利用胶束电动色谱技术用于抗生素测定

采用毛细管胶束电动色谱技术对阿莫西林、氯唑两林、头孢氨苄、头孢噻肟、头孢唑林5种抗生素进行分离．18kV电压下，在溶有100mmol／LSI）S的硼酸盐缓冲溶液（20mmol／L，pH-8．9）中，采用二极管阵列检测器．在9min内可以完成对此5种抗生素的分离检测．线性范围0．1～250μg／mL．相关系数为0．9976～0．9994，检测限为0．01～0．13μg／mL．运用此方法对3种药物形式的抗生素进行同时检测．日间和日内的RSDs分别为3．95％～8．12％和1．51％～2．86％。迁移时间的日间和日内的RSDs分别为0．47％～1．11％和0.032％～0.295％．在尿样的测定中，日问和日内的RSDs分别为1．31％～6.07％和0.66％～7．65％，回收率为90％～110％．此外．还对分离条件对抗生素的迁移行为的影响做了理论探讨．

Simultaneous Determination of Antibiotics by Micellar Electrokinetic Capillary Chromatography

The micellar electrokinetic capillary chromatographic(MECC) separation of amoxicillin, cloxacillin, cefalexin, cefotaxime and cefazolin with diode array detection was investigated and their simultaneous detection of the antibiotics in urine was performed. Electrophoresis was performed at 18 kV with a borate buffer (20 mmol/L, pH 8. 9) containing sodium dodecyl sulfate (SDS, 100 mmol/L) and the detection was carried out at 254 nm. These five antibiotics could be baseline-separated less than 9 min. Linearity in 0.1-250 μg/mL could be constructed with the correlation coefficient of 0. 997 6-0. 999 4, and the limits of detection range were from 0.01 to 0.13 μg/mL at a signal-to-noise ratio of 3. The method was successfully used for simultaneous determination of the mixture of three commercial drug samples. The results of detection were achieved with a perfect separation and the RSDs of 1.51%-2.86% for intra-day assay and RSDs of 3. 95%-8. 12% for inter-day assay. It was worth noting that the migration time of the practical samples was with RSDs of 0.032%-0.295% for intra-day assay and RSDs of 0. 47% -1.11% for inter-day assay. When applied to diluted urine sample detection, recovery from 90% to110%, and RSDs of 0. 66%-7. 65% for intra-day assay and 1.31%-6.07% for inter-day assay could be obtained, respectively. The explanation about their migration behavior related to the separate conditions was also stated.