Drug delivery and in vitro biological effects of gum ghatti-modified hydroxyapatite nanoporous composites

Abstract

The present study investigates the influence of gum ghatti (GG) concentration on the porosity of hydroxyapatite (HAP), where the final composite has been tested for the effects of drug delivery, antibacterial activity, and in vitro cytotoxicity. Following the synthesis of GG-HAP composite by a simple chemical precipitation method, the various analyses were employed to understand the crystallinity, morphology, chemical composition, surface functionality and internal bonding, etc. From the comparison of physical properties among the sintered and un-sintered GG-HAP composites and that too with different concentrations of GG (1%, 5%, and 10%), we observed the superior properties for the samples formed from higher GG concentration (10%) with sintering. We observed the lowest crystal size of 30 nm with 95% crystallinity, a surface area of 108 m2/g, a total pore volume of 0.2 mL/g, an average pore diameter of 33 Å for the Sin-10% GG-HAP composite. In addition, the biocompatibility test performed on the Sin-GG-HAP pellet confirmed the in-built bioactivity and biostability of the composites in simulated body fluid. Further, the Naringenin drug delivery profiles confirmed for the stable and controlled release of loaded drug from the Sin-GG-HAP composites (with 1, 5, and 10% of GG). We observed the highest release of 96% from the Sin-10% GG-HAP matrix in just 90 min and T50% of 416 h, and a mean diffusion time period of 459 h. Finally, the antimicrobial (using both gram-positive and gram-negative bacteria) and cytotoxic activities (with the use of healthy normal and diseased cells) of the drug-loaded and un-loaded GG-HAP composites confirm the potential role of the formed Sin-10% GG-HAP composite towards biomedical applications.