Content uniformity studies in tablets by NIR-CI

Near infrared chemical imaging (NIR-CI) is attracting growing interest in pharmaceutical analysis by virtue of its ability to provide a wealth of information from a single sample. Among others, NIR-CI has enabled the determination of the quantitative composition and distribution of acetylsalicylic (ASA) from the analysis of commercial tablets. In this work, we analyzed ASA commercial tablets of four different brands purchased at local chemists. The nominal ASA concentration for the brands was calculated from the nominal content and averaged weight of tablets. The tablets were found to span an ASA concentration range of 71-82%, and to differ in size and composition between brands. The API content and its homogeneity distribution were determined by applying quantitative algorithm to global hyperspectral image of ten tablets. Multivariate curve resolution-alternating least squares (MCR-ALS) is used to quantify each pixel in the images to obtain appropriate concentration maps. No prior calibration or reference data were needed for quantitation and results are close to the nominal content used as reference. Application to an image for 10 tablets and an individual tablet quantitation of the API allowed us to obtain the Accepted Value (AV) as defined by the European Pharmacopoeia. We conclude that all brands meet the pharmacopoeia specifications.