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2019 Volume 47 Issue 1
2019, 47(1): 1-12
doi: 10.19756/j.issn.0253-3820.181411
Abstract:
Sonic-spray ionization (SSI) is one of the simplest and most easily implemented ionization techniques. It relies solely on a high-velocity stream of nebulizing gas coaxial to spray capillary for ion formation with no assistance of externally applied ionization energies (e.g., voltage, heating, ultraviolet radiation, laser beams, corona or glow discharges), which are normally required for other ionization techniques. Gaseous ions are produced at room temperature and under atmospheric pressure due to a statistically unbalanced distribution of charges in the tiny droplets by the pneumatic spray. SSI has been originally used as an atmospheric ion source interface for liquid chromatography-mass spectrometry (LC-MS). The results obtained with the SSI interface are similar to those obtained with electrospray ionization (ESI). The SSI can produce both positive and negative charged droplets duo to the ion concentration distribution model. This will be beneficial for high-throughput MS analysis. Ambient ionization has been developed for rapid and direct MS analysis of analytes in untreated samples in their native environment, and opens an exciting perspective on simplification of analysis procedures by creating ions outside the instrument. Based on the principle of SSI, researchers have developed desorption sonic-spray ionization (DeSSI) as a novel ambient ionization method. The high-velocity sonic spray facilitates matrix penetration, therefore providing more homogenous sampling and longer-lasting ion signals. DeSSI is later renamed to easy ambient sonic spray ionization (EASI), forming an acronym that makes a direct correlation to its easiness. After more than 20 years of development, sonic-spray based ionization methods have shown a broad range of applications in an extremely wide array of specialities. Ranging from both qualitative and quantitative analyses to mass spectrometry imaging, the technique has shown unprecedented simplicity, speed, robustness and ease of use. This review elucidates the ionization mechanism of sonic-spray based ionization methods and reviews the wide applications of sonic-spray based ionization in the fields of life sciences, food safety, forensic chemistry, reaction monitoring, etc.
Sonic-spray ionization (SSI) is one of the simplest and most easily implemented ionization techniques. It relies solely on a high-velocity stream of nebulizing gas coaxial to spray capillary for ion formation with no assistance of externally applied ionization energies (e.g., voltage, heating, ultraviolet radiation, laser beams, corona or glow discharges), which are normally required for other ionization techniques. Gaseous ions are produced at room temperature and under atmospheric pressure due to a statistically unbalanced distribution of charges in the tiny droplets by the pneumatic spray. SSI has been originally used as an atmospheric ion source interface for liquid chromatography-mass spectrometry (LC-MS). The results obtained with the SSI interface are similar to those obtained with electrospray ionization (ESI). The SSI can produce both positive and negative charged droplets duo to the ion concentration distribution model. This will be beneficial for high-throughput MS analysis. Ambient ionization has been developed for rapid and direct MS analysis of analytes in untreated samples in their native environment, and opens an exciting perspective on simplification of analysis procedures by creating ions outside the instrument. Based on the principle of SSI, researchers have developed desorption sonic-spray ionization (DeSSI) as a novel ambient ionization method. The high-velocity sonic spray facilitates matrix penetration, therefore providing more homogenous sampling and longer-lasting ion signals. DeSSI is later renamed to easy ambient sonic spray ionization (EASI), forming an acronym that makes a direct correlation to its easiness. After more than 20 years of development, sonic-spray based ionization methods have shown a broad range of applications in an extremely wide array of specialities. Ranging from both qualitative and quantitative analyses to mass spectrometry imaging, the technique has shown unprecedented simplicity, speed, robustness and ease of use. This review elucidates the ionization mechanism of sonic-spray based ionization methods and reviews the wide applications of sonic-spray based ionization in the fields of life sciences, food safety, forensic chemistry, reaction monitoring, etc.
2019, 47(1): 13-22,85
doi: 10.19756/j.issn.0253-3820.181598
Abstract:
Ion funnel is a new-style ion guider which can reduce spatial divergence and energy dispersity of the transmission ions by using RF electric field to confine the ions radially and the DC axial electric field to move the ions toward the exit, and thus it can greatly increase the ion transmission efficiency and improve the sensitivity of the mass spectrometry. Since ion funnel was invented in 1997, it has attracted a close attention of mass spectrometry scientists all over the world. Ion funnel has been widely used in various kinds of mass spectrometry, and built a bridge with high efficiency ion transmission between low vacuum ionization source and high vacuum mass analyzer. In this paper, the principle, technology development and application progress of ion funnel were reviewed, and the future prospects were presented.
Ion funnel is a new-style ion guider which can reduce spatial divergence and energy dispersity of the transmission ions by using RF electric field to confine the ions radially and the DC axial electric field to move the ions toward the exit, and thus it can greatly increase the ion transmission efficiency and improve the sensitivity of the mass spectrometry. Since ion funnel was invented in 1997, it has attracted a close attention of mass spectrometry scientists all over the world. Ion funnel has been widely used in various kinds of mass spectrometry, and built a bridge with high efficiency ion transmission between low vacuum ionization source and high vacuum mass analyzer. In this paper, the principle, technology development and application progress of ion funnel were reviewed, and the future prospects were presented.
2019, 47(1): 23-29
doi: 10.19756/j.issn.0253-3820.181537
Abstract:
A novel system of electrochemistry coupled with mass spectrometry (EC-MS) was developed. An electrospray ion source with a grounded needle design was used as the interface of the EC-MS, which avoided the damage of the electronic components of the potentiostat and significantly simplified instrument configuration. To evaluate the performance of the novel EC-MS system, the electrochemical reduction behavior of oxidized glutathione (GSSG) and the electrochemical oxidation behavior of reduced glutathione (GSH) were investigated. The experimental result showed that this system had high sensitivity, high reaction efficiency and high speed. As a new analytical approach, it has potential in identification of electrochemical reaction products and intermediates, proteomics and drug metabolism.
A novel system of electrochemistry coupled with mass spectrometry (EC-MS) was developed. An electrospray ion source with a grounded needle design was used as the interface of the EC-MS, which avoided the damage of the electronic components of the potentiostat and significantly simplified instrument configuration. To evaluate the performance of the novel EC-MS system, the electrochemical reduction behavior of oxidized glutathione (GSSG) and the electrochemical oxidation behavior of reduced glutathione (GSH) were investigated. The experimental result showed that this system had high sensitivity, high reaction efficiency and high speed. As a new analytical approach, it has potential in identification of electrochemical reaction products and intermediates, proteomics and drug metabolism.
Detection of S-palmitoylated Proteins in Mouse Heart Tissue Based on Different Precipitation Methods
2019, 47(1): 30-37
doi: 10.19756/j.issn.0253-3820.181619
Abstract:
The acyl-biotinyl exchange (ABE) method is a common method for detection of S-palmitoylated proteins by replacing palmitic acid with biotin. In this study, we compared the effects of acetone precipitation and methanol-chloroform precipitation on the detection of S-palmitoylation protein in acyl-biotin exchange method, and analyzed the S-palmitoylated protein in mouse cardiac tissue. First, N-ethylmaleimide (NEM) was used to block the free sulfhydryl on the protein molecules, and then biotinylation reagent (HPDP-Biotin) was used to label the new produced cysteine thiol cleaved by hydroxylamine (HA) in mouse heart tissue. During the ABE reaction, excess unreacted NEM, HA, and HPDP-Biotin were removed by precipitation of the protein. The S-palmitoylated protein in total protein of heart tissue was labeled with ABE reaction based on different precipitation methods, and the S-palmitoylated protein labeled with biotin was enriched by streptavidin agarose beads. The enriched proteins were analyzed by mass spectrometry, and 50 S-palmitoylated proteins were identified. The acetone precipitation assay group identified 23 S-palmitoylated proteins, and the methanol-chloroform precipitation experimental assay group identified 37 S-palmitoylated proteins. 10 proteins were identified in both groups, and 14 newly identified palmitoylated proteins. The result showed that the cross-complementary combination use of different precipitation methods could be helpful for the identification of palmitoylated proteins.
The acyl-biotinyl exchange (ABE) method is a common method for detection of S-palmitoylated proteins by replacing palmitic acid with biotin. In this study, we compared the effects of acetone precipitation and methanol-chloroform precipitation on the detection of S-palmitoylation protein in acyl-biotin exchange method, and analyzed the S-palmitoylated protein in mouse cardiac tissue. First, N-ethylmaleimide (NEM) was used to block the free sulfhydryl on the protein molecules, and then biotinylation reagent (HPDP-Biotin) was used to label the new produced cysteine thiol cleaved by hydroxylamine (HA) in mouse heart tissue. During the ABE reaction, excess unreacted NEM, HA, and HPDP-Biotin were removed by precipitation of the protein. The S-palmitoylated protein in total protein of heart tissue was labeled with ABE reaction based on different precipitation methods, and the S-palmitoylated protein labeled with biotin was enriched by streptavidin agarose beads. The enriched proteins were analyzed by mass spectrometry, and 50 S-palmitoylated proteins were identified. The acetone precipitation assay group identified 23 S-palmitoylated proteins, and the methanol-chloroform precipitation experimental assay group identified 37 S-palmitoylated proteins. 10 proteins were identified in both groups, and 14 newly identified palmitoylated proteins. The result showed that the cross-complementary combination use of different precipitation methods could be helpful for the identification of palmitoylated proteins.
2019, 47(1): 38-48
doi: 10.19756/j.issn.0253-3820.181531
Abstract:
A novel probe L based on Schift base derivative was synthesized and characterized by 1H NMR,13C NMR, HRMS and FT-IR spectroscopy. The interaction of this probe L with Ca2+, Cu2+ and Zn2+ was investigated by UV-Vis and fluorescence spectra systematically. The results showed that L exhibited high selectivity and sensitivity toward Ca2+, Cu2+ and Zn2+ ions over a wide range of metal ions and anions in ethanol and Tris-HCl (pH 7.4, 9:1, V/V) buffer solution. Meanwhile, L responded these three analytes with unique absorbance enhancement at 335 nm for Cu2+ and distinct fluorescent turned on signal changes at 512 nm and 486 for Ca2+ and Zn2+, respectively. The detection limits of L for Ca2+, Cu2+ and Zn2+ ions were 9.00×10-7 mol/L, 9.23×10-7 mol/L and 5.14×10-7 mol/L, respectively. In additional, L was also successfully used to detect Ca2+, Cu2+ and Zn2+ in the samples (drug, water and serum samples) with satisfactory results. Notably, the L was successfully applied to imaging of Ca2+ and Zn2+ in HepG2 cells, zebra fish and living mice, which indicated that L had great potential in detection of Ca2+ and Zn2+ in vitro and in vivo.
A novel probe L based on Schift base derivative was synthesized and characterized by 1H NMR,13C NMR, HRMS and FT-IR spectroscopy. The interaction of this probe L with Ca2+, Cu2+ and Zn2+ was investigated by UV-Vis and fluorescence spectra systematically. The results showed that L exhibited high selectivity and sensitivity toward Ca2+, Cu2+ and Zn2+ ions over a wide range of metal ions and anions in ethanol and Tris-HCl (pH 7.4, 9:1, V/V) buffer solution. Meanwhile, L responded these three analytes with unique absorbance enhancement at 335 nm for Cu2+ and distinct fluorescent turned on signal changes at 512 nm and 486 for Ca2+ and Zn2+, respectively. The detection limits of L for Ca2+, Cu2+ and Zn2+ ions were 9.00×10-7 mol/L, 9.23×10-7 mol/L and 5.14×10-7 mol/L, respectively. In additional, L was also successfully used to detect Ca2+, Cu2+ and Zn2+ in the samples (drug, water and serum samples) with satisfactory results. Notably, the L was successfully applied to imaging of Ca2+ and Zn2+ in HepG2 cells, zebra fish and living mice, which indicated that L had great potential in detection of Ca2+ and Zn2+ in vitro and in vivo.
2019, 47(1): 49-58
doi: 10.19756/j.issn.0253-3820.181149
Abstract:
Metabolomics based on 1H nuclear magnetic resonance (NMR) was established to explore the protection mechanism of ginsenoside Rb1 on injury of SH-SY5Y cell induced by glutamic acid (Glu). Cell viability was evaluated by methyl thiazolyl tetrazolium (MTT) method, apoptotic rates were analyzed with PI/Annexin V flow cytometry, and the dynamic changes of cell metabolism were studied by using 1H NMR technology platform and high-throughput multivariate statistical analysis to reveal the changes of endogenous metabolites of SH-SY5Y cell. It was found that ginsenoside Rb1 could protect the SH-SY5Y cell by reducing apoptosis induced by glutamate and 7 metabolites of glutamic acid, taurine, acetic acid, arginine, creatine alanine, and proline were identified through orthogonal partial least squares discriminant analysis (OPLS-DA). Metaboanalyst showed taurine and hypotaurine metabolism, arginine and proline metabolism, alanine, aspartate and glutamate metabolism, D-Glutamine and D-glutamate metabolism and pyruvate metabolism were mainly involved. The results showed that ginsenoside Rb1 had a protective effect on SH-SY5Y cell by affecting various energy and amino acid metabolism.
Metabolomics based on 1H nuclear magnetic resonance (NMR) was established to explore the protection mechanism of ginsenoside Rb1 on injury of SH-SY5Y cell induced by glutamic acid (Glu). Cell viability was evaluated by methyl thiazolyl tetrazolium (MTT) method, apoptotic rates were analyzed with PI/Annexin V flow cytometry, and the dynamic changes of cell metabolism were studied by using 1H NMR technology platform and high-throughput multivariate statistical analysis to reveal the changes of endogenous metabolites of SH-SY5Y cell. It was found that ginsenoside Rb1 could protect the SH-SY5Y cell by reducing apoptosis induced by glutamate and 7 metabolites of glutamic acid, taurine, acetic acid, arginine, creatine alanine, and proline were identified through orthogonal partial least squares discriminant analysis (OPLS-DA). Metaboanalyst showed taurine and hypotaurine metabolism, arginine and proline metabolism, alanine, aspartate and glutamate metabolism, D-Glutamine and D-glutamate metabolism and pyruvate metabolism were mainly involved. The results showed that ginsenoside Rb1 had a protective effect on SH-SY5Y cell by affecting various energy and amino acid metabolism.
2019, 47(1): 59-66
doi: 10.19756/j.issn.0253-3820.181600
Abstract:
Prostate cancer is the most frequently occurred cancer in males. Phosphatase and tensin homolog (PTEN) deficiency often occurs in prostate cancer and induces metabolic reprogramming. Metabolic vulnerabilities induced by PTEN deficiency may provide therapeutic targets for cancer therapy. Here, capillary electrophoresis-mass spectrometry (CE-MS) based metabolomics analysis was used for analyzing metabolic changes induced by PTEN deficiency in prostate cancer cell DU145 and normal prostate cell RWPE1. 200 and 214 metabolites were detected, and 28 and 37 differential metabolites were authenticated in PTEN knock-downed DU145 and RWPE1 cells compared to their controls, respectively. Threonic acid levels increased, while isobutyrylcarnitine, adenosine diphosphate, N-glycolylneuraminic acid, Asp, hypotaurine levels decreased after PTEN silencing in both cell lines. The specific metabolites changes in DU145 after PTEN silencing were L-2-HG, glycerophosphocholine, thiamine, the ratio of GSH to GSSG, and all of them were increased. These metabolites can promote tumor proliferation, metastasis, and resistance to chemotherapy. Creatinine, carnosine and N-acetylneuraminic acid, which had been reported to be biomarkers of cancer diagnosis and prognosis, were regulated by PTEN deficiency. Metabolites changes induced by PTEN deficiency only or combined effect of PTEN deficiency and other cancer-related genes were identified.
Prostate cancer is the most frequently occurred cancer in males. Phosphatase and tensin homolog (PTEN) deficiency often occurs in prostate cancer and induces metabolic reprogramming. Metabolic vulnerabilities induced by PTEN deficiency may provide therapeutic targets for cancer therapy. Here, capillary electrophoresis-mass spectrometry (CE-MS) based metabolomics analysis was used for analyzing metabolic changes induced by PTEN deficiency in prostate cancer cell DU145 and normal prostate cell RWPE1. 200 and 214 metabolites were detected, and 28 and 37 differential metabolites were authenticated in PTEN knock-downed DU145 and RWPE1 cells compared to their controls, respectively. Threonic acid levels increased, while isobutyrylcarnitine, adenosine diphosphate, N-glycolylneuraminic acid, Asp, hypotaurine levels decreased after PTEN silencing in both cell lines. The specific metabolites changes in DU145 after PTEN silencing were L-2-HG, glycerophosphocholine, thiamine, the ratio of GSH to GSSG, and all of them were increased. These metabolites can promote tumor proliferation, metastasis, and resistance to chemotherapy. Creatinine, carnosine and N-acetylneuraminic acid, which had been reported to be biomarkers of cancer diagnosis and prognosis, were regulated by PTEN deficiency. Metabolites changes induced by PTEN deficiency only or combined effect of PTEN deficiency and other cancer-related genes were identified.
2019, 47(1): 67-76
doi: 10.19756/j.issn.0253-3820.181401
Abstract:
After desulfurization and dehydration treatment, natural gas is composed of methane, ethane, propane, carbon dioxide, nitrogen, hydrogen, carbon monoxide and unknown alkane components of C4 or more (denoted as C4+). The sum of the content of first seven components is more than 90% of natural gas. When the existing Raman spectral analysis methods are applied to analyze the natural gas composition, a small amount of unknown alkane components C4+ will have a greater impact on the analysis precision. On the basis of this, a novel Raman analysis method which consists of a spectral automatic decomposition algorithm and a quantitative analysis model has been developed. Based on a linear additivity of Raman spectra, the Raman spectrum of a natural gas sample can be decomposed into the sum of the Raman spectra of pure constituents and several Lorentz peaks by a nonlinear least-square optimization algorithm. The content of the unknown alkane component C4+ can be described as the area of C-H deformation vibration peak common for most alkane molecules. Samples of the training set are used to establish the model between Raman characteristic peak area and corresponding concentration for each component relative to methane. Compared with the existing Raman analysis methods, the new method solves the issue of analyzing natural gas containing unknown alkane components and has good stability and accuracy. Experiments show that the maximum absolute errors of this algorithm for methane, ethane, propane, carbon dioxide, nitrogen, hydrogen, and carbon monoxide respectively reach 0.57%, 0.37%, 0.21%, 0.07%, 0.18%, 0.04%, 0.13%, and the correlation coefficient of gas chromatographic results also reaches 0.997, 0.986, 0.991, 0.998, 0.993, 1.000, 0.995, 0.982, respectively.
After desulfurization and dehydration treatment, natural gas is composed of methane, ethane, propane, carbon dioxide, nitrogen, hydrogen, carbon monoxide and unknown alkane components of C4 or more (denoted as C4+). The sum of the content of first seven components is more than 90% of natural gas. When the existing Raman spectral analysis methods are applied to analyze the natural gas composition, a small amount of unknown alkane components C4+ will have a greater impact on the analysis precision. On the basis of this, a novel Raman analysis method which consists of a spectral automatic decomposition algorithm and a quantitative analysis model has been developed. Based on a linear additivity of Raman spectra, the Raman spectrum of a natural gas sample can be decomposed into the sum of the Raman spectra of pure constituents and several Lorentz peaks by a nonlinear least-square optimization algorithm. The content of the unknown alkane component C4+ can be described as the area of C-H deformation vibration peak common for most alkane molecules. Samples of the training set are used to establish the model between Raman characteristic peak area and corresponding concentration for each component relative to methane. Compared with the existing Raman analysis methods, the new method solves the issue of analyzing natural gas containing unknown alkane components and has good stability and accuracy. Experiments show that the maximum absolute errors of this algorithm for methane, ethane, propane, carbon dioxide, nitrogen, hydrogen, and carbon monoxide respectively reach 0.57%, 0.37%, 0.21%, 0.07%, 0.18%, 0.04%, 0.13%, and the correlation coefficient of gas chromatographic results also reaches 0.997, 0.986, 0.991, 0.998, 0.993, 1.000, 0.995, 0.982, respectively.
2019, 47(1): 77-85
doi: 10.19756/j.issn.0253-3820.171505
Abstract:
To overcome the shortcoming of traditional Raman spectral decomposition method that requires a priori information of pure spectra, a new Raman spectral decomposition algorithm based on multivariate curve resolution and Lorentz function constraint was proposed. This method was based on the bilinear model for mixture spectra, and only the mixture spectral matrix was needed to perform the analysis. It first decomposes the mixture spectra with principal component resolution, and then the evolving factor analysis was performed to find the distribution of the mixture spectral eigenvalues evolves along with the pixel direction, so that it could determine the number of components in the mixture, the range of their peaks and the initial estimation for their spectra. Finally an alternative least squares method with Lorentz function constraint was proposed to optimize the pure spectra, during the process, it first fits the pure spectra with Lorentz function, and then based on the fitted spectra, it regresses the spectra and the coefficient matrix with non-negative alternative least squares method. The above optimization process was repeatedly performed until the fit error for the mixture spectra was within the threshold. In the experimental part, the proposed algorithm was adopted to decompose the Raman spectra of the circulating fluid in an adsorption tower of a p-xylene unit, with which the relative pure spectra was obtained in the mixture fluid. Finally, with the repeated quantitative analysis experiments for its main component of p-xylene, we prove the effectiveness for the proposed algorithm.
To overcome the shortcoming of traditional Raman spectral decomposition method that requires a priori information of pure spectra, a new Raman spectral decomposition algorithm based on multivariate curve resolution and Lorentz function constraint was proposed. This method was based on the bilinear model for mixture spectra, and only the mixture spectral matrix was needed to perform the analysis. It first decomposes the mixture spectra with principal component resolution, and then the evolving factor analysis was performed to find the distribution of the mixture spectral eigenvalues evolves along with the pixel direction, so that it could determine the number of components in the mixture, the range of their peaks and the initial estimation for their spectra. Finally an alternative least squares method with Lorentz function constraint was proposed to optimize the pure spectra, during the process, it first fits the pure spectra with Lorentz function, and then based on the fitted spectra, it regresses the spectra and the coefficient matrix with non-negative alternative least squares method. The above optimization process was repeatedly performed until the fit error for the mixture spectra was within the threshold. In the experimental part, the proposed algorithm was adopted to decompose the Raman spectra of the circulating fluid in an adsorption tower of a p-xylene unit, with which the relative pure spectra was obtained in the mixture fluid. Finally, with the repeated quantitative analysis experiments for its main component of p-xylene, we prove the effectiveness for the proposed algorithm.
2019, 47(1): 86-92
doi: 10.19756/j.issn.0253-3820.181534
Abstract:
A new high performance liquid chromatography-fluorescence detection (HPLC-FLD) method was developed by fluorescence derivatization and magnetic dispersive solid phase extraction (MDSPE) technology for the determination of triclosan (TCS), β-estradiol (E2), nonylphenol (NP), and 4-octylphenol (OP). With 2'-carbonyl chloride rosamine (RHB-Cl) as precolumn derivatization reagent, the derivatization and MDSPE conditions were investigated. The results showed that the maximum derivatives were obtained after derivatizationin for 5 min in Na2CO3-NaHCO3 buffer solution at pH 9.5 at room temperature (20℃). Under the optimized conditions including using magnetic graphene oxide as MDSPE adsorbent (15 mg), extraction for 5 min, methanol/acetic acid (9:1, V/V) as elution agent, and elution for 3 min, four endocrine disruptor compound derivatives were enriched and purified. Under optimized chromatographic conditions, the four derivatives were separated within 12 min. The fluorescence excitation and emission wavelengths were set at 554 nm and 570 nm, respectively, achieving highest detection sensitivity for four endocrine disruptor compounds derivatives. The limits of detection (LODs) were in the range of 1.1-1.9 ng/L, and the limits of quantification (LOQs) were in the range of 4.0-7.5 ng/L. This method had good linearity, precision and recovery results, and also showed obvious advantages such as simplicity, rapidity and high sensitivity comparing to the reported methods. It was a convenient and validated method for the routine analysis of endocrine disruptor compounds in milk, toothpaste and waste water, and could provide a new method for food, drinking and water safety supervision.
A new high performance liquid chromatography-fluorescence detection (HPLC-FLD) method was developed by fluorescence derivatization and magnetic dispersive solid phase extraction (MDSPE) technology for the determination of triclosan (TCS), β-estradiol (E2), nonylphenol (NP), and 4-octylphenol (OP). With 2'-carbonyl chloride rosamine (RHB-Cl) as precolumn derivatization reagent, the derivatization and MDSPE conditions were investigated. The results showed that the maximum derivatives were obtained after derivatizationin for 5 min in Na2CO3-NaHCO3 buffer solution at pH 9.5 at room temperature (20℃). Under the optimized conditions including using magnetic graphene oxide as MDSPE adsorbent (15 mg), extraction for 5 min, methanol/acetic acid (9:1, V/V) as elution agent, and elution for 3 min, four endocrine disruptor compound derivatives were enriched and purified. Under optimized chromatographic conditions, the four derivatives were separated within 12 min. The fluorescence excitation and emission wavelengths were set at 554 nm and 570 nm, respectively, achieving highest detection sensitivity for four endocrine disruptor compounds derivatives. The limits of detection (LODs) were in the range of 1.1-1.9 ng/L, and the limits of quantification (LOQs) were in the range of 4.0-7.5 ng/L. This method had good linearity, precision and recovery results, and also showed obvious advantages such as simplicity, rapidity and high sensitivity comparing to the reported methods. It was a convenient and validated method for the routine analysis of endocrine disruptor compounds in milk, toothpaste and waste water, and could provide a new method for food, drinking and water safety supervision.
2019, 47(1): 93-98
doi: 10.19756/j.issn.0253-3820.171441
Abstract:
Guar gum fracturing fluid is most widely used fracturing fluid in oilfield, but it needs gel breaking and flowback after fracturing, which causes damage to the formation. The adsorption of gel-breaking solution is an important aspect of formation damage. In this work, hydroxypropyl guar gum (HPG) was selected for determining the concentration of guar gum solution. The adsorption behavior of HPG on the kaolin was studied. The determination method of HPG concentration was established by the similar structure of guar gum and cellulose. The result showed that the adsorption amount of HPG on kaolin was 7.1 mg/g, and the adsorption behavior followed the Langmuir adsorption isotherm. FTIR results showed that the HPG adsorption on kaolin was physical adsorption. XRD characterization confirmed the adsorption of HPG into kaolin inside. In summary, the adsorption of HPG onto kaolin was physical adsorption, inside adsorption and monolayer adsorption. Finally, different influencing factors (temperature, pH, salts, alcohols, polymers) were studied. The results showed that the adsorption of HPG on kaolin increased with the increase of pH value. Desorption amount of HPG on kaolin did not increase with the increase of temperature. MgCl2 and CaCl2 decreased the adsorption capacity. NaCl, KCl, Na2SO4 and Na3PO4 could increase the adsorption capacity, in which KCl had the greatest impact. The addition of monobasic alcohol did not change the amount of adsorption, while polybasic alcohol could increase the amount of adsorption. The addition of the polymer decreased the amount of adsorption.
Guar gum fracturing fluid is most widely used fracturing fluid in oilfield, but it needs gel breaking and flowback after fracturing, which causes damage to the formation. The adsorption of gel-breaking solution is an important aspect of formation damage. In this work, hydroxypropyl guar gum (HPG) was selected for determining the concentration of guar gum solution. The adsorption behavior of HPG on the kaolin was studied. The determination method of HPG concentration was established by the similar structure of guar gum and cellulose. The result showed that the adsorption amount of HPG on kaolin was 7.1 mg/g, and the adsorption behavior followed the Langmuir adsorption isotherm. FTIR results showed that the HPG adsorption on kaolin was physical adsorption. XRD characterization confirmed the adsorption of HPG into kaolin inside. In summary, the adsorption of HPG onto kaolin was physical adsorption, inside adsorption and monolayer adsorption. Finally, different influencing factors (temperature, pH, salts, alcohols, polymers) were studied. The results showed that the adsorption of HPG on kaolin increased with the increase of pH value. Desorption amount of HPG on kaolin did not increase with the increase of temperature. MgCl2 and CaCl2 decreased the adsorption capacity. NaCl, KCl, Na2SO4 and Na3PO4 could increase the adsorption capacity, in which KCl had the greatest impact. The addition of monobasic alcohol did not change the amount of adsorption, while polybasic alcohol could increase the amount of adsorption. The addition of the polymer decreased the amount of adsorption.
2019, 47(1): 99-105
doi: 10.19756/j.issn.0253-3820.181585
Abstract:
The recognition of the composition and distribution of organic matter in coal is the basis for the development of coal-based fine chemical industry. High-resolution mass spectrometry (MS) can obtain more abundant molecular information of organic matter in coal compared to routine ones. At the meantime, the large amount of data generated by high-resolution MS brings a challenge to the efficient mining of spectral information. Statistical methods can quickly complete the analysis of a large amount of data, realize data visualization and meet the needs of comprehensive scientific researches. In this study, a two-stage fractional extraction (n-hexane and methanol) was carried out on six coal samples from typical coal mines in China to obtain 12 extracts. Gas chromatography/mass spectrometry (GC/MS) and electrospray-time-of-flight mass spectrometry (ESI-TOF MS) were used to analyze the 12 extracts to explore the molecular characteristics in composition and distribution. Based on the programs tun by R language, systematic cluster analysis of MS data from the 12 extracts could quickly obtain the relative content and distribution of compounds. The clustering results were completely consistent with the actual results. It was found that n-hexane had better extraction effects on alkanes and aromatics, and methanol had a better extraction effect on oxygenates. From GC/MS data, the relative content of aromatic hydrocarbons was the highest, mainly consisting of polycyclic aromatic hydrocarbons. The relative content of ON compounds was the highest in the data from ESI-TOF/MS, because ESI at positive mode inclines to ionize basic nitrogen-containing organic compounds. In the n-hexane extract, ONS-containing compounds had the highest content. For methanol extract, ON-containing compounds had the highest content, which was related to the cleavage of C-S bond.
The recognition of the composition and distribution of organic matter in coal is the basis for the development of coal-based fine chemical industry. High-resolution mass spectrometry (MS) can obtain more abundant molecular information of organic matter in coal compared to routine ones. At the meantime, the large amount of data generated by high-resolution MS brings a challenge to the efficient mining of spectral information. Statistical methods can quickly complete the analysis of a large amount of data, realize data visualization and meet the needs of comprehensive scientific researches. In this study, a two-stage fractional extraction (n-hexane and methanol) was carried out on six coal samples from typical coal mines in China to obtain 12 extracts. Gas chromatography/mass spectrometry (GC/MS) and electrospray-time-of-flight mass spectrometry (ESI-TOF MS) were used to analyze the 12 extracts to explore the molecular characteristics in composition and distribution. Based on the programs tun by R language, systematic cluster analysis of MS data from the 12 extracts could quickly obtain the relative content and distribution of compounds. The clustering results were completely consistent with the actual results. It was found that n-hexane had better extraction effects on alkanes and aromatics, and methanol had a better extraction effect on oxygenates. From GC/MS data, the relative content of aromatic hydrocarbons was the highest, mainly consisting of polycyclic aromatic hydrocarbons. The relative content of ON compounds was the highest in the data from ESI-TOF/MS, because ESI at positive mode inclines to ionize basic nitrogen-containing organic compounds. In the n-hexane extract, ONS-containing compounds had the highest content. For methanol extract, ON-containing compounds had the highest content, which was related to the cleavage of C-S bond.
2019, 47(1): 106-111
doi: 10.19756/j.issn.0253-3820.171499
Abstract:
A photocatalytic microreactor coated with nano-TiO2 powder was prepared in this work. By using UV-LED as light source and UV-vis spectrometer as detector, a microfluidic analysis system was established. Organic phosphorus (Chlorpyrifos) in water sample was on-line detected by the microfluidic analysis system with the spectrophotometric detection of the intensely coloured phospho-molybdenum blue. Influence factors such as light intensity, flow rate and pH value of organic phosphorus sample, flow rate of ammonium molybdate with ascorbic acid were investigated and optimized. Standard phosphate solutions were measured under optimized conditions and showed a good linear relationship in the range of 0.05-5.0 mg/L. Detection limit of standard phosphate was 0.013 mg/L (3σ), which was almost the same as that of the national standard method. In this study, organic phosphorus samples with total phosphorus of 0.10-0.50 mg/L were photodegradated on-line and total phosphorus was also detected on-line. The RSDs were less than 4.0% (n=5). Chlorpyrifos of 0.05-0.50 mg/L could be photodegradated in 30 s and the errors of measurement were less than ±5%. It took only 15 min to complete the whole process of measurement including degradation of organic phosphorus sample. The microfluidic analysis system for detection of organic phosphorus has the advantage of less pollution, less time consuming and easy operation. It has good application potential in on site environmental monitoring.
A photocatalytic microreactor coated with nano-TiO2 powder was prepared in this work. By using UV-LED as light source and UV-vis spectrometer as detector, a microfluidic analysis system was established. Organic phosphorus (Chlorpyrifos) in water sample was on-line detected by the microfluidic analysis system with the spectrophotometric detection of the intensely coloured phospho-molybdenum blue. Influence factors such as light intensity, flow rate and pH value of organic phosphorus sample, flow rate of ammonium molybdate with ascorbic acid were investigated and optimized. Standard phosphate solutions were measured under optimized conditions and showed a good linear relationship in the range of 0.05-5.0 mg/L. Detection limit of standard phosphate was 0.013 mg/L (3σ), which was almost the same as that of the national standard method. In this study, organic phosphorus samples with total phosphorus of 0.10-0.50 mg/L were photodegradated on-line and total phosphorus was also detected on-line. The RSDs were less than 4.0% (n=5). Chlorpyrifos of 0.05-0.50 mg/L could be photodegradated in 30 s and the errors of measurement were less than ±5%. It took only 15 min to complete the whole process of measurement including degradation of organic phosphorus sample. The microfluidic analysis system for detection of organic phosphorus has the advantage of less pollution, less time consuming and easy operation. It has good application potential in on site environmental monitoring.
2019, 47(1): 112-118
doi: 10.19756/j.issn.0253-3820.181121
Abstract:
A novel quinoline-based cyanine derivative of CyQ was facilely synthesized by the condensation reaction of 4-methyl quinoline and dialdehyde, and its structure was characterized by 1H NMR and HRMS-ESI. Then, the target compound CyQ-cysteine (Cys) was obtained by halogen-mercapto nucleophilic substation reaction and then rearrangement reaction between CyQ and Cys. The results showed that ferric ion (Fe3+) could efficiently cause the fluorescence enhancement of CyQ-Cys, and the fluorescence intensity was linear with the Fe3+concentration in the range of 40-300 mmol/L with a regression equation of y=1.0619x + 0.01355 (R2=0.9910) and a detection limit of 10.4 μmol/L(S/N=3). In addition, by virtue of the excellent reductive properties of dark teas towards Fe3+, a NIR fluorescent method for assaying antioxidant capacity of dark teas was constructed by Fe3+-mediated off-on strategy.
A novel quinoline-based cyanine derivative of CyQ was facilely synthesized by the condensation reaction of 4-methyl quinoline and dialdehyde, and its structure was characterized by 1H NMR and HRMS-ESI. Then, the target compound CyQ-cysteine (Cys) was obtained by halogen-mercapto nucleophilic substation reaction and then rearrangement reaction between CyQ and Cys. The results showed that ferric ion (Fe3+) could efficiently cause the fluorescence enhancement of CyQ-Cys, and the fluorescence intensity was linear with the Fe3+concentration in the range of 40-300 mmol/L with a regression equation of y=1.0619x + 0.01355 (R2=0.9910) and a detection limit of 10.4 μmol/L(S/N=3). In addition, by virtue of the excellent reductive properties of dark teas towards Fe3+, a NIR fluorescent method for assaying antioxidant capacity of dark teas was constructed by Fe3+-mediated off-on strategy.
2019, 47(1): 119-128
doi: 10.19756/j.issn.0253-3820.181478
Abstract:
The multi-layer core-shell polyaniline silicon magnetic composites (Fe3O4@SiO2@PANI) were prepared in situ by oxidation polymerization-coprecipitation of silicon magnetic particles with low temperature (0℃). The Fe3O4@SiO2@PANI was used as the adsorbent for the selective magnetic solid-phase extraction (MSPE) of four trace sulfonamides (SAs) antibiotics in milk samples prior to high performance liquid chromatography with mass spectrometry (HPLC-MS). The synthesized nanocomposite sorbents were characterized by Fourier transform infrared spectra (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and vibrating sample magnetometry (VSM) techniques. The predominant variables affecting the extraction efficiency of the MSPE procedure were investigated and optimized via the response surface methodology. The optimal conditions for separation and preconcentration of trace sulfonamides in milk sample were as follows. About 15.0 mg of Fe3O4@SiO2@PANI was dispersed into 10 mL of milk sample and shaken for 40 min. Then, the Fe3O4@SiO2@PANI carrying sulfonamides was separated from the milk sample by an external magnetic field. Next, the sulfonamides were eluted from Fe3O4@SiO2@PANI with 1.0 mL of methanol aqueous solution (7:3, V/V). Under the optimized conditions, an excellent linearity was observed in the range of 10-1500 μg/L for the four sulfonamides, with the correlation coefficients of 0.9976-0.9995. The limits of detections ranged from 1.3 μg/kg to 8.2 μg/kg. The mean recoveries at three spiked levels ranged from 69.7% to 99.6%. The relative standard deviations (RSDs) of intra-day and inter-day varied from 3.4%to 4.6%and 7.8% to 10.7%, respectively. The proposed method had low background and high selectivity and sensitivity, and was successfully applied to the simultaneous determination of four kinds of trace sulfonamides antibiotics in milk sample.
The multi-layer core-shell polyaniline silicon magnetic composites (Fe3O4@SiO2@PANI) were prepared in situ by oxidation polymerization-coprecipitation of silicon magnetic particles with low temperature (0℃). The Fe3O4@SiO2@PANI was used as the adsorbent for the selective magnetic solid-phase extraction (MSPE) of four trace sulfonamides (SAs) antibiotics in milk samples prior to high performance liquid chromatography with mass spectrometry (HPLC-MS). The synthesized nanocomposite sorbents were characterized by Fourier transform infrared spectra (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and vibrating sample magnetometry (VSM) techniques. The predominant variables affecting the extraction efficiency of the MSPE procedure were investigated and optimized via the response surface methodology. The optimal conditions for separation and preconcentration of trace sulfonamides in milk sample were as follows. About 15.0 mg of Fe3O4@SiO2@PANI was dispersed into 10 mL of milk sample and shaken for 40 min. Then, the Fe3O4@SiO2@PANI carrying sulfonamides was separated from the milk sample by an external magnetic field. Next, the sulfonamides were eluted from Fe3O4@SiO2@PANI with 1.0 mL of methanol aqueous solution (7:3, V/V). Under the optimized conditions, an excellent linearity was observed in the range of 10-1500 μg/L for the four sulfonamides, with the correlation coefficients of 0.9976-0.9995. The limits of detections ranged from 1.3 μg/kg to 8.2 μg/kg. The mean recoveries at three spiked levels ranged from 69.7% to 99.6%. The relative standard deviations (RSDs) of intra-day and inter-day varied from 3.4%to 4.6%and 7.8% to 10.7%, respectively. The proposed method had low background and high selectivity and sensitivity, and was successfully applied to the simultaneous determination of four kinds of trace sulfonamides antibiotics in milk sample.
2019, 47(1): 129-137
doi: 10.19756/j.issn.0253-3820.181460
Abstract:
A method was developed for simultaneous determination of 58 kinds of fragrance allergens in acrylonitrile-butadiene-styrene (ABS) and polyvinyl chloride (PVC) plastic toys based on dissolution precipitation-gas chromatography tandem mass spectrometry (GC-MS/MS). Sample was dissolved by tetrahydrofuran, and precipitated by methanol, and then its supernatant was taken through a 0.22-μm filter membrane. After separated by DB-17MS column, the analytes were determined by tandem mass spectrometry in SRM mode, and then quantified by the external standard method. The study optimized the GC-MS parameters for determination of 58 analytes and further proved that the dissolution precipitation method had a high extraction rate by determining the recovery of the homemade positive sample. Its results showed that GC-MS/MS had strong anti-matrix background interference ability. Due to the existence of solvent effect and matrix effect, the matrix matching standard curve method should be used for quantitative analysis. The limits of quantification (LOQs) for different substances were 0.1-10 mg/kg, and the correlation coefficient (R2) was larger than 0.9926 in the linear range of 0.1-600 mg/kg. The recoveries of fragrances in ABS and PVC samples ranged from 76.9% to 129.6% and 70.3% to 126.5%, respectively. The relative standard deviations (RSD, n=6) ranged from 0.9% to 10.2% and 1.1% to 9.6%, respectively. Finally, 65 commercial toys were detected, and the contents of 10 fragrances ranged from 3.0 to 46.8 mg/kg. The method was simple, rapid, accurate, sensitive and low cost, and suitable for the detection of 58 fragrance allergens in plastic toys.
A method was developed for simultaneous determination of 58 kinds of fragrance allergens in acrylonitrile-butadiene-styrene (ABS) and polyvinyl chloride (PVC) plastic toys based on dissolution precipitation-gas chromatography tandem mass spectrometry (GC-MS/MS). Sample was dissolved by tetrahydrofuran, and precipitated by methanol, and then its supernatant was taken through a 0.22-μm filter membrane. After separated by DB-17MS column, the analytes were determined by tandem mass spectrometry in SRM mode, and then quantified by the external standard method. The study optimized the GC-MS parameters for determination of 58 analytes and further proved that the dissolution precipitation method had a high extraction rate by determining the recovery of the homemade positive sample. Its results showed that GC-MS/MS had strong anti-matrix background interference ability. Due to the existence of solvent effect and matrix effect, the matrix matching standard curve method should be used for quantitative analysis. The limits of quantification (LOQs) for different substances were 0.1-10 mg/kg, and the correlation coefficient (R2) was larger than 0.9926 in the linear range of 0.1-600 mg/kg. The recoveries of fragrances in ABS and PVC samples ranged from 76.9% to 129.6% and 70.3% to 126.5%, respectively. The relative standard deviations (RSD, n=6) ranged from 0.9% to 10.2% and 1.1% to 9.6%, respectively. Finally, 65 commercial toys were detected, and the contents of 10 fragrances ranged from 3.0 to 46.8 mg/kg. The method was simple, rapid, accurate, sensitive and low cost, and suitable for the detection of 58 fragrance allergens in plastic toys.
2019, 47(1): 138-146
doi: 10.19756/j.issn.0253-3820.181516
Abstract:
Water circulation system with the almost same element composition and socket type were adopted in coral Acropora culture under different seawater pH conditions and the experimental data of the relationship between boron isotopic compositions of coral and seawater pH were obtained by thermoelectric ionization mass spectrometer. From the correlations between αcarb-3 of coral and pH of cultured seawater, αcarb-3 was not a constant but related to pH, indicating that B(OH)3 also incorporated carbonate. Therefore, the theoretical formula could not be used to calculate the seawater pH value from the δ11Bcarb value of the measured marine biological carbonate. The method using the empirical equations obtained experimentally to calculate the seawater pH value would be an alternative. In addition, a mixed precipitation of inorganic CaCO3 and Mg(OH)2 was found in aquaculture tanks with high pH value and the δ11B of the solid was significantly higher than that of cultured seawater. The result indicated that the presence of Mg(OH)2 had a significant effect on the boron isotope fractionation, which deserved our attention.
Water circulation system with the almost same element composition and socket type were adopted in coral Acropora culture under different seawater pH conditions and the experimental data of the relationship between boron isotopic compositions of coral and seawater pH were obtained by thermoelectric ionization mass spectrometer. From the correlations between αcarb-3 of coral and pH of cultured seawater, αcarb-3 was not a constant but related to pH, indicating that B(OH)3 also incorporated carbonate. Therefore, the theoretical formula could not be used to calculate the seawater pH value from the δ11Bcarb value of the measured marine biological carbonate. The method using the empirical equations obtained experimentally to calculate the seawater pH value would be an alternative. In addition, a mixed precipitation of inorganic CaCO3 and Mg(OH)2 was found in aquaculture tanks with high pH value and the δ11B of the solid was significantly higher than that of cultured seawater. The result indicated that the presence of Mg(OH)2 had a significant effect on the boron isotope fractionation, which deserved our attention.
2019, 47(1): 147-154
doi: 10.19756/j.issn.0253-3820.181504
Abstract:
A novel highly sensitive and specific method for detection of ricin toxin (RT) based on bio-barcode combined with hybridization chain reaction (HCR) amplification was developed. Functional gold nanoparticles (GNPs) were coated with anti-ricin polyclonal antibodies (pAb) and barcode DNA. The "mAb-RT-pAb/AuNPs/barcode DNA" sandwich structure was formed by co-identification with the anti-ricin monoclonal antibody (mAb), and HCR was further carried out by using barcode DNA as an initiation chain probe for triggering the chain-triggered biotin label, which resulted in a long double-stranded DNA with repeating units. Immediately, streptavidin labeled horseradish peroxidase (SA-HRP) was combined with biotin on long strand DNA. Finally, the chemiluminescence values were detected through adding substrates of luminol and hydrogen peroxide. The results showed that the linear range of RT was 0.61 ng/mL-5000 ng/mL, and the limit of detection (LOD) was 0.52 ng/mL(S/N=3). This method showed a wide detection range and a low detection limit. The recoveries of spiked samples in milk and water samples ranged from 83.4% to 112.4%, and the relative standard deviations (RSDs) ranged from 2.2% to 5.4%. This method exhibited great application prospects in food drinking water safety control and prevention of bioterrorism attacks.
A novel highly sensitive and specific method for detection of ricin toxin (RT) based on bio-barcode combined with hybridization chain reaction (HCR) amplification was developed. Functional gold nanoparticles (GNPs) were coated with anti-ricin polyclonal antibodies (pAb) and barcode DNA. The "mAb-RT-pAb/AuNPs/barcode DNA" sandwich structure was formed by co-identification with the anti-ricin monoclonal antibody (mAb), and HCR was further carried out by using barcode DNA as an initiation chain probe for triggering the chain-triggered biotin label, which resulted in a long double-stranded DNA with repeating units. Immediately, streptavidin labeled horseradish peroxidase (SA-HRP) was combined with biotin on long strand DNA. Finally, the chemiluminescence values were detected through adding substrates of luminol and hydrogen peroxide. The results showed that the linear range of RT was 0.61 ng/mL-5000 ng/mL, and the limit of detection (LOD) was 0.52 ng/mL(S/N=3). This method showed a wide detection range and a low detection limit. The recoveries of spiked samples in milk and water samples ranged from 83.4% to 112.4%, and the relative standard deviations (RSDs) ranged from 2.2% to 5.4%. This method exhibited great application prospects in food drinking water safety control and prevention of bioterrorism attacks.
2019, 47(1): 155-162
doi: 10.19756/j.issn.0253-3820.181511
Abstract:
The application of boronic acid affinity chromatography in glycoprotein/glycopeptide enrichment tends to be more and more mature. The enrichment selectivity, biocompatibility, and facile operation protocol are key points for efficient enrichment methods. In this work, a novel boronic acid functionalized material (TYBA material) was prepared by using Thiol-yne click chemistry. The TYBA material was proved to be successfully synthesized by infrared (IR) characterization. The glycopeptide/glycoprotein enrichment selectivity of the TYBA material was evaluated. Matrix assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) was applied for evaluation of glycopeptide enrichment selectivity. Taking digest of horseradish peroxidase (HRP) and immunoglobulin G (IgG) as samples, 11 and 8 glycopeptides were identified with improved signals after TYBA material enrichment, respectively. High abundant non-glycopeptides were well removed from the eluting fraction. The result indicated high glycopeptide enrichment selectivity of TYBA material. A mixture of HRP and bovine serum albumin (BSA) enzymatic solution (molar ratio 1:10) was used as the sample and 8 glycopeptide signals were identified after enrichment. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) was applied for evaluation d of enrichment selectivity of glycoprotein. The mixture of HRP, IgG, BSA and RNaseB proteins was used as model sample, and the results showed that TYBA material had high glycoprotein enrichment selectivity. The application of TYBA material in the analysis of real biosample was also evaluated by human plasma. The results indicated the TYBA material could be used in large scale glycoprotein analysis.
The application of boronic acid affinity chromatography in glycoprotein/glycopeptide enrichment tends to be more and more mature. The enrichment selectivity, biocompatibility, and facile operation protocol are key points for efficient enrichment methods. In this work, a novel boronic acid functionalized material (TYBA material) was prepared by using Thiol-yne click chemistry. The TYBA material was proved to be successfully synthesized by infrared (IR) characterization. The glycopeptide/glycoprotein enrichment selectivity of the TYBA material was evaluated. Matrix assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) was applied for evaluation of glycopeptide enrichment selectivity. Taking digest of horseradish peroxidase (HRP) and immunoglobulin G (IgG) as samples, 11 and 8 glycopeptides were identified with improved signals after TYBA material enrichment, respectively. High abundant non-glycopeptides were well removed from the eluting fraction. The result indicated high glycopeptide enrichment selectivity of TYBA material. A mixture of HRP and bovine serum albumin (BSA) enzymatic solution (molar ratio 1:10) was used as the sample and 8 glycopeptide signals were identified after enrichment. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) was applied for evaluation d of enrichment selectivity of glycoprotein. The mixture of HRP, IgG, BSA and RNaseB proteins was used as model sample, and the results showed that TYBA material had high glycoprotein enrichment selectivity. The application of TYBA material in the analysis of real biosample was also evaluated by human plasma. The results indicated the TYBA material could be used in large scale glycoprotein analysis.
2019, 47(1): 163-168
doi: 10.19756/j.issn.0253-3820.181542
Abstract:
Hollow cathode lamps (HCL) are the most commonly used excitation sources for hydride generation-atomic fluorescence spectrometry (HG-AFS). In general, there was lead (Pb) interference in selenium (Se) HCL. This kind of light source interference affected the accuracy of the detection results when Se and Pb simultaneously were determined by HG-AFS. In this work, the effects of light source interference were discussed and analyzed, and a light source interference factor method was proposed to correct the spectral interference. This method had many advantages including simple operation and high reliability, and appropriately reduced the purity of the cathode of the light source. The spectral interference of Se HCL was discussed. The conditions of simultaneous determination of Se and Pb in K3[Fe(CN)6]-KBH4-HCl chemical generation system were optimized, and the influence of Pb interference in HCL of Se was discussed. In the concentration range of 2-50 μg/L, the detection limit of Se was 0.034 μg/L (r=0.9995), and the detection limit of Pb was 0.019 μg/L (r=0.9997). The method precisions were 0.85% (10 μg/L, Se,n=9) and 0.47% (10 μg/L, Pb, n=9), respectively. The feasibility of the method was confirmed by the simultaneous detection of national standard sample rice GBW10010 (GSB-1), wheat GBW10011 (GSB-2) and soy flour. The results of the light source calibration were consistent with the standard values.
Hollow cathode lamps (HCL) are the most commonly used excitation sources for hydride generation-atomic fluorescence spectrometry (HG-AFS). In general, there was lead (Pb) interference in selenium (Se) HCL. This kind of light source interference affected the accuracy of the detection results when Se and Pb simultaneously were determined by HG-AFS. In this work, the effects of light source interference were discussed and analyzed, and a light source interference factor method was proposed to correct the spectral interference. This method had many advantages including simple operation and high reliability, and appropriately reduced the purity of the cathode of the light source. The spectral interference of Se HCL was discussed. The conditions of simultaneous determination of Se and Pb in K3[Fe(CN)6]-KBH4-HCl chemical generation system were optimized, and the influence of Pb interference in HCL of Se was discussed. In the concentration range of 2-50 μg/L, the detection limit of Se was 0.034 μg/L (r=0.9995), and the detection limit of Pb was 0.019 μg/L (r=0.9997). The method precisions were 0.85% (10 μg/L, Se,n=9) and 0.47% (10 μg/L, Pb, n=9), respectively. The feasibility of the method was confirmed by the simultaneous detection of national standard sample rice GBW10010 (GSB-1), wheat GBW10011 (GSB-2) and soy flour. The results of the light source calibration were consistent with the standard values.
