Research institute of Pharmaceutical Sciences, Faculty of Pharmacy, University of Karachi, Karachi, Pakistan.
J Sep Sci. 2013 Oct;36(19):3176-83. doi: 10.1002/jssc.201300104. Epub 2013 Aug 28.
A highly sensitive LC method with UV detection has been developed for the simultaneous determination of coadministered drugs captopril, piroxicam, and amlodipine in bulk drug, pharmaceutical formulations, and human serum at the isosbestic point (235 nm) and at individual λmax (220, 255, and 238 nm, respectively) by programming the detector with time to match the individual analyte's chromophore, which enhanced the sensitivity with linear range. The assay involved an isocratic elution of analytes on a Bondapak C18 (10 μm, 25 × 0.46 cm) column at ambient temperature using a mobile phase of methanol/water 80:20 at pH 2.9 and a flow rate of 1.0 mL/min. Linearity was found to be 0.25-25, 0.10-6.0, and 0.20-13.0 μg/mL with correlation coefficient >0.998 and detection limits of 7.39, 3.90, and 9.38 ng/mL, respectively, whereas calibration curves for wavelength-programmed analysis were 0.10-6.0, 0.04-2.56, and 0.10-10.0 μg/mL with correlation coefficient >0.998 and detection limits of 5.79, 2.68, and 3.87 ng/mL, respectively. All the validated parameters were in the acceptable range. The recovery of drugs was 99.32-100.39 and 98.65-101.96% in pharmaceutical formulation and human serum, respectively, at the isosbestic point and at individual λmax . This method is applicable for the analysis of drugs in bulk drug, tablets, serum, and in clinical samples without interference of excipients or endogenous serum components.
已经开发出一种高度敏感的 LC 方法，该方法具有 UV 检测功能，可在等色点（235nm）和各个 λmax（分别为 220、255 和 238nm）处同时测定同时给予的药物卡托普利、吡罗昔康和氨氯地平的原料药、药物制剂和人血清中的药物。通过编程检测器以与各个分析物的生色团匹配的时间来进行测定，从而提高了灵敏度和线性范围。该测定法在环境温度下，使用甲醇/水 80:20（pH2.9）作为流动相，在 Bondapak C18（10μm，25×0.46cm）柱上进行等度洗脱，流速为 1.0mL/min。发现线性范围为 0.25-25、0.10-6.0 和 0.20-13.0μg/mL，相关系数>0.998，检测限分别为 7.39、3.90 和 9.38ng/mL，而波长程序分析的校准曲线为 0.10-6.0、0.04-2.56 和 0.10-10.0μg/mL，相关系数>0.998，检测限分别为 5.79、2.68 和 3.87ng/mL。所有验证的参数均在可接受范围内。在等色点和各个 λmax 处，药物在药物制剂和人血清中的回收率分别为 99.32-100.39%和 98.65-101.96%。该方法适用于原料药、片剂、血清和临床样品中药物的分析，不存在赋形剂或内源性血清成分的干扰。
