Corrigendum to "Novel approach for infrared spectroscopic quantitation of azithromycin in commercial tablets employing paracetamol as matrix modifier" [Heliyon 9 (3) (March 2023) Article e14647].

[This corrects the article DOI: 10.1016/j.heliyon.2023.e14647.].

Novel approach for infrared spectroscopic quantitation of azithromycin in commercial tablets employing paracetamol as matrix modifier.

The ATR-FTIR quantitation of azithromycin in three products of commercial tablets was carried out on product specific quantitative regression models using powdered paracetamol as matrix modifier to overcome the variation of spectral response and influence of sample matrix. For each product, a PLS quantitative regression model was established using training infrared spectra obtained from reference mixtures (reference powders with known mass content (%, w/w) of azithromycin mixed homogenously with paracetamol to have mass percentage of azithromycin over total mass of azithromycin and paracetamol (PA) from 30% to 70%). The spectral data were collected in wavenumber range depending on commercial product within the wavenumber zone from 1300 cm-1 to 1750 cm-1 to build quantitative regression models. To quantify azithromycin in any commercial batch of the same product, the homogenized sample powder was mixed with paracetamol to have mixtures with PA value about 50% to record infrared spectrum. The actual amount of azithromycin would then be calculated from spectral response of unknown sample and the pre-established quantitative regression model. Each quantitative regression model was validated according to the current requirements of ICH guideline Q2R1 and those of AOAC International in term of specificity, accuracy, precision, long-term robustness and reliability. The validation results proved that the quantitative regression models were accurate, precise, reliable and robust, able to provide quantitative results of azithromycin in tablets equivalent to those provided by official HPLC method of USP44.

Development and Validation of a Simple, Green Infrared Spectroscopic Method for Quantitation of Sildenafil Citrate in Siloflam Tablets of Unknown Manufacturing Formula.

A simple, easy-to-implement, and green infrared spectroscopic method was developed and validated for the quantitative determination of sildenafil citrate in tablets of unknown manufacturing formula. Homogenized tablet powder with known mass content (%, m/m) of sildenafil citrate was mixed with paracetamol to form standard mixtures with different percentages of sildenafil citrate on the total quantity of sildenafil citrate and paracetamol (designated as R). Unknown tablet samples were finely ground and mixed with paracetamol to form test mixtures having R values about 50%. Infrared spectra of standard mixtures, measured in attenuated total reflectance mode, in the wavenumber zone from 1800 cm-1 to 1300 cm-1 were selected and processed by partial least square regression to form the calibration model for quantitation of sildenafil citrate in unknown samples. Spectral responses of test mixtures and the calibration model were used to determine the exact mass content (%, m/m) of sildenafil citrate in the powder of unknown tablet samples. The method was fully validated in terms of linearity, precision, and accuracy according to the requirements of current guidelines and was proved as reliable and suitable for the intended application.