Investi̇gati̇on of surface modi̇fi̇ed hydroxyapati̇tes as drug delivery system

In this study, acetylsalicylic acid adsorption/desorption capacities of surface modified biocompatible HAPs using different templates (cetrimonium bromide, Pluronic®️ P123, Pluronic®️ F127) were investigated and the most suitable surface material as drug carrier was determined. After determining the appropriate synthesis conditions, the surfaces of the HAP materials prepared are CTAB, Polyethylene glycol (PEG), Sodium dodecyl sulfate (SDS), Triton X-100 (TX-100), (3-Aminopropyl) Triethoxysilane (APTES), (3-Aminopropyl) Trimethoxysilane (APTMS) and (3- Mercaptopropyl) Trimethoxysilane (MPTMS) using different surfactants. The prepared HAP materials were loaded with acetylsalicylic acid (ASA) and the controlled releases of the ASA loaded materials in phosphate buffer solution (PBS, pH=7.4) and simulated gastric juice (SMS, pH=1.2) were investigated. The synthesized HAPs were characterized by X-ray diffraction diffractometry (XRD), Fourier transform infrared spectroscopy (FT-IR), Thermogravimetric analysis (TGA), Brunauer, Emmett and Teller (BET) and Scanning electron microscope (SEM) analyses. Although it was observed that all prepared HAPs were a suitable carrier material for ASA adsorption and release, it was determined that HAP prepared with cetrimonium bromide (CTAB) had the highest ASA loading capacity and the synthesis conditions of this material were investigated at different temperatures, time and CTAB amount. In addition, adsorption kinetics, adsorption isotherms and thermodynamics were investigated with different models, and the release mechanism was determined using the Korsmeyer-Peppas equation.