Morphology of genipin-crosslinked BSA networks yields a measurable effect on the controlled release of vitamin B6

Abstract

We examined the morphology of a network made with native BSA molecules being crosslinked with genipin at ambient temperature. Ninhydrin assay, FTIR, WAXD, SEM and mechanical tests documented successful crosslinking that enhanced the structural properties of the three dimensional structure. Its hydrophilic nature allows swelling with water absorption, which can be monitored with the modified Flory-Rehner theory to predict the molecular weight between adjacent crosslinks, network mesh size and crosslinking density as a function of crosslinker addition. Characterisation studies were carried out with a view to developing a delivery vehicle for the controlled release of vitamin B6 over a prolonged period of observation. Moving boundaries associated with swelling of the protein matrix resulted in vitamin transport that could be described with the interplay of diffusional and relaxational kinetics via the Peppas-Sahlin equation. Combination of diffusion and swelling equilibrium theories unveils a measurable effect of network characteristics on vitamin B6 release.