This work developed a new method for determination of dipyrone (DIP) in oral pharmaceutical formulations, through the use of near infrared (NIR) transflectance measurements and multivariate calibration. The studied range varied from 300.0 to 569.2 mg mL-1. The best PLS (partial least squares) model was obtained with two latent variables and the root mean square errors of calibration and prediction were 1.1 and 1.0 mg mL-1, respectively. The proposed method was validated in accordance with ANVISA, the Brazilian regulatory agency, and ICH, being considered selective, linear, precise, accurate and robust. By comparison with the main alternatives, iodimetric titration and HPLC, this method is simpler, non-destructive, does not use reagents or solvents and does not produce chemical waste. Besides, its rapidity is considered the major advantage over the other methods, since only about 50 s were spent per assay.
multivariate calibration; quality control; PLS; metamizole; near infrared spectroscopy
