喹诺酮类抗生素在蒸发光散射检测器中响应因子的一致性考察

目的考察不同的喹诺酮类抗生素在蒸发光散射检测器(ELSD)中的响应因子是否一致，进而评价利用ELSD迅速测定该类药物含量的可行性。方法用HPLC-ELSD法测定了几种喹诺酮类抗生素（依诺沙星、左氧氟沙星、环丙沙星、洛美沙星和加替沙星）的进样量与响应取双对数的线性方程。色谱条件：YMC-Pack ODS-AM 柱 (150 mm×4.6 mm ID，5 μm)；流动相 0.5%三乙胺水溶液(三氟醋酸调至pH 2.5)-乙腈(48∶12);流速0.6 mL·min^-1。检测器条件：漂移管温度117 ℃，气体流速3.0 L·min^-1。结果5种物质的线性方程间无显著性差异（P>0.05）。结论5种不同的喹诺酮类抗生素在ELSD中的响应因子一致，可尝试用HPLC-ELSD法建立该类药物的一类新药基准品。

Analysis of the response factors of different quinolones detected by evaporative light-scattering detector

AIM: To analyze the response factors of different quinolone antibiotics detected by evaporative light-scattering detector (ELSD). METHODS: The response factors of five different quinolones (enoxacin, levofloxacin, ciprofloxacin, lomefloxacin and gatifloxacin) detected by ELSD were determined by using a YMC-Pack ODS-AM cloumn (150 mm x 4.6 mm ID, 5 microns) as analytical column and 0.5% triethylamine (adjusting pH 2.5 with trifluoroacetic acid)-acetonitrile (48:12) as mobile phase at a flow rate of 0.6 mL.min-1, the temperature of the drift tube was set at 117 degrees C, and the flow of carrier gas at 3.0 L.min-1. Detector responses (A) and the amount of injection of each substance (m) were fitted to the logarithmic regression: log A = b log m + log a. RESULTS: The linear regression equation obtained were: enoxacin: Y = 1.0799X + 2.7611, r2 = 0.9996; levofloxacin: Y = 1.0913X + 2.7235, r2 = 0.9997; ciprofloxacin: Y = 1.0828X + 2.7523, r2 = 0.9994; lomefloxacin: Y = 1.0891X + 2.7391, r2 = 0.9993; gatifloxacin: Y = 1.0878X + 2.7392, r2 = 0.9995. The differences between them were negligible. CONCLUSION: Different quinolones can give the same responses with ELSD detection. So, the HPLC-ELSD methods can be applied to the determination of new substances by using another substance as reference.