Journal of the Brazilian Chemical Society
Print version ISSN 0103-5053
CARNEIRO, Renato L. and POPPI, Ronei J.. A quantitative method using near infrared imaging spectroscopy for determination of surface composition of tablet dosage forms: an example of spirolactone tablets. J. Braz. Chem. Soc. [online]. 2012, vol.23, n.8, pp.1570-1576. Epub Aug 30, 2012. ISSN 0103-5053. http://dx.doi.org/10.1590/S0103-50532012005000022.
In this work, near infrared (NIR) imaging spectroscopy was employed in the study of the distribution of the active pharmaceutical ingredient (API) spironolactone and its excipients in tablets. Analyses were performed using 50 µm spatial resolution to analyze 16 mm2 of each standard tablet. Interval partial least squares models were used for API and excipients quantification in every pixel in order to obtain concentration maps for each compound. It was obtained errors of quantification between 0.49 and 1.26% when performed the cross-validation using spectral average of each tablet. These calibration models were used to predict individual concentration of each compound in the tablet, in every pixel. The average concentration of all pixels, for each compound yield errors, was between 0.05 and 1.06%. These results indicate that the models were able to quantify all compounds in each pixel. This approach is necessary since it is not possible to know the real concentration of each compound in the pixels.
Keywords : image spectroscopy; near infrared; spironolactone; content uniformity.