Systematic study of caffeine content variations and their conversion into controlled-release nanomaterials

This study systematically extracted, quantified, and utilized caffeine from three commercial tea brands (Meena, Ispahani, and Seylon) to compare their stimulant content and develop a novel nanocomposite material. Caffeine was isolated via chloroform-based solvent extraction and quantified using UV–Vis spectrophotometry at 272 nm. Ispahani tea exhibited the highest caffeine yield (4.72%), achieving optimal extraction after 5 minutes and following zero-order kinetics (k = 0.039 M-¹ s-¹, R² = 0.8643). Structural analyses (UV–Vis, FTIR, NMR, MS) confirmed the caffeine's purity and identity. The isolated caffeine was intercalated into a magnesium–aluminum layered double hydroxide (Mg–Al LDH) through urea hydrolysis, as verified by FTIR. This novel caffeine–LDH hybrid shows promise for controlled-release and pharmaceutical applications, while also providing quantitative insights into the caffeine content of local teas. KEY WORDS: Tea, Caffeine extraction, Spectrophotometry, Kinetics, Bioactive compound, Valorisation Bull. Chem. Soc. Ethiop. 2027, 41(1), 119-132. DOI: https://dx.doi.org/10.4314/bcse.v41i1.9