RESUMO
A three-way calibration strategy has been used to develop a simple method for drug quantitation in intact pharmaceutical tablets. The experimental design defined for the three-way calibration gathers a large variation in drug concentration (15-85% w/w) and compaction pressure (100-500 MPa). These could be process variable ranges during the development of a pharmaceutical formulation following the quality by design (QbD) approach. When a large variation in both chemical and physical variables is defined, the traditional two-way calibration strategies, such as partial least squares (PLS), do not allow the obtaining of multivariate model with good predictive ability (nonlinear predictions and prediction error over 8% w/w). The presented strategy uses parallel factor analysis (PARAFAC) to deconvolute the spectra in scores associated with drug concentration variation, and loadings related with wavelength range and compaction range. The PARAFAC deconvolution was followed by multiple linear regression (MLR) to obtain the simple calibration model with a better predictive ability on the whole compaction pressure range (prediction error less than 1.4% w/w). The proposed three-way strategy can be easily designed and executed, obtaining a multivariate analytical method more robust than using a traditional two-way modeling technique.
Assuntos
Preparações Farmacêuticas/química , Preparações Farmacêuticas/normas , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Espectroscopia de Luz Próxima ao Infravermelho/normas , Calibragem/normas , Análise Multivariada , Preparações Farmacêuticas/análise , ComprimidosRESUMO
The content uniformity of low dose products is a major concern in the development of pharmaceutical formulations. Near infrared spectroscopy may be used to support the design and optimization of potent drug manufacturing processes through the analysis of blends and tablets in a relatively short time. A strategy for the selection of concentration ranges in the development of multivariate calibration is presented, evaluating the detection and quantitation limits of the obtained multivariate models. The strategy has been applied to the determination of an active principle in pharmaceutical tablets of low concentration (0-5%, w/w), using Fourier Transform Near Infrared (FT-NIR) transmission spectroscopy. The quantitation and detection limits decreased as the upper concentration level of the calibration models was reduced. The results obtained show that the selection of concentration ranges is a critical aspect during model design. The selection of wide concentration ranges with high levels is not recommended for the determination of analytes at minor levels (<1%, w/w), even when the concentration of interest is within the range of the model.