Abstract
Layered zinc hydroxide (LZH) nanoparticles are versatile material used for intercalating bioactive and therapeutic molecules with the purpose of obtaining controlled release properties, enhancing their poor aqueous solubility and protecting them from degradation. Co-precipitation method was employed here to synthesis LZH and ion-exchange intercalation of the anti-inflammatory drug mefenamic acid (MA) to prepare MA–LZH nanohybrids. An increase in the basal spacing of the (200) plane from 9.57 Å in pristine LZH to 17.73 Å in the MA–LZH nanohybrid indicated successful intercalation of anionic MA into a LZH gallery, which was arranged in a monolayer fashion with the carboxylate group pointing toward the LZH inorganic interlayers. Fourier-transform infrared spectroscopy confirmed successful intercalation without major changes in the structure of MA. Thermogravimetric analysis results showed that MA is stabilized in the interlayers through electrostatic interaction of MA within the interlayer space of LZH. The drug released from the nanohybrid revealed a controlled profile of about 66% of MA anions released at pH 7.4, while 86% release took place after 14 h at pH 4.8. The mechanism of drug release was explained by the Korsmeyer–Peppas kinetic models. The kinetic studies suggest that drug release mechanism is predominantly diffusion-controlled. In vitro tests performed with normal fibroblast cells indicated synergistic anti-inflammatory performance compared to pristine LZH and pure MA; hence, MA–LZH nanohybrid effectively affected controlled-release performance. Because of ease of preparation and sustained release of the active and less-toxic compounds to the cell, this nanohybrid could be regarded as a potential drug delivery system