The application of Near Infrared Reflectance Spectroscopy (NIRS) for the quantitative analysis of hydrocortisone in primary materials

Near Infrared Reflectance Spectroscopy (NIRS), coupled with fiber optic probes, has been shown to be a quick and reliable analytical tool for quality assurance and quality control in the pharmaceutical industry, both for verifications of raw materials and quantification of the active ingredients in final products. In this paper, a typical pharmaceutical product, hydrocortisone sodium succinate, is used as an example for the application of NIR spectroscopy for quality control. In order to develop an NIRS method with higher precision and accuracy than the official UV/VIS spectroscopic method (BP '99), 19 samples, taken from one year’s production and several prepared in the laboratory, having a hydrocortisone sodium succinate concentration in the range from 89.05 % to 95.83 %, were analysed by NIR and UV/VIS spectroscopy. Three frequency ranges: 5939.73–5627.32 cm-1; 4863.64 – 4574.36 cm-1; 4308.23–4200.24 cm-1, with the best positive correlation between the changes in the spectral and concentration data, were chosen. The validity of the developed NIRS chemometric method for the determination of the hydrocortisone sodium succinate concentration, constructed by the partial least squares (PLS) regression technique, is discussed. A correlation coefficient of 0.9758 and a standard error of cross validation (RMSECV) of 1.06 % were found between the UV/VIS and the NIR spectroscopic results of the hydrocortisone sodium succinate concentration in the samples.