Synthesis and characterization of Fe0@chitosan/cellulose biocompatible composites from natural resources as advanced carriers for ibuprofen drug: reaction kinetics and equilibrium

Abstract

Green nanocomposites of Fe⁰@chitosan/cellulose (Fe⁰@CH/CS) were synthesized utilizing a green extract of Khaya senegalensis leaves and sugarcane bagasse as a cellulose precursor. The composite was evaluated as an effective carrier for ibuprofen drug (IBF) considering its release and loading properties. The Fe⁰@CH/CS composite has a significant IBF loading capacity of 553 mg g⁻¹, and the loading behavior can be directed by the values of the experimental variables. The loading of IBF into Fe⁰@CH/CS is in agreement with the classic Langmuir isotherm (R² > 0.95) and pseudo-first-order kinetic (R² > 0.97). This displays homogeneity, physisorption, and monolayer loading of IBF into Fe⁰@CH/CS. Based on the findings of the monolayer model with one energy as an advanced isotherm model, the Fe⁰@CH/CS structure has 252.6 mg g⁻¹ active receptor density and each receptor is occupied by two or three IBF ions (n = 2.18) via a multi-molecular mechanism. The determined IBF loading energy (4.81 kJ mol⁻¹) demonstrates the physical loading of the drug by van der Waals forces and/or hydrogen bonding. The Fe⁰@CH/CS structure has significant release profiles as a carrier for IBF, which continued up to 260 h (gastric buffer) and 180 h (intestinal buffer). The studied release kinetics and the obtained diffusion exponent (0.58 (pH 1.2) and 0.48 (pH 7.4)) reflect the release of IBF from Fe⁰@CH/CS by complex diffusion and erosion mechanisms. The cytotoxicity tests declared the safety and biocompatibility of both Fe⁰@CH/CS and IBF-loaded Fe⁰@CH/CS in human bronchial epithelial cells.