Biomimetic silica xerogel regulates indometacin release and oral bioavailability by virtue of chiral pores

Abstract

Abstract Chiral materials exert special functions to be studied. To explore the chiral porous drug delivery effect of silica xerogel that synthesized using biomimetic method, two carriers with different chirality (BSX-CL and BSX-CD) were prepared. Morphology and porous size distribution of BSX-CL and BSX-CD were characterized. After loading indometacin into the two carriers, systemic physical state was studied using fourier transform infrared spectroscopy (FTIR) and differential scanning calorimeter (DSC) before measuring in vitro dissolution and in vivo pharmacodynamics. The results showed that BSX-CL was small sphere nanoparticles while BSX-CD turned out to be solid interlaced networks. Their distinguished morphology differences were mainly attributed to the function of small chiral molecules, resulting in the relative large mesopores of BSX-CL highly centralized within 5–10 nm, while that of BSX-CD mainly gathered within 6–13 nm. Indometacin was amorphous state in the two carriers, leading to the enhancement of in vitro drug dissolution and oral bioavailability. The relative bioavailability of indometacin loaded BSX-CL and indometacin loaded BSX-CD achieved 1.27 times and 1.87 times higher than indometacin. To summarize, BSX-CL and BSX-CD regulated indometacin release and oral bioavailability via controlling the porous size distribution.