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Chinese Journal of Chromatography
2018, Vol. 36, No. 3
Online: 08 March 2018

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Activity review of Association of Women Scholars in Chromatography ZHAO Xinying, QU Feng 2018, 36 (3):  181-184.  DOI: 10.3724/SP.J.1123.2018.01035 Abstract ( 412 )   [Full Text(HTML)] () PDF (819KB) ( 39 )   Since the founding of "Association of Women Scholars in Chromatography" in April 2016, a total of 14 academic conferences and technical communication forums have been held, including 28 reports and more than 600 participants. The Special Issue of Chinese Journal of Chromatography on Celebration of International Working Women's Day by Female Chromatographic Scientists was firstly published in March 2017, which contains 22 papers with women scholars as first or corresponding authors. In March 2018, 20 papers are published. For two years, we have built the WeChat group for women scholars, 14 times association activities have been reported in real time by WeChat. All activities are warmly concerned by many scholars and colleagues. On the occasion of the 2nd anniversary, association activities are reviewed. Thanks to all the women scholars for their active participation, and thanks to all supports and helps from colleagues.

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Preparation of cobalt phthalocyanine functionalized polymer monolith and application to enrichment of transferrin glycopeptides ZHANG Wenjuan, SONG Naizhong, JIA Qiong 2018, 36 (3):  185-189.  DOI: 10.3724/SP.J.1123.2017.11045 Abstract ( 498 )   [Full Text(HTML)] () PDF (863KB) ( 49 )   Poly(glycidyl methacrylate-ethyleneglycol dimethacrylate) (Poly(GMA-EDMA)) monolith functionalized with cobalt phthalocyanine tetracarboxylic acid (CoPcTc) was prepared. The monolith was used for transferrin (Tf) glycopeptide enrichment. By taking advantage of hydrogen bonds between isoindole subunits of phthalocyanine and glycans and coordination interaction between cobalt and glycopeptides, the monolithic material was efficient and selective. After enrichment of transferrin through the functionalized monolith, 17 glycopeptides were identified by electrospray ionization quadrupole time-of-flight mass spectrometry. When the concentration of transferrin was reduced to 8.8×10-10mol/L, three glycopeptides could still be obtained. The present method has great potential for trace sample analysis.

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Determination of six ultraviolet filters in cosmetics by high performance liquid chromatography coupled with solid-phase extraction based on graphene sponge WANG Xuemei, WANG Juan, DU Tongtong, MA Xiaomin, LU Xiaoquan 2018, 36 (3):  190-194.  DOI: 10.3724/SP.J.1123.2017.11006 Abstract ( 642 )   [Full Text(HTML)] () PDF (2579KB) ( 90 )   A method for the simultaneous determination of six UV filters in cosmetics by high performance liquid chromatography (HPLC) coupled with solid-phase extraction (SPE) based on graphene sponge (GS) was established. The samples were extracted with methanol by ultrasonic, then cleaned up by home-made SPE cartridges and eluted with acetone. The six UV filters were separated on an Agilent Zorbax SB-C18 column (150 mm×4.6 mm, 5 μm). Methanol-water (95:5, v/v) was used as mobile phase and the detection wavelength was 340 nm. The results showed that the limits of detection (LODs, S/N=3) and the limits of quantification (LOQs, S/N=10) of the six UV filters were 0.08-1.82 μg/L and 0.26-6.07 μg/L, respectively. The correlation coefficients (r) were greater than 0.999 except 2-(2'-hydroxy-5'-methyl-phenyl) benzotriazole (r>0.997). The recoveries of the six UV filters were 61.1%-119.0%, and the relative standard deviations (RSDs) were less than 1% (n=6) at the three spiked levels of 20, 50 and 100 μg/L. The method is simple, rapid, sensitive and repeatable, and is suitable for the determination of the UV filters in cosmetics.

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Applications on therapeutic monoclonal antibody analysis by capillary electrophoresis CHEN Hongxu, QU Feng 2018, 36 (3):  195-208.  DOI: 10.3724/SP.J.1123.2018.01015 Abstract ( 718 )   [Full Text(HTML)] () PDF (2172KB) ( 557 )   Therapeutic monoclonal antibodies play an important role in biopharmaceuticals, and gradually become one of the main directions of the development of biological medicine. The quality control of monoclonal antibodies has also become the focus of global biopharma companies and regulatory agencies. Capillary electrophoresis has become an important tool in the analysis of monoclonal antibodies with multi-modes and high resolution. In this paper, we reviewed the application of capillary gel electrophoresis, capillary isoelectric focusing and capillary zone electrophoresis on the analysis of purity, isoelectric point/charge heterogeneity and N-glycan profiling of therapeutic monoclonal antibodies.

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Research progress of pyrolysis combined with ion chromatography NI Lijun, ZHANG Fangfang, LUAN Shaorong 2018, 36 (3):  209-215.  DOI: 10.3724/SP.J.1123.2017.11048 Abstract ( 482 )   [Full Text(HTML)] () PDF (1067KB) ( 99 )   Ion chromatography (IC) is widely used in the anions and cations analysis for its rapid detection and high sensitivity. With the increasing requirement of detecting organic of samples, developing a suitable pretreatment method is important. Pyrolysis apparatus can be operated automatically and easily with high sensitivity and good repeatability. In the paper, the basic principles and types of burners are introduced. The pyrolysis combined with ion chromatography (pyrolysis-IC) are applied in biology, petroleum, coal, materials, environment and other organic samples. The further development of pyrolysis-IC are also introduced.

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Development of metal-organic framework composites in sample pretreatment MENG Zhichao, ZHANG Lu, HUANG Yanfeng 2018, 36 (3):  216-221.  DOI: 10.3724/SP.J.1123.2017.11042 Abstract ( 566 )   [Full Text(HTML)] () PDF (1599KB) ( 212 )   In recent years, a new type of multi-functional porous material, metal-organic frameworks (MOFs), is emerging. MOFs are formed by coordination of metal ions or metal clusters with oxygen or nitrogen and contain organic ligands porous skeleton structure. Compared with other traditional inorganic porous materials, MOFs have many advantages such as high specific surface area, large porosity, good thermal stability and diversified structure and function. They are widely used in the fields of gas storage, catalysis, adsorption and separation. In recent years, the applications of MOF composites in sample pretreatment have aroused great interest and widespread concern. Due to the assembly of MOFs and different functional materials, such as polymers, carbon-based materials and magnetic materials, the performance of MOF composites are better than the original MOFs. This review summarizes the applications of MOF composites in sample pretreatment technique in recent years, focuses on the applications of MOFs composites in solid phase microextraction (SPME), solid phase extraction (SPE) and magnetic solid phase extraction (MSPE).

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Efficient adsorption and removal of diclofenac sodium from water with quaternary ammonium functionalized metal-organic frameworks WEI Yu, WEI Cuixiang, XIA Yan 2018, 36 (3):  222-229.  DOI: 10.3724/SP.J.1123.2017.11038 Abstract ( 467 )   [Full Text(HTML)] () PDF (4031KB) ( 74 )   A quaternary ammonium functionalized MIL-101(Cr) named MIL-101(Cr)-NMe3 was synthesized and explored as a novel adsorbent for the fast removal of diclofenac sodium (DCF) in water. The adsorption process of kinetics, adsorption isotherms, thermodynamics, and adsorbent regeneration were investigated. And the effects of key parameters such as pH value and ionic strength on the adsorption of DCF were also studied. The results showed that the adsorption of DCF on MIL-101(Cr)-NMe3 was very fast. Most of DCF were adsorbed in the first 30 min. The adsorption kinetics of DCF on MIL-101(Cr)-NMe3 obeyed pseudo-second-order kinetics. The adsorption isotherms of DCF on MIL-101(Cr)-NMe3 fitted well to the Langmuir adsorption model. And the maximum adsorption capacity was 310.6 mg/g at 20℃. The analysis of the adsorption mechanism showed that the electrostatic interaction and π-π stacking interaction between DCF and MIL-101(Cr)-NMe3 were responsible for the efficient adsorption. Regeneration experiments indicated that the used MIL-101(Cr)-NMe3 was recycled at least five times without significant loss of adsorption capacity. The fast adsorption kinetics, high adsorption capacity, and excellent reusability made MIL-101(Cr)-NMe3 attractive for removal DCF from aqueous solution.

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A cross-sequence labeling equipment for high-throughput proteome based on pseudo-isobaric dimethyl labeling LIU Jianhui, ZHANG Xiaodan, ZHOU Yuan, SHAN Yichu, FANG Fei, ZHANG Lihua, ZHANG Yukui 2018, 36 (3):  230-236.  DOI: 10.3724/SP.J.1123.2017.11040 Abstract ( 414 )   [Full Text(HTML)] () PDF (1368KB) ( 81 )   Facing the needs of multidimensional and multi-sample proteome quantification in the field of biology and precision medicine, high-throughput quantitative labeling and analysis have become the trend in recent years. A novel cross-sequence labeling equipment for high-throughput proteome based on pseudo-isobaric dimethyl labeling (pIDL-StageTip) was established. The equipment needs only simple devices and centrifugal force. The throughput of quantitative labeling is effectively increased, and the controllability of the two-step labeling reaction time at the terminals of the peptides and the ease of operation are ensured. By optimizing the labeling conditions of NaBD3CN and NaBH3CN under acidic conditions respectively, labeling efficiency of the standard proteolysis achieved 100% and labeling selectivity was more than 95%. Even in the complex human proteome, the labeling efficiency was greater than 99% and the labeling selectivity was 100%. The quantitative method based on the equipment showed high quantitative accuracy and precision. The equipment provides a reliable solution for quantitative proteome labeling with high operability, accuracy, and throughput.

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Preparation of zirconia nanoparticles deposited cotton fibers and their application in the rapid enrichment of phosphopeptides YU Qiongwei, FANG Kaimin, HE Xiaomei, ZHENG Jie, FENG Yuqi 2018, 36 (3):  237-244.  DOI: 10.3724/SP.J.1123.2017.11055 Abstract ( 409 )   [Full Text(HTML)] () PDF (2565KB) ( 50 )   A kind of cotton-based fibrous adsorbent, zirconia nanoparticles coated cotton fiber (ZrO2-CF), was successfully prepared by liquid-phase deposition of zirconia nanoparticles on the surface of cotton fiber. And the ZrO2-CF fibrous adsorbent was packed in pipet tips for the enrichment of phosphopeptide by pipetting up and down within 2 min, which was simple and fast. Nine phosphopeptides were identified from the digestion of β-casein after ZrO2-CF extraction. ZrO2-CF exhibited good selectivity in the enrichment of phosphopeptides from the digestion mixture of β-casein and BSA (molar ratio is 1:100) in which four phosphopeptides were identified. And it also showed excellent extraction efficiency in actual biological samples such as non-fat milk and human serum in which four and nine phosphopeptides were identified, respectively.

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Preparation of immobilized β-glucuronidase enzyme reactor for the analysis of O-glucuronides of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol WANG Ting, YAO Ermin, DENG Nan, BIAN Yangyang, LIU Pingping, ZHANG Ke, CHEN Qiansi, LI Bin 2018, 36 (3):  245-252.  DOI: 10.3724/SP.J.1123.2017.11050 Abstract ( 350 )   [Full Text(HTML)] () PDF (2649KB) ( 101 )   An immobilized β-glucuronidase enzyme reactor (IMER) based on organic-silica gel hybridized capillary column was prepared by the sol-gel method with acrylamide (AAM) as the organic functional monomer. The effects of the amounts of tetramethyl orthosilicate (TMOS), 3-glycidoxypropyltrimethoxysilane (γ-MAPS), acrylamide (AAM), polyethylene glycol (PEG), and the water bath temperature on the quality of the microscopic structure were studied. After optimization,the monolithic column with good permeability and high mechanical strength was obtained. Then β-glucuronidase was covalently immobilized, and the hydrolysis efficiency of the β-glucuronidase IMER was investigated. As the substrate, O-glucuronides of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL-O-Gluc) were hydrolyzed at room temperature, indicating the high hydrolysis efficiency of the β-glucuronidase IMER, which demonstrated its high potential for the high throughput analysis of tobacco metabolites in the future.

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Preparation of MIL-53(Fe)@polydopamine@Fe3O4 magnetic composite for magnetic solid-phase extraction of sulfonylurea herbicides in environmental water DENG Yulan, LI Aotian, WANG Yanfei, SUN Peng, SU Ping, YANG Yi 2018, 36 (3):  253-260.  DOI: 10.3724/SP.J.1123.2017.11041 Abstract ( 533 )   [Full Text(HTML)] () PDF (3535KB) ( 172 )   Polydopamine (PDA) and MIL-53(Fe) modified Fe3O4 particles (MIL-53(Fe)@PDA@Fe3O4 magnetic composite) were prepared by simple one-pot solvothermal method. The obtained composite was introduced to rapidly extract four kinds of sulfonylurea herbicides (SUHs) from environmental water samples by magnetic solid-phase extraction (MSPE). Then the herbicides were analyzed by a high performance liquid chromatographic system equipped with a photodiode array detector. The mobile phase was a mixture of acetonitrile and water containing 0.01% (v/v) trifluoroacetic acid, and the detection wavelength was 233 nm. Significant extraction parameters were optimized to improve the extraction efficiency. Under the optimum conditions (5 mL desorption solvent of acetone, 4.5 min extraction time, 60 mg adsorbent dosage, 0.5 g NaCl and the pH 3 of the solution), the developed method showed good linearities with correlation coefficients (r) no less than 0.9980. The limits of detection (LODs, S/N=3) of the four SUHs were 0.28-0.77 μg/L. The method was successfully used to determine four SUHs in three kinds of environmental water samples with satisfactory recoveries ranging from 78.8% to 109.7%. Therefore, the MIL-53(Fe)@PDA@Fe3O4 magnetic composite is efficient and has good potential for the extraction of SUHs.

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Chiral separation of four β-blocker enantiomers using high performance liquid chromatography-tandem mass spectrometry based on amylase derivative chiral stationary phases and investigation on their separation mechanism QIAN Zheyuan, ZHANG Mingyong, LI Shengni, HONG Zhanying, CHAI Yifeng 2018, 36 (3):  261-267.  DOI: 10.3724/SP.J.1123.2017.11009 Abstract ( 505 )   [Full Text(HTML)] () PDF (912KB) ( 130 )   A high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method based on amylose derivatives as chiral stationary phases (CSPs) for the chiral separation of four β-blocker enantiomers (propanolol, metoprolol, arotinolol and carvedilol) was established. The effects of different CSPs, volume fractions of mobile phase modifiers and mobile phase additives, column temperatures and flow rates on the chiral separation of the four β-blocker enantiomers were evaluated. Baseline separation of the four β-blockers enantiomers was obtained on a Chiralpak AD-H chiral column using the mobile phase of n-hexane-ethanol-diethylamine (20:80:0.03, v/v/v) at a flow rate of 0.550 mL/min and a column temperature of 40℃. The resolutions of the enantiomers for propanolol, metoprolol, arotinolol and carvedilol were 1.37, 1.80, 2.09 and 4.70, respectively. The separation mechanism of the four β-blocker enantiomers was investigated by thermodynamic analysis and enantiomeric structure analysis. The chiral separation was all enthalpy controlled, and the cave structure of the chiral stationary phase played an important role on the separation. The method provides reference for further studies of the β-blocker enantiomers.

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Identification of the impurities in o-chlorophenyl cyclopentyl ketone samples by high performance liquid chromatography-hybrid ion trap/time-of-flight mass spectrometry and preparation of o-chlorophenyl cyclopentyl ketone standard MA Xiaomeng, JIN Lan, LI Yaning, ZHENG Hui, WEI Yun 2018, 36 (3):  268-277.  DOI: 10.3724/SP.J.1123.2017.11034 Abstract ( 440 )   [Full Text(HTML)] () PDF (1063KB) ( 68 )   A method for the identification of relevant impurities in illegal o-chlorophenyl cyclopentyl ketone drug was developed. Identification of impurities could help regulation of this illegal drug and allow the sources of samples of the drug to be identified. An efficient and effective method for qualitatively analyzing samples using high performance liquid chromatography-hybrid ion trap/time-of-flight mass spectrometry (HPLC-IT/TOF MS) was developed. The o-chlorophenyl cyclopentyl ketone fragmentation pathway during HPLC-MSn was determined by analyzing a standard by HPLC-IT/TOF MS. The optimized HPLC-IT/TOF MS method allowed two impurities in o-chlorophenyl cyclopentyl ketone samples to be identified. According to the exact mass data of MSn and the element composition analysis, two impurities were identified as o-chlorobenzoic acid anhydride and 1,2-di-o-chlorobenzoylcyclopentene. The synthetic route of the o-chlorophenyl cyclopentyl ketone samples was proposed by analysis of these impurities. The established method made it easy to identify impurities and find the source of this illegal drug. A method for the preparation an o-chlorophenyl cyclopentyl ketone reference standard from actual samples using preparative HPLC was also developed. The mobile phase was methanol-water (85:15, v/v) and flow rate was 8 mL/min. The purity of the obtained standards, determined by analytical HPLC, was 99.53%. This method is simple, efficient, and can be used for the preparation of other illegal drugs.

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Rapid identification of flavonoid compounds in Pericarpium Citri Reticulatae by online extraction-high performance liquid chromatography-diode array detection-quadrupole time-of-flight mass spectrometry TONG Chaoying, PENG Mijun, SHI Shuyun 2018, 36 (3):  278-284.  DOI: 10.3724/SP.J.1123.2017.11031 Abstract ( 503 )   [Full Text(HTML)] () PDF (1159KB) ( 90 )   A simple method was developed for the rapid extraction, separation and identification by online extraction (OLE) coupled with high performance liquid chromatography-diode array detection-quadrupole time-of-flight mass spectrometry (HPLC-DAD-QTOF-MS). For OLE strategy, a guard column filled with Pericarpium Citri Reticulatae powder (2.0 mg) was connected to manual injection valve by replacing the sample loop. Components were directly extracted and transferred to HPLC-DAD-QTOF-MS system by mobile phases without any extra operation. In comparison with offline heat-reflux extraction, OLE strategy presented higher extraction efficiency. A total of twenty-four flavonoid compounds were detected from Pericarpium Citri Reticulatae according to their retention times, UV spectra, accurate molecular masses, and fragment ions in MS/MS spectra. Neoeriocitrin, limocitrin-3-O-(3-hydroxy-3-methylglutarate)-glucoside and its isomer were discovered for the first time. It is concluded that the developed method offers new perspectives for the rapid separation and identification of natural products.

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Simultaneous determination of six estrogens in dairy products by high performance liquid chromatography-triple quadrupole-ion trap mass spectrometry coupled with matrix solid-phase dispersion and solid phase extraction HAN Shuying, YU Huimin, SONG Yilin, DENG Haishan, CHAI Chuan, CHI Yumei 2018, 36 (3):  285-291.  DOI: 10.3724/SP.J.1123.2017.11043 Abstract ( 541 )   [Full Text(HTML)] () PDF (1359KB) ( 91 )   Matrix solid-phase dispersion (MSPD) and solid-phase extraction (SPE) were respectively developed for the pretreatment six estrogens in milk powder and liquid milk. It was implied that MSPD was suitable for the treatment of milk powder, while SPE was suitable for liquid milk treatment. Based on the optimized pretreatment procedures, the method for the simultaneous determination of the six estrogens in different dairy products was established by high performance liquid chromatography-triple quadrupole-ion trap mass spectrometry (HPLC-Q-TRAP-MS). The proposed method provided low limits of detection (LODs, 0.01-0.05 mg/L) and limits of quantification (LOQs, 0.05-0.10 mg/L), wide linearity range of 0.1-200 mg/L (except for estriol of 0.1-20 mg/L) with excellent correlation coefficients (R2)> 0.99. The average recoveries of the six estrogens in milk powder pretreated by MSPD ranged from 71.8% to 106.0% with RSD of 1.6%-9.2% (n=3), while the corresponding average recoveries in liquid milk pretreated by SPE ranged from 70.3% to 108.4% with RSD of 2.0% and 11.0% (n=3) with spiking levels of 1.0, 5.0, and 10 mg/kg, respectively. This sensitive and reliable method meets the demand for the analysis of trace estrogen residues in complex matrices.

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A novel dispersive liquid-liquid microextraction method with high performance liquid chromatography for detection of 2,6-dimethylaniline in lidocaine hydrochloride injection WANG Xuanxuan, LI Xiao, XIAO Yuxiu 2018, 36 (3):  292-298.  DOI: 10.3724/SP.J.1123.2017.11049 Abstract ( 520 )   [Full Text(HTML)] () PDF (1887KB) ( 108 )   A novel hexafluoroisopropanol (HFIP)-octanol supramolecular solvent (SUPRAS) based dispersive liquid-liquid microextraction (DLLME) method was developed for the determination of 2,6-dimethylaniline (2,6-DMA) in lidocaine hydrochloride injection coupled with high performance liquid chromatography-ultraviolet detection (HPLC-UV). n-Octanol was selected as extraction solvent while HFIP was served as dispersing agent, self-assembly inducer of n-octanol as well as density-regulating agent of n-octanol. The HFIP-octanol SUPRAS displays reverse micellar aggregate structures (2-6 μm) with hydrophilic inner cores and is located in the bottom phase of the system after phase separation, which not only facilitates the efficient extraction and enrichment of polar 2,6-DMA, but also simplifies the extraction process. Several parameters influencing the extraction efficiency of 2,6-DMA were investigated and optimized. Under optimum conditions (0.4%(v/v) n-octanol, 5% (v/v) HFIP, vortex for 3 s at 60 W, standing for 3 min, centrifugation for 3 min at 3000 r/min, sample solution pH 9), the novel DLLME-HPLC method shows good linearity for quantitative detection of 2,6-DMA in the range of 1-100 μg/L (R=0.9989). The limit of detection (LOD) was 0.33 μg/L. The enrichment factor (EF) reached about 63. Intra-day and inter-day precisions (n=3) were all below 2.5%. The recoveries were from 93.9% to 100.8%. The results demonstrate that the novel DLLME-HPLC method is suitable for the accurate quantitative determination of 2,6-DMA in lidocaine hydrochloride injection with advantages of simplicity, rapidness, high efficiency and environmental friendliness, and may own high potential in future prospects.

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Simultaneous determination of nine typical anions in fire explosive residues by ion chromatography GAN Ziqiong, LIU Junjun, TANG Shengli 2018, 36 (3):  299-302.  DOI: 10.3724/SP.J.1123.2017.11030 Abstract ( 483 )   [Full Text(HTML)] () PDF (837KB) ( 80 )   A novel method was developed for the simultaneous determination of nine typical anions (Cl-, NO2-, ClO3-, NO3-, CO32-, SO42-, S2O32-, SCN-and ClO4-) in explosive residues by ion chromatography (IC). A high capacity anion-exchange IonPac AS20 column (250 mm×4 mm) was used for the separation of the nine anions with gradient elution of KOH. The injection volume was 20 μL, the column temperature was 40℃, and the flow rate was 1.20 mL/min. Inhibitory conductivity detections were adopted in the determinations. Good linearities were found for all the nine anions in their respective ranges. The correlation coefficients were greater than 0.999. The method was applied to the determination of the inorganic ions in explosive residues. The average recovery of the nine ions ranged from 92.5% to 101.3%. The relative standard deviations of the nine anions ranged from 1.86% to 2.79% (n=6). The method is simple, quick, selective and sensitive and can meet the requirement of the analysis.

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Separation and identification of Fischer-Tropsch wax by high temperature gas chromatography-mass spectrometry GAI Qingqing, LIU Congyun, ZHAO Shuai, DONG Haifeng, ZHAO Xinying 2018, 36 (3):  303-308.  DOI: 10.3724/SP.J.1123.2017.11052 Abstract ( 485 )   [Full Text(HTML)] () PDF (1240KB) ( 72 )   Fischer-Tropsch (FT) wax is an important material produced from FT synthesis reactions. In this study, an improved separation and identification method for FT wax by high temperature gas chromatography (HTGC) coupled with cold-on-column (without pretreatment) was developed. In our improved separation procedure, the carrier gas was changed to helium and a long chromatographic column was adapted for use at high temperature. The n-alkanes in FT wax were well separated from other unknown components and the heavy components with carbon numbers higher than C90 could be eluted. Unknown components of the FT wax fraction were confirmed as alkanes, alkenes and oxygenated compounds by using HTGC-mass spectrometry. These results improve our understanding of the FT synthesis process and increase our detailed knowledge of FT products.

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Determination of peptide antibiotics in animal food by capillary electrochromatography coupled with laser induced fluorescence LEI Xiaoyun, SONG Yunping, LI Xinuo, ZHANG Bingyu, WU Xiaoping 2018, 36 (3):  309-316.  DOI: 10.3724/SP.J.1123.2017.12001 Abstract ( 413 )   [Full Text(HTML)] () PDF (964KB) ( 66 )   A rapid and sensitive method was established for the analysis of peptide antibiotics (bacitracin, polymyxin B and colistin) in animal food by capillary electrochromatography (CEC) coupled with laser induced fluorescence (LIF) using 4-fluoro-7-nitro-2,1,3-benzoxadiazole (NBD-F) as fluorogenic reagent. Peptide antibiotics were derivatized by NBD-F in 50 mmol/L borate buffer (pH 7.5) for 45 min at 60℃. The fluorescence derivatives of peptide antibiotics were separated on a packed phenyl capillary column with a mobile phase consisting of acetonitrile-potassium phosphate (pH 5.0, 10 mmol/L) (55:45, v/v) at the flow rate of 0.02 mL/min. A supplementary pressure of 3.8 MPa and a separation voltage of -10 kV were applied. The limits of detection (LODs, S/N=3) were 5.0-10.0 ng/mL, which fulfilled the requirement of maximum residue limits for examined peptide antibiotics. The method was applied to detect peptide antibiotics in milk and feed stuffs. The spiked recoveries of the three peptide antibiotics were 72.9%-112.4%. The method shows some advantages on the simpler pretreatment and higher sensitivity, which can be of great benefit to the residual analysis of the veterinary drugs.

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Preparation of Au@4-nitrothiophenol@Ag@bovine serum albumin internal surface-enhanced Raman scattering tags and its application in cell Raman imaging ZHAI Xueping, YOU Huiyan 2018, 36 (3):  317-324.  DOI: 10.3724/SP.J.1123.2017.11027 Abstract ( 457 )   [Full Text(HTML)] () PDF (6038KB) ( 138 )   This study explored a strategy of replacing the surface stabilizer of cetyltrimethylammonium bromide (CTAB) on the tag surface with bovine serum albumin (BSA) and developed a BSA coated Au@4-nitrothiophenol(NT)@Ag internal surface-enhanced Raman scattering (SERS) tag Au@NT@Ag@BSA. The Au@NT@Ag@BSA tag retained the monodispersity and high sensitivity of the original tag, while significantly improving the signal stability and biocompatibility. Furthermore, labeling and Raman spectroscopic imaging of SMMC7721 lung cancer cells were realized by the incubation of the cells with the Au@NT@Ag@BSA SERS tags. The results demonstrated that the proposed Au@NT@Ag@BSA internal SERS tags had good potential for in vivo imaging applications.