A novel capacitive sensor for pazufloxacin mesilate (pazufloxacin) determination was developed by electropolymerizing p-aminobenzene sulfonic (p-ABSA) and molecularly imprinted polymers (MIPs), which was synthesized t...A novel capacitive sensor for pazufloxacin mesilate (pazufloxacin) determination was developed by electropolymerizing p-aminobenzene sulfonic (p-ABSA) and molecularly imprinted polymers (MIPs), which was synthesized through thermal radical copolymerization of metharylic acid (MAA) and ethyl-ene glycol dimethacrylate (EGDMA) in the presence of pazufloxacin template molecules, on the gold electrode surface. Furthermore, 1-dedecanethiol was used to insulate the modified electrode. Alter-nating current (ac) impedance experiments were carried out with a Model IM6e to obtain the capaci-tance responses. Under the optimum conditions, the sensor showed linear capacitance response to pazufloxacin in the range of 5 ng·mL-1 to 5 μg·mL-1 with a relative standard deviation (RSD) 5.3% (n=7) and a detection limit of 1.8 ng·mL-1. The recoveries for different concentration levels of pazufloxacin samples varied from 94.0% to 102.0%. Electrochemical experiments indicated the capacitive sensor exhibited good sensitivity and selectivity and showed excellent parameters of regeneration and stabil-ity.展开更多
Laser flash photolysis and sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE) experiments were carried out to study the photosensitive damage induced by pazufloxacin(PAX) and the protection of lysozym...Laser flash photolysis and sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE) experiments were carried out to study the photosensitive damage induced by pazufloxacin(PAX) and the protection of lysozyme(Lyso) by ferulic acid(FCA), an active antioxidant. Transient absorption spectra revealed electron transfer from Lyso and FCA to 3PAX*, with respective bimolecular reaction rate constants of 6.3×107 and 1.4×1010 dm3/(mol s). A pulse radiolysis study was also performed to investigate the formation of Lyso radical cations. Results showed that FCA effectively inhibited the cross-linking of protein induced by fluoroquinolones. Finally, a mechanism of the protective effect of FCA on Lyso was proposed.展开更多
目的基于药动/药效(pharmacokinetic/pharmacodynamic,PK/PD)理论,应用蒙特卡洛模拟(Monte Carlo simulation,MCS)评价及优化不同病原菌感染时帕珠沙星的给药方案。方法将12名健康志愿受试者分为3组,分别给予300、500和1000 mg3种不同...目的基于药动/药效(pharmacokinetic/pharmacodynamic,PK/PD)理论,应用蒙特卡洛模拟(Monte Carlo simulation,MCS)评价及优化不同病原菌感染时帕珠沙星的给药方案。方法将12名健康志愿受试者分为3组,分别给予300、500和1000 mg3种不同剂量的帕珠沙星,以高效液相色谱法测得血药浓度,进而求出PK参数。用琼脂二倍稀释法确定大肠埃希菌、肺炎克雷伯菌、铜绿假单胞菌、金黄色葡萄球菌、表皮葡萄球菌和肺炎链球菌6种临床分离菌株物的最低抑菌浓度以进行PD研究。根据PK/PD研究结果,以AUC_(0-24)/MIC作为帕珠沙星的PK/PD指数(靶值为30、100和125),通过蒙特卡洛模拟得出不同给药方案的达标概率(probability of target attainment,PTA)和累积响应百分率(cumulative fraction of response,CFR),评价出最佳给药方案。结果以CFR>90%的给药方案作为临床最佳给药方案,蒙特卡洛模拟10000次的结果得出,帕珠沙星在1000 mg的给药剂量下对肺炎链球菌的CFR可达到92.33%,在500和1000 mg的给药剂量下对表皮葡萄球菌的CFR可达到90.11%和93.79%;对大肠埃希菌、肺炎克雷伯菌、金黄色葡萄球菌和铜绿假单胞菌的CFR均小于90%。结论在表皮葡萄球菌感染时推荐使用500 mg qd的帕珠沙星;在日剂量为1000 mg时帕珠沙星对肺炎链球菌的感染有很好的效果,对大肠埃希菌、肺炎克雷伯菌、金黄色葡萄球菌和铜绿假单胞菌的抑制效果不佳,可作为辅佐治疗药物。不同致病菌感染时所需要的给药剂量存在明显差异,根据PK/PD理论以及蒙特卡洛模拟可为帕珠沙星临床最佳给药方案的制定提供依据。展开更多
基金Supported by the National Natural Science Foundation of China (Grant No. 20675064)the Natural Science Foundation of Chongqing City (Grant No. CSTC-2004BB4149 and 2005BB4100)High Technology Project Foundation of Southwest University (Grant No. XSGX02).
文摘A novel capacitive sensor for pazufloxacin mesilate (pazufloxacin) determination was developed by electropolymerizing p-aminobenzene sulfonic (p-ABSA) and molecularly imprinted polymers (MIPs), which was synthesized through thermal radical copolymerization of metharylic acid (MAA) and ethyl-ene glycol dimethacrylate (EGDMA) in the presence of pazufloxacin template molecules, on the gold electrode surface. Furthermore, 1-dedecanethiol was used to insulate the modified electrode. Alter-nating current (ac) impedance experiments were carried out with a Model IM6e to obtain the capaci-tance responses. Under the optimum conditions, the sensor showed linear capacitance response to pazufloxacin in the range of 5 ng·mL-1 to 5 μg·mL-1 with a relative standard deviation (RSD) 5.3% (n=7) and a detection limit of 1.8 ng·mL-1. The recoveries for different concentration levels of pazufloxacin samples varied from 94.0% to 102.0%. Electrochemical experiments indicated the capacitive sensor exhibited good sensitivity and selectivity and showed excellent parameters of regeneration and stabil-ity.
基金supported by the National Natural Science Foundation of China(21173252)
文摘Laser flash photolysis and sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE) experiments were carried out to study the photosensitive damage induced by pazufloxacin(PAX) and the protection of lysozyme(Lyso) by ferulic acid(FCA), an active antioxidant. Transient absorption spectra revealed electron transfer from Lyso and FCA to 3PAX*, with respective bimolecular reaction rate constants of 6.3×107 and 1.4×1010 dm3/(mol s). A pulse radiolysis study was also performed to investigate the formation of Lyso radical cations. Results showed that FCA effectively inhibited the cross-linking of protein induced by fluoroquinolones. Finally, a mechanism of the protective effect of FCA on Lyso was proposed.
文摘目的基于药动/药效(pharmacokinetic/pharmacodynamic,PK/PD)理论,应用蒙特卡洛模拟(Monte Carlo simulation,MCS)评价及优化不同病原菌感染时帕珠沙星的给药方案。方法将12名健康志愿受试者分为3组,分别给予300、500和1000 mg3种不同剂量的帕珠沙星,以高效液相色谱法测得血药浓度,进而求出PK参数。用琼脂二倍稀释法确定大肠埃希菌、肺炎克雷伯菌、铜绿假单胞菌、金黄色葡萄球菌、表皮葡萄球菌和肺炎链球菌6种临床分离菌株物的最低抑菌浓度以进行PD研究。根据PK/PD研究结果,以AUC_(0-24)/MIC作为帕珠沙星的PK/PD指数(靶值为30、100和125),通过蒙特卡洛模拟得出不同给药方案的达标概率(probability of target attainment,PTA)和累积响应百分率(cumulative fraction of response,CFR),评价出最佳给药方案。结果以CFR>90%的给药方案作为临床最佳给药方案,蒙特卡洛模拟10000次的结果得出,帕珠沙星在1000 mg的给药剂量下对肺炎链球菌的CFR可达到92.33%,在500和1000 mg的给药剂量下对表皮葡萄球菌的CFR可达到90.11%和93.79%;对大肠埃希菌、肺炎克雷伯菌、金黄色葡萄球菌和铜绿假单胞菌的CFR均小于90%。结论在表皮葡萄球菌感染时推荐使用500 mg qd的帕珠沙星;在日剂量为1000 mg时帕珠沙星对肺炎链球菌的感染有很好的效果,对大肠埃希菌、肺炎克雷伯菌、金黄色葡萄球菌和铜绿假单胞菌的抑制效果不佳,可作为辅佐治疗药物。不同致病菌感染时所需要的给药剂量存在明显差异,根据PK/PD理论以及蒙特卡洛模拟可为帕珠沙星临床最佳给药方案的制定提供依据。