Chemometric Determination of the Acidity Constant of Etodolac Using PARAFAC and MCR-ALS Modeling of UV-pH Spectral Dataset
CHEMISTRYSELECT, vol.10, no.43, 2025 (SCI-Expanded, Scopus)
- Publication Type: Article / Article
- Volume: 10 Issue: 43
- Publication Date: 2025
- Doi Number: 10.1002/slct.202503407
- Journal Name: CHEMISTRYSELECT
- Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Chemical Abstracts Core
- Keywords: Chemometric pKa determination, Etodolac, MCR-ALS model, PARAFAC model, Spectrophotometry, UV-pH absorbance dataset
- Ankara University Affiliated: Yes
Abstract
The acidity constant (pKa) is a fundamental physicochemical parameter that affects a drug's solubility, permeability, and bioavailability. In this study, chemometric modeling strategies, parallel factor analysis (PARAFAC), and multivariate curve resolution-alternating least squares (MCR-ALS), were applied to UV-pH absorbance data of the nonsteroidal anti-inflammatory drug etodolac. Spectral measurements across varying concentrations and buffer media were modeled to resolve acidic and basic species profiles. The calculated pKa values, 4.64 (PARAFAC) and 4.55 (MCR-ALS), showed strong agreement and confirmed the reliability of these approaches. The results highlight the potential of multiway and bilinear modeling as rapid, titration-free alternatives for precise pKa determination in pharmaceutical analysis.