Greenness appraisal and development of validated spectrophotometric methods for assay of amprolium: Comparative study using Analytical Eco-Scale, GAPI, and AGREEmetric approaches

•Amprolium hydrochloride is a main drug used for treatment of Intestinal coccidiosis in poultry.•Development of three green spectrophotometric methods for assay of Amprolium in dosage form.•Greenness assessment comparison between proposed and reported methods via AES, GAPI and AGREE approaches.•The developed methods are advantageous for QC laboratories regarding simplicity, economy, and greenness. Intestinal coccidiosis is a serious parasitic disease in poultry. Amprolium hydrochloride(AMP) is widely used for the treatment and prevention of coccidiosis. Three simple and green spectrophotometric methods have been developed for assay of AMP in bulk powder and in dosage form. The first method relies on measuring the first derivative (D1) spectrum at Δλ= 3 nm of AMP. This D1 spectrum possesses a characteristic peak at 234 nm. The second method relies on measuring the difference spectrophotometry (ΔA) and its first derivative (ΔD1) spectra of the drug solutions in 0.1 N HCl against the corresponding solutions in 0.1 N NaOH. The value of amplitudes of ΔA and ΔD1 (∆λ = 3 nm) were measured at 248 and 240 nm, respectively. The third method involves a colorimetric reaction with KMnO4 in alkaline medium and measuring the colored product at 610 nm. The developed methods were validated in accordance with ICH guidelines and evaluated for greenness using three greenness metrics; Analytical Eco-Scale (AES), Analytical GREEness calculator (AGREE), and Green Analytical Procedure Index (GAPI). All proposed methods showed excellent simplicity as they don't require sophisticated instrumentation or tedious analytical procedure steps.