Release of folic acid in mesoporous NFM-1 silica

Mesoporous NFM-1 silica with folic acid as template was prepared taking advantage of the supramolecular self-assembly of pterin groups and their abilities to form hexagonal liquid crystal phases. NFM-1 materials with the varied morphologies such as fiber, chiral twisting long-rod, gyroid, and amorphous particles were prepared by varying the amount of the co-structure directing agent, stirring speed and changing pH value of the synthesis. The release kinetics of NFM-1 samples with different morphologies were studied in phosphate buffer with pH = 7.4 in 37 °C under stirring. All the release kinetic curves are fitted by the power law and Higuchi equations. The fitting of the power law equation was separately done as for the released amount up to 60% or 100%. The materials show slow, long-term and sustained release of folic acid from mesoporous NFM-1 silica, which establishes a new foundation for the potential application in drug delivery and bioimaging.