Mesoporous synthetic hectorites: A versatile layered host with drug delivery application

The efficacy of mesoporous synthetic hectorites (MSH) as drug delivery carrier was examined. Mesoporous synthetic hectorites have been synthesized (both with and without organic template) by hydrothermal crystallization of gels containing silica, magnesium hydroxide, lithium fluoride, and an organic template. 1,3-didecyl-2-methylimidazolium chloride (DDMI) was used as pore directing agent. The nanocomposites involving quinine (QUI), an antimalarial drug adsorbed onto mesoporous synthetic hectorites were assembled. The nanocomposites were characterized by X-ray diffraction (XRD), surface area, Fourier transform infrared spectroscopy (FT-IR), and thermal analysis techniques. The decrease in the surface area and pore volume after drug adsorption suggested the adsorption of drug in the mesopores. The synthesized MSH–QUI nanocomposites were coated with sodium alginate (AL) via gelation technique. The in vitro drug release rate of the nanocomposites was monitored in the sequential buffer environments at 37 ± 0.5 °C. The drug release profile was dependent upon the pore size of the MSH. The drug release rate in the gastric environments was controlled by alginate coating. Different dissolution–diffusion kinetic models were applied to study the release kinetics of QUI from the carriers, and it was found that this process can be described by the Elovich equation.

In a typical synthesis of MSH, the sol–gel is hydrothermally treated to crystallize an organic–clay composite. The structure directing agent is then removed by calcinations, generating an inorganic network with a narrow distribution of pores in the mesoporous range. Antimalarial drug quinine was adsorbed in the formed mesopore.Figure optionsDownload as PowerPoint slideResearch highlights
► Mesoporous synthetic hectorites were synthesized (both with and without organic template) by hydrothermal crystallization.
► The nanocomposites involving quinine, an antimalarial drug adsorbed onto mesoporous synthetic hectorites were assembled.
► The in vitro drug release rate of the nanocomposites were monitored in the sequential buffer environments at 37 ± 0.5 °C, and it was dependent upon the pore size of the mesoporous synthetic hectorites.