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2017 Volume 34 Issue 7
2017, 34(7): 733-743
doi: 10.11944/j.issn.1000-0518.2017.07.170035
Abstract:
Recently, the smart glucose-sensitive self-regulated drug delivery systems have attracted extensive attention. These smart drug delivery platforms can mimic the physiological model of pancreatic insulin secretion with a timely precise drug dose to control the blood glucose level effectively, and has broad application prospects in the treatment of diabetes. Phenylboronic acid(PBA)-functionalized glucose-sensitive polymer nanocarriers have been studied widely and have great stability, long term storability, and reversible glucose-sensitivity. According to response factors, there are pH-, temperature-, and light-responsive nanocarriers for glucose-sensitive drug delivery. This review covers the development, properties, and applications of glucose sensitive nanocarriers based on PBA, and the prospects are predicted.
Recently, the smart glucose-sensitive self-regulated drug delivery systems have attracted extensive attention. These smart drug delivery platforms can mimic the physiological model of pancreatic insulin secretion with a timely precise drug dose to control the blood glucose level effectively, and has broad application prospects in the treatment of diabetes. Phenylboronic acid(PBA)-functionalized glucose-sensitive polymer nanocarriers have been studied widely and have great stability, long term storability, and reversible glucose-sensitivity. According to response factors, there are pH-, temperature-, and light-responsive nanocarriers for glucose-sensitive drug delivery. This review covers the development, properties, and applications of glucose sensitive nanocarriers based on PBA, and the prospects are predicted.
2017, 34(7): 744-748
doi: 10.11944/j.issn.1000-0518.2017.07.160418
Abstract:
Poly(propylene carbonate)(PPC) is a new thermoplastic biodegradable material. However, its poor thermal and mechanical properties prevent its application in many fields. In corporation the straw flour, a by-product of agricultural products, into PPC is expected to enhance the mechanical properties of PPC and at the same time to find a way to make comprehensive use of straw resources. Chlorided poly(propylene carbonate)(CPPC), which was prepared by chlorination of PPC, possesses good wetting and adhering abilities on the surface of nature fibers. In this study, the PPC/straw flour composites compatibilized with CPPC were prepared by melt blending. The composites are characterized by scanning electron microscopy(SEM), tensile test, dynamic mechanical analysis(DMA) and rotational rheometer, focusing on the effect of CPPC contents on the mechanical and rheological properties of the composites. The results indicate that the tensile strength is increased by 38% for the 70/30 mass ratio of PPC to straw flour composites when 1.8%(mass fraction) CPPC is added. Moreover, the viscosity of the composite decreases with the introduction of CPPC and the processing property is improved accordingly. As a consequence, CPPC as compatibilizer provides a new way to prepare high performance PPC/natural fiber composites.
Poly(propylene carbonate)(PPC) is a new thermoplastic biodegradable material. However, its poor thermal and mechanical properties prevent its application in many fields. In corporation the straw flour, a by-product of agricultural products, into PPC is expected to enhance the mechanical properties of PPC and at the same time to find a way to make comprehensive use of straw resources. Chlorided poly(propylene carbonate)(CPPC), which was prepared by chlorination of PPC, possesses good wetting and adhering abilities on the surface of nature fibers. In this study, the PPC/straw flour composites compatibilized with CPPC were prepared by melt blending. The composites are characterized by scanning electron microscopy(SEM), tensile test, dynamic mechanical analysis(DMA) and rotational rheometer, focusing on the effect of CPPC contents on the mechanical and rheological properties of the composites. The results indicate that the tensile strength is increased by 38% for the 70/30 mass ratio of PPC to straw flour composites when 1.8%(mass fraction) CPPC is added. Moreover, the viscosity of the composite decreases with the introduction of CPPC and the processing property is improved accordingly. As a consequence, CPPC as compatibilizer provides a new way to prepare high performance PPC/natural fiber composites.
2017, 34(7): 749-756
doi: 10.11944/j.issn.1000-0518.2017.07.160443
Abstract:
As the ligand and biological acceptable parts, polyhexamethylene biguanide hydrochloride(PHMB) are used for stabilizing Ag3+. A series of micron-sized quadricovalent cationic Ag(Ⅲ)-PHMB complexes was synthesized via oxidation of the monovalent silver, followed by stabilization of the oxidized high valence silver ions through complexation with PHMB. From the experimental result of agar well-diffusion method, it can be concluded that the antibacterial activity of Ag(Ⅲ)-PHMB complex is enhanced with increasing viscosity-average relative molecular mass of PHMB and weakened with the increase of the size of Ag(Ⅲ)-PHMB complex. The experimental results reveal that the complex yields the maximum antibacterial activity when the viscosity-average relative molecular mass of ligand is 5428. Though broth dilution method, micron-sized Ag(Ⅲ)-PHMB complex displays excellent antibacterial performance in low mass concentration towards Gram-positive and Gram-negative prokaryotes for excellent antibacterial activity of Ag3+. Compared with AgO, AgNO3 and PHMB, Ag(Ⅲ)-PHMB complex has lower minimal inhibitory concentration(MIC). With the increase of mass concentration, however, because of the reduction of the growth ratio of contacting area between Ag(Ⅲ)-PHMB complex and bacteria and the release radio of antimicrobial active substance, antibacterial activity of micron-sized Ag(Ⅲ)-PHMB complex shows slowly increasing rate.
As the ligand and biological acceptable parts, polyhexamethylene biguanide hydrochloride(PHMB) are used for stabilizing Ag3+. A series of micron-sized quadricovalent cationic Ag(Ⅲ)-PHMB complexes was synthesized via oxidation of the monovalent silver, followed by stabilization of the oxidized high valence silver ions through complexation with PHMB. From the experimental result of agar well-diffusion method, it can be concluded that the antibacterial activity of Ag(Ⅲ)-PHMB complex is enhanced with increasing viscosity-average relative molecular mass of PHMB and weakened with the increase of the size of Ag(Ⅲ)-PHMB complex. The experimental results reveal that the complex yields the maximum antibacterial activity when the viscosity-average relative molecular mass of ligand is 5428. Though broth dilution method, micron-sized Ag(Ⅲ)-PHMB complex displays excellent antibacterial performance in low mass concentration towards Gram-positive and Gram-negative prokaryotes for excellent antibacterial activity of Ag3+. Compared with AgO, AgNO3 and PHMB, Ag(Ⅲ)-PHMB complex has lower minimal inhibitory concentration(MIC). With the increase of mass concentration, however, because of the reduction of the growth ratio of contacting area between Ag(Ⅲ)-PHMB complex and bacteria and the release radio of antimicrobial active substance, antibacterial activity of micron-sized Ag(Ⅲ)-PHMB complex shows slowly increasing rate.
2017, 34(7): 757-767
doi: 10.11944/j.issn.1000-0518.2017.07.160419
Abstract:
2-Oxazoline derivative belongs to an important class of heterocyclic compounds, new synthetic method and new 2-oxazoline derivatives are eagerly desired. In order to develop a new protocol for the synthesis of deferent structural 2-oxazoline derivatives, a method from ethyl α-cyanocinnamate derivatives and N-bromobenzamide has been explored. The structures of all eleven synthesized products were confirmed by proton nuclear magnetic resonance spectroscopy(1H NMR), and mass spectrometry(MS). The results show that a series of ethyl α-cyanocinnamate derivatives(3a~3k) can be smoothly converted into corresponding 2-oxazoline derivatives(5a~5k). When Na2CO3 was used as the promoter in acetone at room temperature, the corresponding products were obtained in high yield(up to 90%). Not only can ethyl α-cyanocinnamate derivatives be used as substrate, but also ethyl α-carbethoxy-cyanocinnamate(6) can be employed as the substrate, too. Experiment results indicate that N-bromo-p-nitrobenzamide(8) and N-bromoacetamide(9) can tolerate this reaction except N-bromobenzamide(4). Above results indicate that the easy and efficient protocol has application in a large scope of electron-deficient olefins and N-bromoamide. A possible mechanism was proposed which can explain well the full regiospecificity of the reaction.
2-Oxazoline derivative belongs to an important class of heterocyclic compounds, new synthetic method and new 2-oxazoline derivatives are eagerly desired. In order to develop a new protocol for the synthesis of deferent structural 2-oxazoline derivatives, a method from ethyl α-cyanocinnamate derivatives and N-bromobenzamide has been explored. The structures of all eleven synthesized products were confirmed by proton nuclear magnetic resonance spectroscopy(1H NMR), and mass spectrometry(MS). The results show that a series of ethyl α-cyanocinnamate derivatives(3a~3k) can be smoothly converted into corresponding 2-oxazoline derivatives(5a~5k). When Na2CO3 was used as the promoter in acetone at room temperature, the corresponding products were obtained in high yield(up to 90%). Not only can ethyl α-cyanocinnamate derivatives be used as substrate, but also ethyl α-carbethoxy-cyanocinnamate(6) can be employed as the substrate, too. Experiment results indicate that N-bromo-p-nitrobenzamide(8) and N-bromoacetamide(9) can tolerate this reaction except N-bromobenzamide(4). Above results indicate that the easy and efficient protocol has application in a large scope of electron-deficient olefins and N-bromoamide. A possible mechanism was proposed which can explain well the full regiospecificity of the reaction.
2017, 34(7): 768-773
doi: 10.11944/j.issn.1000-0518.2017.07.160389
Abstract:
Amoxicillin is a β-lactam antibiotic used for the treatment of a number of bacterial infections. It is on the World Health Organization's List of Essential Medicines, and one of the most important medications needed in a basic health system. The insufficient sources of its impurity L, i.e., (2S, 5R, 6R)-6-((2S, 5R, 6R)-6-((R)-2-amino-2-(4-hydroxyphenyl)acetamido)-3, 3-dime-thyl-7-oxo-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxamido)-3, 3-dimethyl-7-oxo-4-thia-1-azabicy-clo[3.2.0]heptane-2-carboxylic acid(6-APA amoxicilin amide), affect the quality control of the product. Herein, the first synthesis of amoxicillin impurity L, was reported by using a simple and efficient method. The starting materials of 6-aminopenicilanic acid and amoxycillin trihydrate were converted to intermediate compounds 3 and 6 through three-step and one-step reactions, respectively. By using benzotriazole-1-yl-oxytripyrrolidinophosphonium hexafluorophosphate(PyBOP) as peptide coupling reagent, we successfully synthesized key intermediate 7 from compounds 3 and 6 in 76% yield, which was subsequently transformed to 6-APA amoxicillin amide by fully deprotection of benzyl and two carbobenzyloxy(Cbz) protecting groups. This method not only increases the source of the standard substance for quality control of amoxicillin, but also provides inspiration for novel β-lactam antibiotic and antiallergic research.
Amoxicillin is a β-lactam antibiotic used for the treatment of a number of bacterial infections. It is on the World Health Organization's List of Essential Medicines, and one of the most important medications needed in a basic health system. The insufficient sources of its impurity L, i.e., (2S, 5R, 6R)-6-((2S, 5R, 6R)-6-((R)-2-amino-2-(4-hydroxyphenyl)acetamido)-3, 3-dime-thyl-7-oxo-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxamido)-3, 3-dimethyl-7-oxo-4-thia-1-azabicy-clo[3.2.0]heptane-2-carboxylic acid(6-APA amoxicilin amide), affect the quality control of the product. Herein, the first synthesis of amoxicillin impurity L, was reported by using a simple and efficient method. The starting materials of 6-aminopenicilanic acid and amoxycillin trihydrate were converted to intermediate compounds 3 and 6 through three-step and one-step reactions, respectively. By using benzotriazole-1-yl-oxytripyrrolidinophosphonium hexafluorophosphate(PyBOP) as peptide coupling reagent, we successfully synthesized key intermediate 7 from compounds 3 and 6 in 76% yield, which was subsequently transformed to 6-APA amoxicillin amide by fully deprotection of benzyl and two carbobenzyloxy(Cbz) protecting groups. This method not only increases the source of the standard substance for quality control of amoxicillin, but also provides inspiration for novel β-lactam antibiotic and antiallergic research.
2017, 34(7): 774-782
doi: 10.11944/j.issn.1000-0518.2017.07.160427
Abstract:
In order to develop thiourea derivatives with antibacterial activities, a series of novel 1-aryl-3-(3-((2-oxo-2H-chromen-4-yl)oxy)phenyl)thiourea derivative was synthesized from 4-hydroxycoumarin via chlorination, etherification, isothiocyanate formation and addition reactions. The structures of the title compounds were characterized by infrared spectroscopy(IR), nuclear magnetic resonance spectrocopy(NMR) and mass spectrometry(MS). The results show that title compounds exhibit excellent antibacterial activities against Xanthomonas oryzae pv. oryzae(Xoo) and Xanthomonas citri subsp. Citri(Xcc). Among of them, compounds 4k, 4l, 4m and 4n show excellent antibacterial activities against Xoo, with the EC50 values 137.42, 131.05, 129.23 and 117.43 mg/L, respectively, which were better than that of the control agent thiodiazole-copper(195.24 mg/L). Compounds 4k, 4l, 4m and 4n display considerable antibacterial activities against Xcc, with the EC50 values of 97.02, 94.31, 102.28 and 90.52 mg/L, respectively, which are better than that of thiodiazole-copper(120.25 mg/L).
In order to develop thiourea derivatives with antibacterial activities, a series of novel 1-aryl-3-(3-((2-oxo-2H-chromen-4-yl)oxy)phenyl)thiourea derivative was synthesized from 4-hydroxycoumarin via chlorination, etherification, isothiocyanate formation and addition reactions. The structures of the title compounds were characterized by infrared spectroscopy(IR), nuclear magnetic resonance spectrocopy(NMR) and mass spectrometry(MS). The results show that title compounds exhibit excellent antibacterial activities against Xanthomonas oryzae pv. oryzae(Xoo) and Xanthomonas citri subsp. Citri(Xcc). Among of them, compounds 4k, 4l, 4m and 4n show excellent antibacterial activities against Xoo, with the EC50 values 137.42, 131.05, 129.23 and 117.43 mg/L, respectively, which were better than that of the control agent thiodiazole-copper(195.24 mg/L). Compounds 4k, 4l, 4m and 4n display considerable antibacterial activities against Xcc, with the EC50 values of 97.02, 94.31, 102.28 and 90.52 mg/L, respectively, which are better than that of thiodiazole-copper(120.25 mg/L).
2017, 34(7): 783-788
doi: 10.11944/j.issn.1000-0518.2017.07.160440
Abstract:
To introduce the imidazole ring to the bromo-methoxyl benzophenone structures and find the target compounds with high protective activity on vacular endothelium cells, eight novel bromo-methoxyl benzophenone imidazole compounds were synthesized using 5-bromo-2-methylbenzoic acid as starting material via following reactions:acylating chlorination, Friedel acylation, bromination, radical substitution with N-bromosuccinimide(NBS) and nucleophilic substitution with substituted imidazoles. The structures of the target compounds were confirmed by proton and carbon nuclear magnetic resonance spectroscopy(1H and 13C NMR) and high resolution mass spectrometry(HRMS). Additionally, the protective effects of the target compounds against H2O2-induced EA.hy 926 cells injury were evaluated by methylthiazolyldiphenyl-tetrazolium bromide(MTT) assay and their structure-activity relationships were also preliminarily discussed. The in vitro results show that target compounds 6a, 6g and 6h exhibit significant cytoprotective activities and their half maximal inhibitory concentration(EC50) values are 1.9, 4.0 and 3.2 μmol/L, respectively, superior to the positive control Quercetin(EC50≈18 μmol/L). These results also suggest the potential application prospect of target compounds in the treatment of cardiovascular diseases.
To introduce the imidazole ring to the bromo-methoxyl benzophenone structures and find the target compounds with high protective activity on vacular endothelium cells, eight novel bromo-methoxyl benzophenone imidazole compounds were synthesized using 5-bromo-2-methylbenzoic acid as starting material via following reactions:acylating chlorination, Friedel acylation, bromination, radical substitution with N-bromosuccinimide(NBS) and nucleophilic substitution with substituted imidazoles. The structures of the target compounds were confirmed by proton and carbon nuclear magnetic resonance spectroscopy(1H and 13C NMR) and high resolution mass spectrometry(HRMS). Additionally, the protective effects of the target compounds against H2O2-induced EA.hy 926 cells injury were evaluated by methylthiazolyldiphenyl-tetrazolium bromide(MTT) assay and their structure-activity relationships were also preliminarily discussed. The in vitro results show that target compounds 6a, 6g and 6h exhibit significant cytoprotective activities and their half maximal inhibitory concentration(EC50) values are 1.9, 4.0 and 3.2 μmol/L, respectively, superior to the positive control Quercetin(EC50≈18 μmol/L). These results also suggest the potential application prospect of target compounds in the treatment of cardiovascular diseases.
2017, 34(7): 789-794
doi: 10.11944/j.issn.1000-0518.2017.07.160514
Abstract:
In order to explore more effective anti-tumor drugs, and improve the anti-tumor activities of tetrandrine, six new bisbenzylisoquinoline derivatives of tetrandrine were designed and synthesized by Suzuki coupling. The structures of these compounds were confirmed by 1H nuclear magnetic resonance(1H NMR), 13C nuclear magnetic resonance(13C NMR), and mass spectrometry(MS). Their inhibitory activities against human lung cancer cells(A549) and murine leukemia cells(P388) were evaluated by CCK-8(cell counting kit-8) method. All these compounds exhibit a certain level of anti-tumor activities, while compounds H1, H4, H6 possess better cytotoxicity profile than tetrandrine against A549 cells.
In order to explore more effective anti-tumor drugs, and improve the anti-tumor activities of tetrandrine, six new bisbenzylisoquinoline derivatives of tetrandrine were designed and synthesized by Suzuki coupling. The structures of these compounds were confirmed by 1H nuclear magnetic resonance(1H NMR), 13C nuclear magnetic resonance(13C NMR), and mass spectrometry(MS). Their inhibitory activities against human lung cancer cells(A549) and murine leukemia cells(P388) were evaluated by CCK-8(cell counting kit-8) method. All these compounds exhibit a certain level of anti-tumor activities, while compounds H1, H4, H6 possess better cytotoxicity profile than tetrandrine against A549 cells.
2017, 34(7): 795-800
doi: 10.11944/j.issn.1000-0518.2017.07.160456
Abstract:
N, N-Isoquinoline dipole derivatives were synthesized via intramolecular cyclization of o-alkynylbenzaldehyde hydrazones in the presence of silver acetate(AgOAc) in dichloromethane(DCM) at room temperature. The chemical structures of these obtained products were characterized by mass spectrometry and nuclear magnetic resonance spectroscopy(NMR). In addition, the effect of catalysts and their loadings, raw material ratios, solvents and temperatures on the yields was investigated. The target compound (3-(((methoxycarbonyl)oxy)methyl)isoquinolin-2-iu-m-2-yl)(tosyl)-amide is obtained in 60% yield and the substrate adaptability can be up to 85% under optimum conditions. This method has advantages of easy operation, mild reaction condition and functional group tolerance. Through the exploration of experimental conditions and substrate applicability, this paper solves the disadvantages and shortcomings of the method of synthesizing isoquinoline dipole compounds in the past, which provides a new experimental method for the preparation of compounds containing such skeletons.
N, N-Isoquinoline dipole derivatives were synthesized via intramolecular cyclization of o-alkynylbenzaldehyde hydrazones in the presence of silver acetate(AgOAc) in dichloromethane(DCM) at room temperature. The chemical structures of these obtained products were characterized by mass spectrometry and nuclear magnetic resonance spectroscopy(NMR). In addition, the effect of catalysts and their loadings, raw material ratios, solvents and temperatures on the yields was investigated. The target compound (3-(((methoxycarbonyl)oxy)methyl)isoquinolin-2-iu-m-2-yl)(tosyl)-amide is obtained in 60% yield and the substrate adaptability can be up to 85% under optimum conditions. This method has advantages of easy operation, mild reaction condition and functional group tolerance. Through the exploration of experimental conditions and substrate applicability, this paper solves the disadvantages and shortcomings of the method of synthesizing isoquinoline dipole compounds in the past, which provides a new experimental method for the preparation of compounds containing such skeletons.
2017, 34(7): 801-809
doi: 10.11944/j.issn.1000-0518.2017.07.160402
Abstract:
The improvement of dispersibility of catalyst is one of the most effective methods to increase its catalytic activity. After the N-heterocyclic carbene(NHC) ligand containing bulky substituent was modified with glycerol through Ullmann reaction, the responding oxygen-containing groups could effectively improve the stability, dispersibility and catalytic efficiency of this catalyst. Then, this NHC ligand was employed to chelate with palladium acetylacetonate to synthesize the responding catalyst. At last, this compound was employed to catalyze the Suzuki-Miyaura coupling reaction. With p-bromoanisole and phenylboronic acid as the model reaction to evaluate the catalytic activity of this palladium complex, this catalyst exhibits high catalytic activity in different conditions. Furthermore, the highest turnover number(TON) value of the catalyst even reaches up to 99000 due to its good dispersibility in various solvents. Moreover, the catalyst shows excellent catalytic performance towards Suzuki-Miyaura reaction when a wide variety of substituents are employed. Compared with tetrakis(triphenylphosphine)-palladium, the catalyst also keeps good catalytic activity and stability in air atmosphere.
The improvement of dispersibility of catalyst is one of the most effective methods to increase its catalytic activity. After the N-heterocyclic carbene(NHC) ligand containing bulky substituent was modified with glycerol through Ullmann reaction, the responding oxygen-containing groups could effectively improve the stability, dispersibility and catalytic efficiency of this catalyst. Then, this NHC ligand was employed to chelate with palladium acetylacetonate to synthesize the responding catalyst. At last, this compound was employed to catalyze the Suzuki-Miyaura coupling reaction. With p-bromoanisole and phenylboronic acid as the model reaction to evaluate the catalytic activity of this palladium complex, this catalyst exhibits high catalytic activity in different conditions. Furthermore, the highest turnover number(TON) value of the catalyst even reaches up to 99000 due to its good dispersibility in various solvents. Moreover, the catalyst shows excellent catalytic performance towards Suzuki-Miyaura reaction when a wide variety of substituents are employed. Compared with tetrakis(triphenylphosphine)-palladium, the catalyst also keeps good catalytic activity and stability in air atmosphere.
2017, 34(7): 810-817
doi: 10.11944/j.issn.1000-0518.2017.07.170100
Abstract:
Two dimensional flaky composites of MoS2/graphite are first prepared via direct all-solid-state ball-milling using commercial molybdenum disulfide(MoS2) and graphite as raw materials. As evidenced from X-ray difraction, scanning electron microscopy and energy dispersive spectrometry, MoS2 and graphite are exfoliated into thin sheets, which entangle uniformly alleviating the agglomeration of MoS2. Thus as-prepared MoS2/graphite composites exhibit significantly improved cycling stability and rate capability. When tested at the current density of 100 mA/g, MoS2/graphite(mass ratio 7:3) composite shows an initial specific discharge capacity of 801 mA·h/g and retains a reversible specific capacity of 694 mA·h/g after 100 cycles, which is much superior to that of bulk MoS2(about 110 mA·h/g remained after 100 cycles). The outstanding electrochemical performance of ball-milled MoS2/graphite composites could be attributed to following reasons:exfoliated graphite sheets not only improve the electrical conductivity of MoS2/graphite composite, but also prevent the agglomeration of MoS2 during the charge/discharge process, which enhances structural stability of the composite electrode. In addition, the technique reported herein also demonstrates a facile and low-cost method for the production of high performance lithium ion battery electrode materials on a large scale.
Two dimensional flaky composites of MoS2/graphite are first prepared via direct all-solid-state ball-milling using commercial molybdenum disulfide(MoS2) and graphite as raw materials. As evidenced from X-ray difraction, scanning electron microscopy and energy dispersive spectrometry, MoS2 and graphite are exfoliated into thin sheets, which entangle uniformly alleviating the agglomeration of MoS2. Thus as-prepared MoS2/graphite composites exhibit significantly improved cycling stability and rate capability. When tested at the current density of 100 mA/g, MoS2/graphite(mass ratio 7:3) composite shows an initial specific discharge capacity of 801 mA·h/g and retains a reversible specific capacity of 694 mA·h/g after 100 cycles, which is much superior to that of bulk MoS2(about 110 mA·h/g remained after 100 cycles). The outstanding electrochemical performance of ball-milled MoS2/graphite composites could be attributed to following reasons:exfoliated graphite sheets not only improve the electrical conductivity of MoS2/graphite composite, but also prevent the agglomeration of MoS2 during the charge/discharge process, which enhances structural stability of the composite electrode. In addition, the technique reported herein also demonstrates a facile and low-cost method for the production of high performance lithium ion battery electrode materials on a large scale.
2017, 34(7): 818-823
doi: 10.11944/j.issn.1000-0518.2017.07.160417
Abstract:
Variation of the methylamine lead iodine(MAPbI3) precursor thin films during aging at room temperature in the air was studied. With the aging time increasing, more MAPbI3 perovskite is generated and after about 220 min it reaches a stable value while some precursors are still left. The influence of such variation on the subsequent MAPbI3 perovskite thin films was also studied. The X-ray diffraction intensity and UV-Vis absorption of methylamine lead iodine precursor films after aging were lower than those of the as prepared films. The comparison of atomic force microscopy(AFM) surface morphology after thermal annealing shows that the crystalline grain size of thin film made from aged precursor thin film is much smaller than that made from the as prepared precursor film, the crystalline grain size of aged film is about 0.2 μm, and that of the as prepared one is 1.1 m. These phenomena are due to the more MAPbI3 are generated during aging, which acts as more crystal nuclei that lead to smaller crystal grains and lower degree of crystallinity. This work provides a new idea and direction to explore the formation mechanism of methylamine lead iodide perovskite, which is the basic research of methylamine lead iodide perovskite thin film properties. The work has a certain guiding role in the practical production and industrial application in photovoltaic field.
Variation of the methylamine lead iodine(MAPbI3) precursor thin films during aging at room temperature in the air was studied. With the aging time increasing, more MAPbI3 perovskite is generated and after about 220 min it reaches a stable value while some precursors are still left. The influence of such variation on the subsequent MAPbI3 perovskite thin films was also studied. The X-ray diffraction intensity and UV-Vis absorption of methylamine lead iodine precursor films after aging were lower than those of the as prepared films. The comparison of atomic force microscopy(AFM) surface morphology after thermal annealing shows that the crystalline grain size of thin film made from aged precursor thin film is much smaller than that made from the as prepared precursor film, the crystalline grain size of aged film is about 0.2 μm, and that of the as prepared one is 1.1 m. These phenomena are due to the more MAPbI3 are generated during aging, which acts as more crystal nuclei that lead to smaller crystal grains and lower degree of crystallinity. This work provides a new idea and direction to explore the formation mechanism of methylamine lead iodide perovskite, which is the basic research of methylamine lead iodide perovskite thin film properties. The work has a certain guiding role in the practical production and industrial application in photovoltaic field.
2017, 34(7): 833-838
doi: 10.11944/j.issn.1000-0518.2017.07.160445
Abstract:
An important application of psudo ternary phase diagrams is to obtain microemulsion for nano material preparation. Therefore, psudo ternary phase diagrams of sodium dodecyl sulfate(SDS)/n-C5H11OH-cyclohexane-water at 45 ℃ and its conductivity were studied. Pseudo ternary phase diagrams agree well with conductivity measurement. Then psudo ternary phase diagrams of SDS/n-C5H11OH-cyclohexane-water, SDS/n-C5H11OH-cyclohexane-Zn(NO3)2, SDS/n-C5H11OH-cyclohexane-NaOH at 45 ℃ and 65 ℃ were measured and compared. The influence of alkali NaOH and salt Zn(NO3)2 on peudo ternary phase diagrams was discussed. The result shows that oil-in-water(O/W) and water-in-oil(W/O) microemulsion areas are smaller after (Zn(NO3)2) or (NaOH) was added into SDS/n-C5H11OH-cyclohexane-water system. The O/W microemulsion areas disappeared in SDS/n-C5H11OH-cyclohexane-NaOH peudo ternary phase diagrams at 45 ℃. There are still 5 areas in psudo ternary phase diagrams and smaller O/W and W/O microemulsion areas after NaOH or Zn(NO3)2 was added in SDS/cyclohexane-water system at 65 ℃. These study results were applied in the preparation nano ZnO particle in microemulsion system. Tansimission electron microscopy and X-ray diffraction studies show that the sample preparaed by the guidance of psudo ternary phase diagrams is nano ZnO particle.
An important application of psudo ternary phase diagrams is to obtain microemulsion for nano material preparation. Therefore, psudo ternary phase diagrams of sodium dodecyl sulfate(SDS)/n-C5H11OH-cyclohexane-water at 45 ℃ and its conductivity were studied. Pseudo ternary phase diagrams agree well with conductivity measurement. Then psudo ternary phase diagrams of SDS/n-C5H11OH-cyclohexane-water, SDS/n-C5H11OH-cyclohexane-Zn(NO3)2, SDS/n-C5H11OH-cyclohexane-NaOH at 45 ℃ and 65 ℃ were measured and compared. The influence of alkali NaOH and salt Zn(NO3)2 on peudo ternary phase diagrams was discussed. The result shows that oil-in-water(O/W) and water-in-oil(W/O) microemulsion areas are smaller after (Zn(NO3)2) or (NaOH) was added into SDS/n-C5H11OH-cyclohexane-water system. The O/W microemulsion areas disappeared in SDS/n-C5H11OH-cyclohexane-NaOH peudo ternary phase diagrams at 45 ℃. There are still 5 areas in psudo ternary phase diagrams and smaller O/W and W/O microemulsion areas after NaOH or Zn(NO3)2 was added in SDS/cyclohexane-water system at 65 ℃. These study results were applied in the preparation nano ZnO particle in microemulsion system. Tansimission electron microscopy and X-ray diffraction studies show that the sample preparaed by the guidance of psudo ternary phase diagrams is nano ZnO particle.
2017, 34(7): 839-846
doi: 10.11944/j.issn.1000-0518.2017.07.160465
Abstract:
For sensitive bioassay of hemoglobin(Hb), we synthesized Hb imprinted polymers(PIPs) on the surface of 3D Au/Cu nanodendrites prepared on Au electrode. The 3D Au/Cu nanodendrites were fabricated by electrodeposition performed by chronoamperometry at -0.9 V(vs.SCE) for 400 s in an aqueous electrolyte containing CuSO4·5H2O(0.1 mol/L) and HAuCl4·4H2O(0.025 mol/L). The PIPs was prepared with acrylamide as functional monomer, N, N'-methylenebisacrylamide and Hb as crosslinking agent and the template, respectively. The electrode modified with PIPs was examined by cyclic voltammetry(CV) and scanning electron microscope(SEM). Assays of Hb by differential pulse voltammetry(DPV) with PIPs modified electrode show broader linear range and lower detection limit for Hb determination compared to those similar sensors based on PIPs. The linear range is 1.0×10-14~1.0×10-1 mg/L with a detection limit at 1.9×10-15 mg/L(S/N=3). These results indicate that the 3D Au/Cu nanodendrites greatly improve electron transfer ability of electrodes, and also improve the detection range of electrodes modified with PIPs.
For sensitive bioassay of hemoglobin(Hb), we synthesized Hb imprinted polymers(PIPs) on the surface of 3D Au/Cu nanodendrites prepared on Au electrode. The 3D Au/Cu nanodendrites were fabricated by electrodeposition performed by chronoamperometry at -0.9 V(vs.SCE) for 400 s in an aqueous electrolyte containing CuSO4·5H2O(0.1 mol/L) and HAuCl4·4H2O(0.025 mol/L). The PIPs was prepared with acrylamide as functional monomer, N, N'-methylenebisacrylamide and Hb as crosslinking agent and the template, respectively. The electrode modified with PIPs was examined by cyclic voltammetry(CV) and scanning electron microscope(SEM). Assays of Hb by differential pulse voltammetry(DPV) with PIPs modified electrode show broader linear range and lower detection limit for Hb determination compared to those similar sensors based on PIPs. The linear range is 1.0×10-14~1.0×10-1 mg/L with a detection limit at 1.9×10-15 mg/L(S/N=3). These results indicate that the 3D Au/Cu nanodendrites greatly improve electron transfer ability of electrodes, and also improve the detection range of electrodes modified with PIPs.
2017, 34(7): 847-854
doi: 10.11944/j.issn.1000-0518.2017.07.160414
Abstract:
To detect ethylenediamine gas produced by the degradation of flavor during food deterioration process, tetraphenylporphyrin iron was synthesized via Alder method and its thin film/K+ exchanged glass waveguide sensor were prepared by spin coating. This sensor exhibits selective and high sensitive response to ethylenediamine. In the volume ratio range of 1×10-10~1×10-4(V/V0), there is a good linear relationship between the volume ratio and output light intensity(R=0.9940). The response time and recovery time are 3 s and 11 s, respectively. The signal to noise ratio(S/N) is 4.8, RSD=0.5%(V/V0=1×10-7). Good linear relationship between the volume ratio and output light intensity(R=0.9985) in parallel experiments also proves the accuracy of this sensor toward ethylenediamine gas detection. This sensor has potential application in the field of food quality examination.
To detect ethylenediamine gas produced by the degradation of flavor during food deterioration process, tetraphenylporphyrin iron was synthesized via Alder method and its thin film/K+ exchanged glass waveguide sensor were prepared by spin coating. This sensor exhibits selective and high sensitive response to ethylenediamine. In the volume ratio range of 1×10-10~1×10-4(V/V0), there is a good linear relationship between the volume ratio and output light intensity(R=0.9940). The response time and recovery time are 3 s and 11 s, respectively. The signal to noise ratio(S/N) is 4.8, RSD=0.5%(V/V0=1×10-7). Good linear relationship between the volume ratio and output light intensity(R=0.9985) in parallel experiments also proves the accuracy of this sensor toward ethylenediamine gas detection. This sensor has potential application in the field of food quality examination.
2017, 34(7): 824-832
doi: 10.11944/j.issn.1000-0518.2017.07.160423
Abstract:
Thermodynamic parameters of eighteen kinds of organic solvents in ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate([BMIM]PF6) were determined by inverse gas chromatography(IGC) from 343.15 to 373.15 K. The molar enthalpy of sorption, mass fraction activity coefficient, Flory-Huggins interaction parameter, partial molar enthalpy of mixing, and activity coefficient at infinite dilution, were calculated to determine the interactions between [BMIM]PF6 and selected solvents at the indicated temperature range. n-Alkanes, cyclohexane, tetrahydrofuran, ether, and carbon tetrachloride were found to be poor solvents for [BMIM]PF6, while benzene, toluene, m-xylene, dichloromethane, acetone, chloroform, ethyl acetate, methyl acetate, ethanol, and carbinol were favorable solvents for this ionic liquid.
Thermodynamic parameters of eighteen kinds of organic solvents in ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate([BMIM]PF6) were determined by inverse gas chromatography(IGC) from 343.15 to 373.15 K. The molar enthalpy of sorption, mass fraction activity coefficient, Flory-Huggins interaction parameter, partial molar enthalpy of mixing, and activity coefficient at infinite dilution, were calculated to determine the interactions between [BMIM]PF6 and selected solvents at the indicated temperature range. n-Alkanes, cyclohexane, tetrahydrofuran, ether, and carbon tetrachloride were found to be poor solvents for [BMIM]PF6, while benzene, toluene, m-xylene, dichloromethane, acetone, chloroform, ethyl acetate, methyl acetate, ethanol, and carbinol were favorable solvents for this ionic liquid.
