Green spectrophotometric strategies for the estimation of ivermectin and rafoxanide in veterinary formulation

Abstract Development and validation of simple, accurate, precise, selective, and sensitive UV spectrophotometric methods for the determination of Ivermectin (IVM) and Rafoxanide (RFX) in pure and dosage forms without any interference. The applied spectrophotometric methods are: zero-order absorption spectra (D 0 ), third-derivative spectrophotometry (D 3 ), dual wavelength in ratio spectra (DWRS), bivariate (BV), and mean centering of ratio spectra (MCR). The proposed methods are applied using either zero/or derivative/or ratio spectra and mathematical techniques. To the best of our knowledge, this is the first report describing the simultaneous spectrophotometric determination of IVM and RFX using derivative and chemometric-assisted UV spectrophotometric methods. The methods are based on absorbance measurements of the binary mixture using methanol as solvent. The linearity ranges were measured to be 2–60 and 3–40 µg/mL for IVM and RFX, respectively. Low LOD range with high sensitivity was 0.490–0.888 and 0.321–0.668 for IVM and RFX, respectively. These methods were evaluated according to ICH guidelines. The satisfactory results indicate that the proposed methods can be used for quality control evaluation of IVM and RFX in their dosage form, overcoming some challenges like spectral overlap. Statistical comparison of the suggested spectrophotometric methods with the reported HPLC method inferred no significant difference between them. Greenness of the proposed spectrophotometric methods was evaluated using Analytical GREEnness Metric (Agree) with good score (0.71), Modified Green Analytical Procedure Index (MoGAPI) with an excellent score (84.0), and Analytical Greenness Star Area (AGSA) that its score equal (80.56). While the practicality and whiteness were evaluated using the Blue Applicability Grade Index (BAGI) showing a score of (80.0) and RGB12 with score (96.0), respectively. The high scores obtained reflect a synergistic harmony between these dimensions. This indicates that the proposed spectrophotometric methods are not only more environmentally benign but also analytically robust and practically viable.