Abstract
beta-cyclodextrin/diatomite composite (beta-C/D) was characterized as a potential carrier for the ibuprofen drug (IBU) with enhanced loading and release properties. The beta-C/D carrier achieved experimental and theoretical loading capacities of 419 mg/g and 596 mg/g, respectively. The loading behavior follows the Langmuir equilibrium properties and the Pseudo-Second order kinetics. The loaded IBU molecules are of monolayer and homogeneous form and their loading processes involved physical and chemical mechanisms with dominant effect for the physical processes considering the Gaussian energy of value (6.96 KJ/mol). Based on the free energy (-16.9 to -17.4 KJ/mol) and enthalpy (-8.4 KJ/mol), the loading of IBU into beta-C/D occurred by spontaneous, exothermic, and favorable reactions. The release profile of the IBU-loaded beta-C/D extended for 200 h in the gastric fluid (95.4%) and 100 h in the intestinal fluid (100%). The IBU release rate can be controlled by adjusting the ratio of the incorporated beta-cyclodextrin polymer in the composite. The release kinetic studies and the diffusion exponent values of the Korsmeyer-Peppas (0.62 (pH 1.2) and 0.58 (pH 7.4)) suggested release mechanism controlled diffusion as well as erosion processes but with essential effect for the diffusion of the drug. The cytotoxicity studies demonstrate safe and biocompatible effects for beta-C/D and IBU-loaded beta-C/D on human bronchial epithelial cells. The submitted graphical abstract reflect the formation mechanism of beta-cyclodextrin/diatomite and the loading mechanism of ibuprofen drug into its structure.