Sol-gel silica based networks with controlled chemical properties

In this work, different chemical functionalities, both organic and inorganic, were inserted in a silica glass based sol-gel derived network to create specific chemical activities. Modified silica glass networks were prepared by reacting alkoxysilanes with different chemical functionalities, such as tetraethoxysilane (TEOS), aminopropyl triethoxysilane (APS) and mercaptopropyl triethoxysilane (MPTS), among others. The obtained gels were evaluated by using infrared spectroscopy, mercury picnometry and electron microscopy. The chemical activity of the created multifunctional surfaces was evaluated by the ability of the incorporated proteins to remain adsorbed onto the different gels. Porcine insulin (PI) and bovine serum albumin (BSA) were impregnated into modified networks and desorption of those proteins was monitored. Results showed that gels with multifunctionalities regularly dispersed can be successfully produced by optimizing some of the processing parameters of the gels, such as pH and concentration of reactants. Results also revealed that the type and concentration of chemical functionalities within the gels regulate the ability of incorporated proteins to remain adsorbed on them, suggesting that chemically patterned surfaces and interfaces can be prepared which regulate protein-substrate interactions. (C) 2000 Elsevier Science B.V. All rights reserved.