capability hinders its development as potential anode. To address this question, we design a sulfur-doped porous hard carbon (S-HC) for PIBs through the combination of structural design and composition adjustment. The as-designed S-HC exhibits a long cycling life with ~191 mAh/g after 300 cycles at 1 A/g, and an excellent rate capability with ~100 mAh/g at 5 A/g, which was attributed to its structural characteristics and compositions. The S-HC demonstrates to be promising anode in the future.
High-throughput model-building and screening of zeolitic imidazolate frameworks for CO2 capture from flue gas
Lixia Yang , Chao Shi , Lin Li , Yi Li
2020, 31(1): 227-230  doi: 10.1016/j.cclet.2019.04.025
[Abstract](60) [FullText HTML] [PDF 810KB](3)
To find potential zeolitic imidazolate frameworks (ZIFs) for CO2 capture from flue gas, we built 169, 898 ZIF models from 84, 949 hypothetical zeolite networks. By calculating their lattice energies, accessible volumes to CO2, the isosteric adsorption heat (Qst) of H2O, Henry's constant ratio (SKH) of CO2/N2, percent regenerability (R%), CO2 working capacity (ΔNCO2), CO2/N2 adsorption selectivity (SCO2/N2) and adsorbent performance score (APS), we identified 49 hydrophobic ZIF structures that might outplay already-realised ZIFs built from the same imidazolate linkers for CO2 capture from flue gas.
Integrating bimetallic AuPd nanocatalysts with a 2D aza-fused π-conjugated microporous polymer for light-driven benzyl alcohol oxidation
Li Yunong , Wang Lei , Low Jingxiang , Wu Di , Hu Canyu , Jiang Wenbin , Ma Jun , Wang Chengming , Long Ran , Song Li , Xu Hangxun , Xiong Yujie
2020, 31(1): 231-234  doi: 10.1016/j.cclet.2019.04.022
[Abstract](74) [FullText HTML] [PDF 820KB](4)
Efficient catalytic system with low energy consumption exhibits increasing importance due to the upcoming energy crisis. Given this situation, it should be an admirable strategy for reducing energy input by effectively utilizing incident solar energy as a heat source during catalytic reactions. Herein, aza-fused π-conjugated microporous polymer (aza-CMP) with broad light absorption and high photothermal conversion efficiency was synthesized and utilized as a support for bimetallic AuPd nanocatalysts in light-driven benzyl alcohol oxidation. The AuPd nanoparticles anchored on aza-CMP (aza-CMP/AuxPdy) exhibited excellent catalytic performance for benzyl alcohol oxidation under 50 mW/cm2 light irradiation. The improved catalytic performance by the aza-CMP/AuxPdy is attributed to the unique photothermal effect induced by aza-CMP, which can promote the catalytic benzyl alcohol oxidation occurring at AuPd. This work presents a novel approach to effectively utilize solar energy for conventional catalytic reactions through photothermal effect.
Catalytic PtPd bimetal nanocrystals with high-index facets for radiation injury repair
Long Wei , Wang Jingya , Xu Fujuan , Wu Hongying , Mu Xiaoyu , Wang Junying , Sun Yuanming , Zhang Xiao-Dong
2020, 31(1): 269-274  doi: 10.1016/j.cclet.2019.03.044
[Abstract](64) [FullText HTML] [PDF 1037KB](1)
Radiotherapy is one of the most important clinical cancer treatments, which works mainly by delivering a prescribed radiation dose to the tumor tissues. However, high doses of radiation may also lead many irreversible damages to the surrounding normal tissues. Thereby, how to effectively reduce these sideeffects has been a significant factor in influencing cancer therapeutic effect. In this work, we synthesized the hollow PtPd nanocubes with high-index facets, and investigated the radiation protection capability in vitro and in vivo. Our results showed the PtPd nanocrystals can decrease the ROS level and improve the survival rate of radiated cells. Meanwhile, survival rate of radiated mice can significantly increase from 0 to 30% after PtPd treatment. Consequently, the enzyme and ROS level in radiated mice can be recovered.
A reactive oxygen species-responsive dendrimer with low cytotoxicity for efficient and targeted gene delivery
Wang Yueqi , Li Changjian , Du Libo , Liu Yang
2020, 31(1): 275-280  doi: 10.1016/j.cclet.2019.03.040
[Abstract](52) [FullText HTML] [PDF 1008KB](2)
Nonviral vectors have been attracting more attention for several advantages in gene delivery and the development of nonviral gene carriers with high delivery efficiency and low cytotoxicity has long been a key project. Starburst polyamidoamine dendrimers are a class of synthetic polymers with unique structural and physical characteristics. However, when they are used as gene carrier, the gene transfection efficiency is not satisfactory. Herein, a novel thioketal-core polyamidoamine dendrimer (i.e., ROS-PAMAM) was synthesized and characterized. Compared to ethylenediamine-core dendrimers or widely used cationic polymers of polyetherimide, ROS-PAMAM showed lower cytotoxicity. Moreover, ROS-PAMAM demonstrated reactive oxygen species responsive characteristics, which can facilitate the release of siRNA in the tumor microenvironment. In vitro gene transfection experiments based on A549 cells confirmed that siRNA/ROS-PAMAM exhibits high gene transfection efficiency. It is concluded that ROS-PAMAM shows great potential as a generalizable vehicle for gene therapy applications.
CO2/NIR light dual-controlled nanoparticles for dsDNA unzipping
Wang Yanjing , Yuan Hongbo , Li Dawei , Xing Chengfen
2020, 31(1): 281-284  doi: 10.1016/j.cclet.2019.04.020
[Abstract](52) [FullText HTML] [PDF 809KB](2)
Both of carbon dioxide (CO2) and near-infrared (NIR) light as triggers for non-invasive remotely control are attracting wide attentions due to their good biocompatibility and easy operation. Here, CO2/NIR light dual controlled nanoparticles are proposed to remotely regulate the unzipping of dsDNA by using imidazole functionalized conjugated polymer nanoparticles (imidazole-CPNs). The dsDNA successfully coats on the shell of imidazole-CPNs to form imidazole-CPNs/dsDNA assembly due to intensively electrostatic interaction triggered by CO2. Furthermore, the unzipping process of dsDNA is remotely controlled by NIR light based on the photothermal effect, and it can be readily monitored by the fluorescence intensity of ethidium bromide (EB) and CD spectra of dsDNA. Thus, dual stimulation responsive imidazole-CPNs effectively control dsDNA unzipping under CO2 stimulus and NIR light, promising a new direction in the biological applications of DNA, such as the treatments of diseases caused by gene duplication abnormality.
Fabrication of doxorubicin and chlorotoxin-linked Eu-Gd2O3 nanorods with dual-model imaging and targeted therapy of brain tumor
Zhang Weina , Huang Zhongbing , Pu Ximing , Chen Xianchun , Yin Guangfu , Wang Lei , Zhang Fei , Gao Fabao
2020, 31(1): 285-291  doi: 10.1016/j.cclet.2019.04.018
[Abstract](60) [FullText HTML] [PDF 1084KB](1)
It is urgent to find a technology accurately to better diagnose and treat to brain tumor. Eu-doped Gd2O3 nanorods (Eu-Gd2O3 NRs) with paramagnetic and fluorescent properties were conjugated with doxorubicin (Dox) and chlorotoxin (CTX) via PEGylation, hydrazone bond and sulfur bond (named as CTXNRs-Dox), and these NRs could release more Dox in lower pH environment. The results of cell experiments indicated that CTX-NRs-Dox had obvious targeting and toxic effects on U251 cells, as well as good fluorescence imaging behavior. The orthotopic glioma-transplanted mice models were constructed via the intracranial injection of glioma cells (U87MG). The result of experiments after the tail-vein injection of the prepared NRs suggested that CTX-NRs-Dox could target to brain tumors via the long-time blood circulation, leading to their obvious contrast enhancement of MR imaging of the intracranial tumor and their significant inhibitory effect on the growth and metastasis of brain tumors. A mechanism of synergistic effect of CTX-NRs-Dox on targeting and inhabiting the brain tumor was proposed. Our research suggested that CTX-NRs-Dox had potential application prospect in the detection and treatment of glioma.
Preparation and reducing-responsive property of a novel functional polyurethane nanoemulsion
Qin He , Zhang Hong , Zhou Xiaoteng , Gu Danfei , Li Lingxiao , Kan Chengyou
2020, 31(1): 292-294  doi: 10.1016/j.cclet.2019.04.015
[Abstract](52) [FullText HTML] [PDF 843KB](3)
As a kind of stimuli-responsive materials, the disulfide-containing material has received a tremendous amount of interest. A novel functional disulfide-containing waterborne polyurethane (DS-WPU) nanoemulsion was prepared via a one-step in situ phase inverse emulsification technique and its reducing-responsive property was investigated using dithiothreitol as the reductant. Results showed that the DS-WPU nanoemulsion had a uniform particle size in nanoscale and a good film-forming characteristic, and the DS-WPU latex film exhibited great responsiveness along with a self-assembled behavior in the reducing environment to form WPU emulsion again, including a long-to-short process of the polymer chains.
A novel strategy for boosting the photoluminescence quantum efficiency of CdSe nanocrystals at room temperature
Wang Biwei , Liu Limin , Zhang Yi , Deng Yonghui , Dong Angang
2020, 31(1): 295-298  doi: 10.1016/j.cclet.2019.03.043
[Abstract](61) [FullText HTML] [PDF 831KB](2)
Highly luminescent colloidal nanocrystals have wide applications in bioimaging and various optoelectronic devices. Herein we report a facile and mild procedure by combining S2- treatment and binary ligand passivation, which can efficiently enhance the luminescent property of CdSe nanocrystals at room temperature. The photoluminescence quantum yield of as-treated CdSe nanocrystals exhibits drastic enhancement (e.g., 188 times for CdSe nanorods) after this dual-passivation treatment. The methodology proposed here can be applied to various CdSe nanocrystals, regardless of their sizes, shapes, and crystal structures.
Diphenyl cyclopropenone-centered polymers for site-specific CO-releasing and chain dissociation
Shao Chenchen , Duan Hanyi , Min Yuqin , Zhang Xinghong
2020, 31(1): 299-302  doi: 10.1016/j.cclet.2019.03.053
[Abstract](58) [FullText HTML] [PDF 819KB](2)
The synthesis and stimuli-responsiveness of a diphenyl cyclopropenone (DPCP)-centered poly(methyl acrylate) (PMA) are presented. DPCP-centered PMA could release carbon monoxide (CO) upon UV light in a switched on-and-off manner. The CO-releasing process can be reported by the variations in photoluminescence spectra. In addition, DPCP moiety covalently embedded in the crosslinked polyurethane could also release CO under UV light. Of special, DPCP-centered PMA in solution was selectively dissociated at the phenol ester bond under the ultrasound, and a force-induced hydrolyzation reaction was revealed by D2O exchanging 1H NMR spectra. The kinetic study reveals that small quantity of water could enhance the chain scission rate. This work provides a DPCP-centered polymer for sitespecific CO-releasing and chain dissociation.
Hierarchically porous carbon cages synthesized through in situ migration of templates
Fang Qing , Zhang Wei , Chen Xinghua , Zhang Yuanjian , Hu Ming
2020, 31(1): 303-306  doi: 10.1016/j.cclet.2019.04.006
[Abstract](63) [FullText HTML] [PDF 747KB](2)
In order to optimize mass transportation and exchange, nature creates hierarchically porous networks which are composed of multi-level branches. Although bottom-up templating methods have succeeded in fabrication of these kinds of hierarchically porous networks, the templates have to be assembled/ packed in advance, therefore, driving the fabrication process too complex. In this report, we presented that the hierarchically porous networks could be fabricated through migration of templates, which was similar to formation of rivers. During thermal pyrolysis of Prussian blue cages, the in situly generated iron oxides nanoparticles diffused and aggregated together to grow larger, and eventually moved outside from the porous carbons. The moving routes of the iron oxides became hierarchical channels in the obtained carbon cages. By using the porous carbon cages as electrode for Na-ion battery, a pseudocapacitor-type ion storage was investigated.
Direct benzylic functionalization of pyridines: Palladiumcatalyzed mono-α-arylation of α-(2-pyridinyl)acetates with heteroaryl halides
Jin Chaochao , Xu Kun , Fan Xiao , Liu Changyao , Tan Jiajing
2020, 31(1): 91-94  doi: 10.1016/j.cclet.2019.06.028
[Abstract](59) [FullText HTML] [PDF 941KB](3)
Herein, we report a Pd-catalyzed mono-α-arylation reaction for pyridine benzylic functionalization. This approach serves as an efficient alternative to synthesize di-heteroaryl acetates in good yields and selectivities. Moreover, the method is applicable to heteroaryl substrate combinations, and exhibits great functional group tolerance. A streamlined protocol also enables the rapid synthesis of diheteroaryl ketones. The synthetic value was also demonstrated by scale-up experiments
Cavity-directed nitroaromatics sensing within a carbazolebased luminescent supramolecular M2L3 cage
Feng Tianchi , Li Xuezhao , Wu Jinguo , He Cheng , Duan Chunying
2020, 31(1): 95-98  doi: 10.1016/j.cclet.2019.04.059
[Abstract](52) [FullText HTML] [PDF 976KB](3)
The design and preparation of luminescent M2L3 metal-organic cage via the coordination-driven selfassembly of carbazole-based ligand with a V-shaped geometry is described. The cage Zn-L1 with an open cavity which equipped aromatic rich ligands shows the highest emission quenching efficiency towards picric acid than other nitroaromatic explosives. The quenching ability depended on whether there formed the host-guest molecules are well explored by electrospray ionization mass spectrometry (ESIMS), and isothermal titration microcalorimetry (ITC).
Cyclodextrin derivatives functionalized highly sensitive chiral sensor based on organic field-effect transistor
Wu Yifan , Wang Xuepeng , Li Xiaoxuan , Xiao Yin , Wang Yong
2020, 31(1): 99-102  doi: 10.1016/j.cclet.2019.04.074
[Abstract](56) [FullText HTML] [PDF 871KB](2)
Novel highly sensitive chiral organic field-effect transistors (COFET) were developed by directly assembling imidazolium3, 5-dimethylphenylcabamoylated-β-cyclodextrin(Im+-Ph-β-CD)and 3, 5-dimethylphenylcarbamoylated-β-CD (Ph-β-CD) respectively onto the semiconductor layer as sensing units. The Im+-Ph-β-CD/COFET afforded better enantioselectivity and a lowest detection concentration of 10 18 L/mol as well as the potentiality in quantitative analysis of commercial medicines.
Ruthenium catalyzed amination cyclization of 1, 2, 4-butanetriol with primary amines: A borrowing hydrogen strategy for 3-pyrrolidinol synthesis
Xu Qing-Song , Li Chen , Xu Yong , Xu Defeng , Shen Mei-Hua , Xu Hua-Dong
2020, 31(1): 103-106  doi: 10.1016/j.cclet.2019.05.027
[Abstract](57) [FullText HTML] [PDF 787KB](3)
A ruthenium based catalytic system ([Ru(p-cymene)Cl2]2/XantPhos with substoichiometric Cs2CO3) has been established to effectively achieve the first direct amination cyclization of 1, 2, 4-butanetriol with primary aromatic amines. The product of this sustainable hydrogen autotransfer process is valuable Naryl-3-pyrrolidinol.
Total synthesis of TRADD death domain with arginine N-GlcNAcylation by hydrazide-based native chemical ligation
Wu Ye , Li Yulei , Cong Wei , Zou Yan , Li Xiang , Hu Honggang
2020, 31(1): 107-110  doi: 10.1016/j.cclet.2019.05.010
[Abstract](54) [FullText HTML] [PDF 936KB](5)
TNFR1-associated death domain protein (TRADD) with arginine N-GlcNAcylation is a novel and structurally unique posttranslational modification (PTM) glycoprotein that blocks the formation of death-inducing signaling complex (DISC), orchestrating host nuclear factor kB (NF-kB) signaling in entero-pathogenic Escherichia coli (EPEC)-infected cells. This particular glycosylated modification plays an extremely vital role for the effective colonization and pathogenesis of pathogens in the gut. Herein we describe the total synthesis of TRADD death domain (residues 195-312) with arginine235 N-GlcNAcylation (Arg-GlcNAc TRADD (195-312)). Two longish peptidyl fragments of the wild-type primary sequence were obtained by robust, microwave-assisted, highly efficient, solid-phase peptide synthesis (SPPS), the N-GlcNAcylated sector was built by total synthesis and attached specifically to resinbound peptide with an unprotected ornithine residue via silver-promoted on-resin guanidinylation, Arg-GlcNAc TRADD (195-312) was constructed by hydrazide-based native chemical ligation (NCL). The facile synthetic strategy is expected to be generally applicable for the rapid synthesis of other proteins with Arg-GlcNAc modification and to pave the way for the related chemically biological study.
Air-tolerant direct reductive N-methylation of amines using formic acid via simple inorganic base catalysis
Huang Yan , Deng Wei , Lin Bo-Lin
2020, 31(1): 111-114  doi: 10.1016/j.cclet.2019.04.064
[Abstract](58) [FullText HTML] [PDF 805KB](3)
The construction of N-methyl amine moieties is an important reaction that has found numerous applications. Development of new methylation agents that are more environmentally benign than classical agents, such as iodomethane and methyl sulfate, is still highly desirable. Herein, we report a convenient protocol for direct reductive N-methylation of amines using formic acid as the methylation agent via simple inorganic base catalysis. The present protocol operates under transition-metal-free and air-tolerant conditions. Both the catalyst, K2HPO4, and the reductant, polymethylhydrosiloxane (PMHS), are cheap and easily separable from the crude reaction product mixture. Mechanistic investigations suggest that the reaction occur through the formation of an acetal intermediate followed by the C-N bond formation.
Promoting condensation kinetics of polymeric carbon nitride for enhanced photocatalytic activities
Ni Dongya , Zhang Yuye , Shen Yanfei , Liu Songqin , Zhang Yuanjian
2020, 31(1): 115-118  doi: 10.1016/j.cclet.2019.04.068
[Abstract](60) [FullText HTML] [PDF 819KB](3)
Polymeric carbon nitride (CN) semiconductor by thermal condensation of N-rich precursors has attracted much attention for its capability ranging from photocatalytic and photoelectrochemical energy conversion to biosensing. However, the influence of condensation process on the final structure of CN was rarely studied, making the condensation kinetic far from be fully optimized. Herein, we report the preparation of CN by a simple condensation kinetics modulation using a faster ramping rate during the polymerization process. The modified condensation recipe was even simpler than the conventional one, but led to an improved photocatalytic H2 evolution up to 3 times without any additional chemicals or other complements. Detailed mechanism studies revealed the increase of crystallinity and surface area due to the rapid condensation played the key roles. This work would offer a more facile and effective way to prepare bulk CN for large-scale industrial applications of bulk CN with higher photocatalytic actives for sustainable energy, environmental and biosensing.
Synthesis of two A-B-C type conjugated amphiphilic triblock fullerene derivatives and their application in organic solar cells
Liu Jikang , Jiang Pengfei , Wang Yao , Tu Guoli
2020, 31(1): 119-124  doi: 10.1016/j.cclet.2019.05.023
[Abstract](65) [FullText HTML] [PDF 984KB](2)
Two A-B-C type conjugated amphiphilic triblock fullerene derivatives C60-2HMTPB and C60-2EHTPB were obtained in multi steps synthesis with three different blocks, and the amphiphilic diblock molecular C60-4TPB was also preferred as a reference. When as modifying layer on zinc oxide (ZnO), the three fullerene derivatives can all reduce the work function of ZnO via modulation of the interfacial dipoles and lead a better electrical coupling. As introducing treatment of toluene, the obvious self-assembly of fullerene derivatives were observed, which were supported by X-ray diffraction and contact angle of water measurement. Base on PTB7-Th:PC71BM system, the inverted organic solar cells devices with structure of ITO/ZnO/fullerene derivatives/PTB7-Th:PC71BM/MoO3/Al got power conversion efficiencies of 8.62%, 8.83% and 9.00% for C60-4TPB, C60-2HMTPB and C60-2EHTPB, respectively, compared 8.13% of devices with bare ZnO. The result of conjugated amphiphilic triblock fullerene derivatives provides a straightforward approaching by simultaneously modulating the morphology and interfacial work function of ZnO, which can also lead high performance in optoelectronic devices.
A ratiometric fluorescent probe for alkaline phosphatase with high sensitivity
Yang Yangyang , Zhang Chen , Pan Rizhao , Zhang Shiwei , Yao Shengtao , Tang Yao , Zhu Weilong , Wang Liyue , Zhu Weiping , Xu Yufang , Qian Xuhong
2020, 31(1): 125-128  doi: 10.1016/j.cclet.2019.04.037
[Abstract](59) [FullText HTML] [PDF 850KB](5)
Alkaline phosphatase (ALP) is one of essential biomarkers in mammalian tissue. Here we report a ratiometric probe for ALP, which is rationally designed and synthesized by employing ESIPT fluorophore N-(3-(benzo[d]thiazol-2-yl)-4-hydroxyphenyl)benzamide (BTHPB). The enzymatic dephosphorylation converts the probe to BTHPB, which exhibits a large spectral red-shift (120 nm), allowing extremely high sensitivity of ALP sensing at 0.004 mU/mL. The probe also shows excellent biocompatibility and has been applied for monitoring the endogenic ALP in living cells.
Direct conversion of methane to methanol over Cu exchanged mordenite: Effect of counter ions
Ma Chuang , Tan Xianjun , Zhang Haijiao , Shen Qun , Sun Nannan , Wei Wei
2020, 31(1): 235-238  doi: 10.1016/j.cclet.2019.03.039
[Abstract](54) [FullText HTML] [PDF 981KB](2)
Direct conversion of methane (CH4) to methanol (DMTM) is a promising, but very challenging process for the utilization of abundant CH4 as a low carbon resource. In this context, Cu loaded zeolites, mordenite (MOR) in particular, were recognized as the most effective system to perform DMTM. In this work, different Cu salts were used to exchange with MOR, by which the effect of counter ions on the catalytic performance towards DMTM was investigated. The prepared catalysts were characterized and evaluated systematically. It was found that the counter ions affected the speciation of Cu sites, probably due to their capability in extraction of protons from MOR and the influence on the hydrolysis state of the Cu2+ in aqueous solution. These behaviors adjusted the association between Cu2+ and the exchangeable protons in MOR. As a result, varied DMTM performance was observed. Among the used Cu salts, Cu(CH3COO)2 exchanged MOR showed the highest performance, achieving stable CH3OH yield of 117±28 μmol/g in 5 consecutive cycles, these values are among the highest for Cu loaded MOR zeolites in open publications.
Graphene-supported biomimetic catalysts with synergistic effect of adsorption and degradation for efficient dye capture and removal
Li Qin , Wang Xiaopei , Xiong Xueqing , Zhu Shuihong , Meng Zhaohui , Hong Yongying , Lin Changxu , Liu Xiangyang , Lin Youhui
2020, 31(1): 239-243  doi: 10.1016/j.cclet.2019.04.039
[Abstract](64) [FullText HTML] [PDF 891KB](2)
Design and development of iron porphyrin-based artificial enzymes system have been attracting a lot of attention. Herein, without any toxic reductant and harsh processing, we present a facile one-pot method to fabricate bifunctional catalytic nanocomposites consisting of graphene and hemin by using vitamin C as a mild reduction reagent. The presence of graphene helps the formation of a high degree of highly active and stable hemin on the graphene surface in a monomeric form through their π-π stacking interaction. As a result, such nanocomposites possess a superior adsorption capacity and intrinsic peroxidase-like catalytic activity. Moreover, by the combination of their dye adsorption ability, RGOhemin nanocomposites can serve as a suitable candidate for efficient capture and removal of dyes via a synergistic effect. Our findings may pave the way to apply graphene-supported artificial enzymes in a variety of fields, such as environmental chemistry, bionics, medicine, and biotechnology
Surfactant-assisted fabrication of graphene frameworks endowing epoxy composites with superior thermal conductivity
Zhang Fan , Ye Chen , Dai Wen , Lv Le , Yuan Qilong , Chee KuanW.A. , Yang Ke , Jiang Nan , Lin Cheng-Te , Zhan Zhaolin , Dai Dan , Li He
2020, 31(1): 244-248  doi: 10.1016/j.cclet.2019.04.001
[Abstract](65) [FullText HTML] [PDF 990KB](2)
With the rapid growth in electronic device performance, there has been an increasing demand for thermally conductive polymer composites to handle the thermal management issue, thus contributing to the great importance to develop the graphene framework, which is evaluated as the most promising reinforcements for enhancing the thermal conductivity of polymer. Vacuum filtration is a common method to fabricate graphene framework, whereas, it is available to prepare a framework with centimeter-scale thickness by filtrating the graphene-water dispersion, due to the fact of sample cracking caused by the mismatch of surface tension between graphene and water. In this work, a surfactantassisted strategy was proposed by adjusting the surface tension of the water close to that of graphene first, then performing a conventional filtration process, to fabricate graphene framework. As a result, a thick graphene framework (thickness: 3 cm) was successfully prepared, and after embedding into epoxy, the framework endows the composite (13.6 wt%) with a high in-plane thermal conductivities of 12.4 W/mK, which is equivalent to ≈64 times higher than that of neat epoxy. Our method is simple and compatible with the conventional filtration process, suggesting great potential for the mass-production of graphene framework to meet the practical application requirements.
A general strategy for one-step fabrication of biocompatible microcapsules with controlled active release
Sun Zeyong , Yang Chenjing , Eggersdorfer Max , Cui Jiecheng , Li Yiwei , Hai Mingtan , Chen Dong , Weitz DavidA.
2020, 31(1): 249-252  doi: 10.1016/j.cclet.2019.04.040
[Abstract](65) [FullText HTML] [PDF 925KB](2)
Fabrication of biocompatible core-shell microcapsules in a controllable and scalable manner remains an important but challenging task. Here, we develop a one-step microfluidic approach for the highthroughput production of biocompatible microcapsules, which utilizes single emulsions as templates and controls the precipitation of biocompatible polymer at the water/oil interface. The facile method enables the loading of various oils in the core and the enhancement of polymer shell strength by polyelectrolyte coating. The resulting microcapsules have the advantages of controllability, scalability, biocompatibility, high encapsulation efficiency and high loading capacity. The core-shell microcapsules are ideal delivery vehicles for programmable active release and various controlled release mechanisms are demonstrated, including burst release by vigorous shaking, pH-triggered release for targeted intestinal release and sustained release of perfume over a long period of time. The utility of our technique paves the way for practical applications of core-shell microcapsules.
Magnetic responsive polymer nanofiber composites for easy collecting chemical spills
Meng Hongyu , Wan Jiping , Jing Jingyun , Sun Dayin , Jiang Bingyin , Liang Fuxin , Yang Zhenzhong
2020, 31(1): 253-255  doi: 10.1016/j.cclet.2019.04.002
[Abstract](57) [FullText HTML] [PDF 812KB](2)
We describe a simple method to prepare magnetic responsive polydivinylbenzene (PDVB) nanofiber composites by precipitated cationic living polymerization in the present of oleic acid capped Fe3O4 nanoparticles (NPs). The Fe3O4 NPs are encapsulated with the PDVB forming dendrites, from which thin nanofibers are grown in the tip-growth mode. The thin nanofibers are interwoven with the thick nanofibers forming robust composite network. The composites are magnetic responsive and highly efficient to gel almost all chemicals. Separation of the gelled chemicals from water becomes easier with a magnet. The performance is promising for magnetic collection of chemical spills.
High-refractive index acrylate polymers for applications in nanoimprint lithography
Tang Yunhui , Cabrini Stefano , Nie Jun , Pina-Hernandez Carlos
2020, 31(1): 256-260  doi: 10.1016/j.cclet.2019.04.012
[Abstract](55) [FullText HTML] [PDF 922KB](3)
The development of polymeric optical materials with a higher refractive index, transparency in the visible spectrum region and easier processability is increasingly desirable for advanced optical applications such as microlenses, image sensors, and organic light-emitting diodes. Most acrylates have a low refractive index (around 1.50) which does not meet the high performance requirements of advanced optical materials. In this research, three novel acrylates were synthesized via a facile one-step approach and used to fabricate optical transparent polymers. All of the polymers reveal good optical properties including high transparency (≥90%) in the visible spectrum region and high refractive index values (1.6363) at 550 nm. Moreover, nanostructures of these acrylate polymers with various feature sizes including nanogratings and photonic crystals were successfully fabricated using nanoimprint lithography. These results indicate that these acrylates can be used in a wide range of optical and optoelectronic devices where nanopatterned films with high refractive index and transparency are required.
Carbon dioxide-controlled assembly based on conjugated polymer and boron nitride
Wang Bo , Xing Chengfen , Gao Dong , Yuan Hongbo , Qiu Liang , Yang Xue , Huang Yang , Zhan Yong
2020, 31(1): 261-264  doi: 10.1016/j.cclet.2019.03.037
[Abstract](49) [FullText HTML] [PDF 844KB](2)
CO2-controlled assembly of conjugated polymer and boron nitride (BN) was fabricated via electrostatic and hydrophobic interactions between the BN fiber and conjugated polymer of PFBT containing fluorene units and 2, 1, 3-benzothiadiazole units. CO2, an effective and green stimulus for regulating the assembly of PFBT and BN fibers, leads to an obvious fluorescence variation. Moreover, PFBT enables the assembly with the signal amplification and light-harvesting properties. This work provides a new triggering method to construct intelligent conjugated polymer-based platform, and offers fluorescence monitoring strategy for carbon dioxide capture.
Processing micrometer-sized particles in crumpled graphene network for freestanding membrane enabled by freeze casting
Cao Jing , Zhao Xiaoli , Wang Jiahe , Dou Huanglin , Liu Congcong , Yan Xiaojun , Yan Yuantao , Guo Min , Zhao Wanyu , Yang Xiaowei
2020, 31(1): 265-268  doi: 10.1016/j.cclet.2019.03.041
[Abstract](52) [FullText HTML] [PDF 1187KB](2)
Graphene oxide (GO) is widely used in the construction and application of various 2D membrane-based materials due to its unique colloidal structure. Herein, we demonstrate that micrometer-sized particles can make up freestanding membranes enabled by the extraordinary amphiphilic and polymer-like properties of graphene oxide through freeze casting. The 2D macromolecule, GO could well wrap the particles for better uniformity and stability in either dispersion or membrane. Importantly, freeze casting plays an important role in avoiding the severe aggregation of micrometer-sized particles in the solventremoving process. After reduction, the membrane exhibits good electrical conductivity while maintaining its integral structure, which can be directly used as a freestanding binder-free electrode. This work provides a universal approach to fabricate freestanding membranes with various micrometersized materials for energy storage.
Sensitive and selective molecularly imprinted electrochemical sensor based on multi-walled carbon nanotubes for doxycycline hyclate determination
Xu Zeyu , Jiang Xingxing , Liu Shuping , Yang Minghui
2020, 31(1): 185-188  doi: 10.1016/j.cclet.2019.04.026
[Abstract](53) [FullText HTML] [PDF 731KB](3)
An electrochemical sensor for doxycycline hyclate (DC) detection with high sensitivity and good selectivity is reported. The sensor was fabricated by electro-polymerization of molecularly imprinted polymers (MIPs) in the presence of DC onto multi-walled carbon nanotubes modified glassy carbon electrode (MWCNTs/GCE). The MWCNTs can significantly increase the current response of the sensor, leading to enhanced sensitivity. The MIPs provide selective recognition sites for DC detection. The experimental parameters, such as the polymer monomer concentration, supporting electrolyte pH, the time for electro-polymerization and the incubation time of the sensor with DC were optimized. Under optimized experimental conditions, the sensor displayed a linear range of 0.05 μmol/L-0.5 μmol/L towards DC detection, with the detection limit of 1.3×10-2 μmol/L. The sensor was successfully applied for recovery test of DC in human serum samples.
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