Mesopourous Fe ₃ O ₄@SiO ₂-hydroxyapatite nanocomposite: Green sonochemical synthesis using strawberry fruit extract as a capping agent, characterization and their application in sulfasalazine delivery and cytotoxicity

The present study introduces a simple, biocompatible and effective drug delivery system by using mesoporous nanocomposite-based platform. To achieve this goal, mesopourous Fe₃O₄@SiO₂-hydroxyapatite nanocomposite (mFSH) was synthesized by sonochemical process in presence of strawberry fruit extract as capping agent (mFSH-SW). The impact of various factors such as sonication time (5, 15, 30 and 45 min), capping agent (cherry (CH), strawberry (SW), malus domestica (MD), andean blackberry (AB)), pH (10, 11 and 12) and sonication power (30, 60 and 80 W) were investigated to reach optimum condition. To reach high efficiency of drug loading, mFSH was grafted with 3-aminopropyl triethoxysilane (APTES). Uniform, regular and spherical morphology of nanocomposite were specified by field emission scanning electron microscopy (FESEM), X-ray powder diffraction (XRD), vibrating sample magnetometer (VSM), high-resolution transmission electron microscopy (HRTEM), energy-dispersive x-ray spectroscopy (EDX), dynamic light scattering (DLS), nitrogen adsorption/desorption isotherm and Fourier-transform infrared spectroscopy (FT-IR) techniques. The mean pore size, surface area, and pore volume of mFSH-SW were 63.2 m² g^-1, 14.1 nm and 0.24 cm³ g^-1, respectively. Sulfasalazine (SLN) loading and release were carried out by various products. The functionalized mFSH-SW showed high adsorption capacity (approximately 59.1 %) for SLN that possesses amino functional groups. The results showed that 100 % of SLN-loaded nanocomposite could be released after 36 h at intestinal conditions (pH = 6.8). In addition, in-vitro and in-vivo toxicity investigations of product were performed with apoptosis/necrosis, XTT and pathology assay, respectively. All in all, unique properties of the nanocomposite including low toxicity, high drug loading, slow release and biodegradable showed that it can be used in biomedical sciences.

Keywords: Hydroxyapatite; Magnetic carrier; Nanocomposite; Sonochemistry; Sulfasalazine delivery; XTT.