Cytocompatibility of Caffeic Acid-Silica Hybrid Materials on NIH-3T3 Fibroblast Cells

The hydroxycinnamoyl compound caffeic acid (CA), broadly occurring in plants, is receiving special attention in materials science thanks to its antioxidant, anti-inflammatory, and antimicrobial activities that make it promising for application use in various sectors. In this context, CA–based peptide biomaterials are recently developed as eco-friendly and multifunctional free radical scavengers useable in a wide range of consumer manufacture, ranging from cosmetics to household products, as well as clinical applications, including imaging, drug delivery, and disinfection. Furthermore, a water-soluble chitosan-caffeic acid conjugate, effective in delaying lipid oxidation, is also synthetized. Herein, exploiting sol-gel route versatility, CA/silica materials are synthetized. Hybrids, chemically characterized mainly through spectroscopic techniques, varied in their relative CA content, which represented 5%, 10%, 15%, or 20% of materials’ weight. The synthetized materials are able to elicit anti-radical properties. The CA amount appeared to be determinant in anti-radical activity, as well as in biocompatibility assessment. To this latter purpose, mouse embryonic fibroblast cell line NIH-3T3 cells are utilized and directly exposed to hybrid materials. Redox mitochondrial activity is evaluated by means of the MTT test, whose results are in accordance with the materials’ biocompatibility