Chitosan-coated boronic acid modified magnetic alginate microbeads: dual encapsulation and release of 5-fluorouracil and resveratrol

In this study, it was aimed to develop magnetic microbeads for dual delivery of 5-Fluorouracil (5-FU) and Resveratrol (RES). Fe₃O₄ nanoparticles were coated with alginate, modified with 3-aminophenylboronic acid (APBA) by carbodiimide chemistry, gelled with CaCl₂, and coated with chitosan after drug loading by swelling method. FTIR, TEM, SEM, ESR, and XRD were used for characterization. Microbeads were further investigated for entrapment efficiency (EE), swelling analysis, <i>in vitro</i> release, and cytotoxicity. Entrapment efficiencies were 62.2 ± 0.78 and 27.1 ± 0.98% w/w for 5-FU and RES, respectively. Drug release was studied at pH 1.5, 5.5, 6.8, and 7.4. Microbeads exhibited the highest release at pH 6.8 (65.3 ± 2.50% w/w for 5-FU and 45.4 ± 1.80% w/w for RES). Release kinetics conformed to Higuchi model at pH 6.8 and Korsmeyer-Peppas at pHs 5.5 and 7.4. Microbeads containing 300 µg/mL drug reduced cell viability of HT-29 colon cancer cell line below 50% in cytotoxicity experiments.