Physico-chemical characterization of the interaction of red fluorescent protein — DsRed with silica layers

The Discosoma Recombinant Red Fluorescent (DsRed) protein is the latest member of the family of fluorescent proteins. It holds great promise for applications in biotechnology and cell biology. However, before being used for rational engineering, knowledge on the underlying mechanisms relating the DsRed structural stability and adsorption properties on solid surfaces is highly demanded. The physico-chemical analysis performed in this study reveals that the interaction of DsRed with SiO2 surfaces does not lead to protein denaturation. The secondary structure of DsRed is preserved after adsorption and dehydration. The measured contact angles of sessile droplets with different DsRed concentrations determine the interaction as hydrophilic one. The photoluminescence emission of dehydrated DsRed droplets is found to be slightly red-shifted, peaking at 590 nm.