A One-Step Green Microwell Spectrophotometric Assay for the Determination of Certain New Chemotherapeutic Drug Formulations

Background: The formation of charge-transfer complexes (CTCs) of iodine with five chemotherapeutic drugs used for the treatment of different types of cancer has not been investigated. These drugs are olaparib, seliciclib, vandetanib, dasatinib, and tozasertib. Additionally, these drugs need an appropriate general spectrophotometric assay for their analysis in the dosage forms regardless of the differences in their chemical structures. Objective: The aim of this study was the development of a novel microwell spectrophotometric assay (MW-SPA) for one-step determination of these drugs via their interactions with iodine, which resulted in instantaneous production of bright lemon-yellow CTCs. Methods: A spectrophotometric study of the CTCs was conducted, and all CTCs were characterized. Site(s) of interaction on each drug were assigned, and the MW-SPA was developed and applied to the analysis of dosage forms. Results: The findings confirmed that the reactions proceeded via CTC formation. Beer's law was obeyed over a general concentration range of 1-6 mu g/mL. The LODs and LOQs were in the ranges of 0.5-2.1 and 1.5-6.4 mu g/mL, respectively. The proposed MW-SPA demonstrated excellent precisions as the relative standard deviations were < 2.24 and 2.23% for the intra- and inter-assay precision, respectively. Recovery studies demonstrated the accuracy of MW-SPA. Successful determination of all drugs in bulk and tablet forms was achieved using the MW-SPA. The environmental sustainability of the proposed methodology was determined, providing evidence of the assay's alignment with the basis of green analytical chemistry. The high throughput of the assay was documented. Conclusion: In contrast to other existing methods, the MW-SPA described herein was valid for analyzing all drugs at the same wavelength. Highlights: The assay is useful for routine analysis of drugs in their formulations in QC laboratories.