Properties of glutaraldehyde cross-linked vicilin nano- and microparticles

The influence of some selected factors on the properties of nano- and microparticles obtained from vicilin (storage protein from Pisum sativum L.) has been studied. These systems were prepared by coacervation followed by a cross-linking step with glutaraldehyde. Stabilized vicilin particles could be formed very rapidly after a short exposure to a low glutaraldehyde concentration. Nevertheless, particles increased in size with time of reaction and with an increase in glutaraldehyde concentration. On the other hand, the cross-linking process greatly influenced particle stability when incubated in the presence of trypsin. In this case, degradation followed a square-root-time relationship, suggesting enzymatic attack at the surface and in the interior of the matrix. The influence of the particle size on the tryptic degradation was also investigated and led to similar conclusions. Thus, microparticles showed a more rapid degradation than might be anticipated considering particle diameter alone.