Optical Radiation Standards, National Physical Laboratory, K. S. Krishnan Road, New Delhi-110012, India.
Drug Test Anal. 2009 Jun;1(6):275-8. doi: 10.1002/dta.47.
The determination of moisture content in pharmaceuticals is very important as moisture is mainly responsible for the degradation of drugs. Degraded drugs have reduced efficacy and could be hazardous. The objective of the present work is to replace the Karl Fischer (KF) titration method used for moisture analysis with a method that is rapid, involves no toxic materials and is more effective. Diffuse reflectance infrared (IR) spectroscopy, which is explored as a potential alternative to various approaches, is investigated for moisture analysis in 5-fluorouracil, an anticancer drug. A total of 150 samples with varying moisture content were prepared in laboratory by exposing the drug at different relative humidities, for different time intervals. Infrared spectra of these samples were collected with a Fourier transform infrared (FTIR) spectrophotometer using a diffuse reflectance accessory. Reference moisture values were obtained using the Karl Fischer titration method. A number of calibration models were developed using the partial least squares (PLS) regression method. A good correlation was obtained between predicted IR values and reference values in the calibration and validation set. The derived calibration curve was used to predict moisture content in unknown samples. The results show that IR spectroscopy can be used successfully for the determination of moisture content in the pharmaceutical industry.
药品中水分含量的测定非常重要，因为水分主要是导致药物降解的原因。降解的药物疗效降低，而且可能具有危害性。本工作的目的是用一种快速、不使用有毒物质且更有效的方法替代卡尔费休（KF）滴定法用于水分分析。漫反射红外（IR）光谱法作为各种方法的潜在替代方法进行了研究，用于分析抗癌药物 5-氟尿嘧啶中的水分。通过在不同的相对湿度下和不同的时间间隔下使药物暴露，在实验室中制备了总共 150 个具有不同水分含量的样品。使用漫反射附件，通过傅里叶变换红外（FTIR）分光光度计收集这些样品的红外光谱。使用卡尔费休滴定法获得参考水分值。使用偏最小二乘（PLS）回归方法开发了多个校准模型。在校准和验证集中，预测的 IR 值与参考值之间得到了很好的相关性。得出的校准曲线用于预测未知样品中的水分含量。结果表明，IR 光谱法可成功用于制药行业中水分含量的测定。
