Abstract

Abstract Background Modern built-in spectrophotometer's software supporting mathematical processes was a solution for increasing the selectivity for multicomponent in mixture. Objective Simultaneous spectrophotometric determination of the three naturally occurring antioxidants; rutin, hesperidin, and ascorbic acid in bulk forms and combined pharmaceutical formulation. Methods This was achieved by factorized zero order method (FZM), factorized derivative method (FD1M), and factorized derivative ratio method (FDRM); coupled with spectrum subtraction. Results Mathematical filtration techniques allowed each component to be obtained separately in either its zero, first, or derivative ratio form, thus allowed getting spectra typical to the pure components present in Vitamin C Forte® tablets. The proposed methods were applied over a concentration range of 2–50, 2–30, and 10–100 µg/mL for rutin, hesperidin, and ascorbic acid; respectively. Conclusion Recent methods for the analysis of binary mixtures as FZM and FD1M were successfully applied for the analysis of ternary mixtures and compared to the novel FDRM and all revealed to be specific and sensitive with successful application on their pharmaceutical formulation. Validation parameters were evaluated in accordance with the ICH guidelines. Statistical results were satisfactory revealing no significant difference regarding accuracy and precision. Highlights Factorized methods were able to resolve spectra identical to those of pure drugs present in mixture. Overlapped spectra of ternary mixtures could be resolved by SS-FDRM or by successive application of FZM and FDM.