1.Simultaneous determination of seven residual solvents in clopidogrel bisulfate by headspace gas chromatography
Lu CHEN ; Xue GENG ; Qiujie LIN ; Shanying CAI ; Zanmin CHEN
Drug Standards of China 2024;25(4):387-391
Objective:A gas chromatography(GC)method was established for the simultaneous determination of seven residual solvents in clopidogrel bisulfate,including methanol,acetone,isopropanol,dichloromethane,n-hexane,tetrahydrofuran and methylbenzene.Methods:The analysis was performed on an Agilent DB-1 capillary column(30 m ×0.32 mm,3.0 μm)under the programmed temperature.The carrier gas was high purity nitrogen,and the flow rate was 4.0 mL·min-1 with constant flow control.The detector was a hydrogen flame ionization detector(FID).The inlet temperature was 200 ℃,the detector temperature was 270 ℃ and the split ratio was 5∶1.The temperature of headspace injector was 85 ℃,and the equilibrium time was 20 min.Results:Seven residual solvents were separated completely.The linear relationship between peak area and the concentration range of seven residual solvents were good enough(r>0.9993).The results of specificity,precision and recovery met the requirements.Conclusion:This method can be used for the determination of residual organic solvents in clopidogrel bisulfate.
2.Advances in haplotype analysis technique.
Shuangshuang LI ; Yingxin ZHANG ; Chengming FAN ; Yuhong CHEN ; Chuanliang DENG ; Zanmin HU
Chinese Journal of Biotechnology 2018;34(6):852-861
Haplotype is the combination of a series of genetic mutations that coexist on a single chromosome, each of which has its own unique haplotypes. As a common data analysis method, the analysis of haplotype is effective for the localization of heterozygosis SNPs on single chromosome, the excavation of disease genes and the search of maladies treatments. It mainly includes indirect computational inferential method and direct experimental method. In this review we introduced various haplotype analysis methods and applications, especially two important ones: single-molecule dilution and contiguity-preserving transposition sequencing common technology. Meanwhile, further research prospects on haplotype sequencing were proposed.
3.Advances in several important antimicrobial lipopeptids from Bacillus spp.
Daoming LI ; Ying WANG ; Chao CHEN ; Mingbai ZENG ; Qianru LI ; Qingyun JIA ; Xiuli LIU ; Yongyue HOU ; Chengming FAN ; Yuhong CHEN ; Zanmin HU
Chinese Journal of Biotechnology 2022;38(5):1768-1783
Bacillus spp. are probiotics and can secrete a variety of natural antimicrobiol active substances, of which lipopeptides are an important class. Up to now, about 90 lipopeptides have been identified, and most of them are cyclic lipopeptides. surfactin, iturin, fengycin, bacillomycin and polymyxins are widely studied, and the first three have huge potential for application due to their properties of surfactants and anti-fungal, anti-bacterial, anti-viral, anti-tumor and anti-inflammatory functions. In this paper, the research progress in the structure, function, synthesis regulation, separation, purification and production of surfactin, iturin and fengycin was reviewed. Synthetic biology is a vital means to increase the yield of lipopeptides, and in the future, lipopeptides can be used in crop cultivation, animal farming, food, medicine and petroleum industries as well as environmental protection. Future research should be strengthened on the discovery of new lipopeptides, synthesis of high-activity lipopeptides, economical production of lipopeptides on a large scale and their safety evaluation.
Anti-Bacterial Agents
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Anti-Infective Agents/pharmacology*
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Bacillus
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Bacillus subtilis
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Lipopeptides/pharmacology*
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Peptides, Cyclic/pharmacology*