Romero-Torres Saly, Pérez-Ramos José D, Morris Kenneth R, Grant Edward R
Department of Chemistry, Purdue University, 425 Central Drive, West Lafayette, IN 47907, USA.
J Pharm Biomed Anal. 2005 Jun 15;38(2):270-4. doi: 10.1016/j.jpba.2005.01.007. Epub 2005 Feb 23.
We report new results suggesting the feasibility of Raman spectrometry as a tool by which to examine the variability of tablet coatings. Our experiments feature a probe that can operate with a revolving laser focus to average content and coating non-uniformity. Raman spectral changes are correlated with tablet exposure times in a pan coater by means of partial least squares (PLS) multivariate analysis. Statistical models are found to be improved by pre-processing schemes that emphasize spectral changes while minimizing the effects of background light scattering and fluorescence. These pre-processing techniques include multiplicative scatter correction (MSC) and standard normal variate (SNV) transformation, used in concert with Savitzky-Golay second derivative smoothing (SGSD). The two approaches give comparable results yielding R2 values for PLS calibration and cross-calibrated prediction variance regression of 0.999 and 0.997, respectively. Correlation results and model residual values demonstrate that Raman spectroscopy serves sensitively to reflect the coating thickness of the tablets studied.
我们报告了新的结果，表明拉曼光谱法作为一种检测片剂包衣变异性的工具具有可行性。我们的实验采用了一种探头，该探头可以通过旋转激光焦点来平均含量和包衣不均匀性。通过偏最小二乘法（PLS）多变量分析，拉曼光谱变化与在锅式包衣机中的片剂暴露时间相关。通过强调光谱变化同时最小化背景光散射和荧光影响的预处理方案，发现统计模型得到了改进。这些预处理技术包括乘法散射校正（MSC）和标准正态变量（SNV）变换，并与Savitzky-Golay二阶导数平滑（SGSD）协同使用。这两种方法给出了可比的结果，PLS校准的R2值和交叉校准预测方差回归的R2值分别为0.999和0.997。相关性结果和模型残差值表明，拉曼光谱能够灵敏地反映所研究片剂的包衣厚度。
