Nagaraja P, Murthy K C, Rangappa K S
Department of Studies in Chemistry, Mysore University, India.
J Pharm Biomed Anal. 1998 Jul;17(3):501-6. doi: 10.1016/s0731-7085(97)00237-9.
A rapid, sensitive and simple spectrophotometric method is proposed for the determination of hydrolysis products of paracetamol (PRL) and phenacetin (PHN) with sodium 1,2-naphthoquinone-4-sulphonate and cetyltrimethyl ammonium bromide (CTA) in alkaline medium. The absorbances are measured at 570 and 500 nm and the molar absorptivities found to be 1.118 x 10(4) and 4.54 x 10(3) l mol-1 cm-1 for PRL and PHN, respectively. The coloured species conforms to Beer's law over the range 1-20 micrograms ml-1 for PRL and 2-24 micrograms ml-1 of PHN. The sensitivity is enhanced by the addition of CTA. The method is successfully employed for determination of PRL or PHN in various pharmaceutical preparations and laboratory made tablets and results have been statistically compared with those obtained by the official method.
提出了一种快速、灵敏且简便的分光光度法，用于在碱性介质中用1,2-萘醌-4-磺酸钠和十六烷基三甲基溴化铵（CTA）测定对乙酰氨基酚（PRL）和非那西丁（PHN）的水解产物。在570和500 nm处测量吸光度，发现PRL和PHN的摩尔吸光系数分别为1.118×10⁴和4.54×10³ l·mol⁻¹·cm⁻¹。有色物质在PRL为1 - 20微克/毫升和PHN为2 - 24微克/毫升的范围内符合比尔定律。CTA的加入提高了灵敏度。该方法成功用于各种药物制剂和实验室自制片剂中PRL或PHN的测定，并且已将结果与官方方法获得的结果进行了统计学比较。
