Validated Analytical Approaches for Sitagliptin Monohydrate and Metformin: A Critical Review

The two main treatments for type 2 diabetes mellitus are sitagliptin and metformin, which are frequently taken together to provide the best possible glycemic control. The objective of this review is to critically assess analytical and bioanalytical methods for measuring metformin and sitagliptin, either separately or together, in biological matrices and pharmaceutical formulations between 2005 and 2025. Titrimetric analysis, spectrophotometry, chromatography (high-performance and ultra-performance liquid chromatography), electroanalytical methods, capillary electrophoresis, and chemometric approaches are among the techniques evaluated. While spectrophotometry delivers routine analysis at a reasonable cost, chromatography offers excellent sensitivity and resilience, making it perfect for complicated matrices. Chemometric techniques improve data interpretation, whereas capillary electrophoresis and electroanalytical techniques guarantee accuracy for particular applications. Each method's validation metrics, including specificity, accuracy, and reproducibility, were examined. Applications include therapeutic monitoring, pharmacokinetic research, and quality control. High equipment expenditures for sophisticated methods and matrix interference in biological samples are among the drawbacks. Method procedures are made clearer by schematic workflows, which also help choose techniques according to matrix complexity, cost, and sensitivity. According to this review, the choice of method is contingent upon the analytical requirements; chromatography is a diverse but resource-intensive technique, while spectrophotometry and other simpler methods are better suited for everyday work. These observations help researchers optimize metformin and sitagliptin measurement techniques, promoting improvements in diabetes care.