Fourier-based chemometric resolution of the FOLFOX regimen through digital filtering with poly-metric sustainability assessment

The FOLFOX regimen, comprising oxaliplatin (OXA), 5-fluorouracil (5-FU), and leucovorin (LU), is a standard first-line protocol for colorectal cancer therapy. Given its clinical centrality, developing rapid and high-throughput analytical tools for simultaneous determination of its components is essential. However, severe spectral overlap among the three drugs severely complicates their direct spectrophotometric analysis. In this study, novel spectrophotometric methods were developed and validated for the concurrent quantification of OXA, 5-FU, and LU without preliminary separation steps. While direct and first-derivative spectrophotometric analysis successfully resolved binary fractions, complete resolution of the ternary mixture was uniquely achieved through a hybrid double divisor ratio spectra (HDDR) approach integrating trigonometric Fourier functions. The methods were validated in accordance with ICH Q2(R1) guidelines, exhibiting high linearity (r > 0.999), excellent recoveries (98.0-102.0%), and high precision (RSD < 2.0%) across therapeutic concentration ranges. Furthermore, multi-metric evaluation tools demonstrated improved scores relative to reported chromatographic methods, including higher AES, AGREE, MoGAPI, AGSA, CaFRI, RGB, BAGI, and VIGI scores. The developed HDDR method offers an eco-friendly, rapid, and cost-effective alternative for routine quality control of the FOLFOX regimen.