Patil S T, Sundaresan M, Bhoir I C, Bhagwat A M
Shri. C. B. Patel Research Centre For Chemistry and Biological Sciences, 2nd Floor, Mithibai College Building, Vile Parle (West), Mumbai 400 056, India.
Talanta. 1998 Sep;47(1):3-10. doi: 10.1016/s0039-9140(98)00045-9.
A reproducible and fast method has been developed for the assay of acetaminophen, methocarbamol, and diclofenac sodium in bulk and drug forms using packed column supercritical fluid chromatography employing internal standard method. The analytes were resolved by elution with supercritical fluid carbon dioxide doped with 11.1% (v/v) methanol on a Shendon-Phenyl (250x4.6 mm) 5 mum column with detection monitored spectrophotometrically at 225 nm. The densities and polarities of the mobile phase were optimised from the effects of pressure, temperature and modifier concentration on chromatograhic figures like retention time (t(R), min), retention factor (k(')) etc. Modifier concentration proved to be the most effective means for changing both retention and selectivity. Calibration data and recovery of the drug from spiked concentrations were determined to assess the viability of the method. The supercritical fluid chromatography (SFC) method was directly compared to an HPLC assay, developed in the laboratory, of the same analytes. With respect to speed and use of organic solvents SFC was found to be superior, while in all other aspects the results were similar to HPLC. The method has been successfully used for the assay of two formulations containing a combination of (A) acetaminophen and methocarbamol and (B) acetaminophen and diclofenac sodium. There was no interference from excipients. The present work validates the recent proposition that supercritical fluid chromatography using CO(2) and modifiers is a viable, faster alternative to reverse phase HPLC.
已开发出一种可重现且快速的方法，采用填充柱超临界流体色谱法并结合内标法，用于测定原料药及制剂中对乙酰氨基酚、美索巴莫和双氯芬酸钠的含量。在Shendon-Phenyl（250×4.6 mm）5μm色谱柱上，使用掺杂11.1%（v/v）甲醇的超临界流体二氧化碳进行洗脱，以分离分析物，并在225 nm处进行分光光度检测。通过考察压力、温度和改性剂浓度对诸如保留时间（t(R)，分钟）、保留因子（k(')）等色谱参数的影响，优化了流动相的密度和极性。结果表明，改性剂浓度是改变保留和选择性的最有效手段。通过测定校准数据和加标浓度下药物的回收率来评估该方法的可行性。将超临界流体色谱（SFC）方法与实验室开发的用于相同分析物的HPLC方法进行了直接比较。在速度和有机溶剂使用方面，SFC方法表现更优，而在其他所有方面，结果与HPLC方法相似。该方法已成功用于测定两种制剂，其中一种含有对乙酰氨基酚和美索巴莫的组合，另一种含有对乙酰氨基酚和双氯芬酸钠的组合。辅料无干扰。本研究验证了最近的观点，即使用CO(2)和改性剂的超临界流体色谱法是一种可行、更快的反相HPLC替代方法。
