Sustained release dosage forms dissolution behavior prediction: A study of matrix tablets using NIR spectroscopy

The objective of this study was to predict dissolution behavior of sustained release theophylline matrix tablets using near infrared (NIR) diffuse reflectance spectroscopy and multivariate calibration models. Eudragit NE 30D was used as a granulation binder to prepare theophylline sustained release tablets. A total of 117 tablets from 5 batches containing different proportions of Eudragit NE 30D were scanned using a NIR spectrometer. The release characteristics of the tablets were investigated in the acetate buffer for 4 h. The percentage release at 1, 2, 3 and 4 h was used to build the PLS calibration models. The Mahalanobis distance in principal component space and the 2nd derivative transformation were used for sample selection prior to building a four 4-factor partial least square (PLS) calibration models for predicting 1, 2, 3 and 4 h release rates. For PLS1 h, the standard error of calibration (SEC), and standard error of prediction (SEP) were 2.8 and 3.4%. For PLS2 h, the SEC and SEP were 2.7 and 3.5%. For PLS3 h, the SEC and SEP were 2.6 and 3.5% and for PLS4 h, the SEC and SEP were 3.0 and 3.5%, respectively. For the first time, NIR spectroscopy was successfully applied to predict drug release in the matrix tablets by correlating dissolution profile of each batch to its corresponding Eudragit NE 30D variation in tablet composition.