Authors: J. Zhou, Q. Yang, X. Pan, S. Gunasekaran
Affilation: University of Wisconsin Madison, United States
Pages: 398 - 401
Keywords: alphs-lactalbumin, beta-lactoglobulin, carbon nanotube, biosensor, encapsulation
The immobilization of proteins on carbon nanotubes is attracting much attention because the resultant hybrid nanomaterials are potentially useful as biomolecular nanosensors . -lactalbumin and -lactoglobulin are the major proteins in whey, the by-products of cheese making. We immobilized partially hydrolyzed -lactalbumin and -lactoglobulin on multiwalled carbon nanotubes (MWNT) using the 1-pyrenebutuanoic acid succinimidyl ester (PySE) as a connector. First, the PySE was attached to MWNT by the - stacking interaction in dimethylformamide (DMF). Then, -lactalbumin or -lactoglobulin was immobilized on the pre-attached MWNT in an aqueous solution by a reaction between amine group of -lactalbumin or -lactoglobulin and N-hydroxysuccinimide of the PySE. The resultant functionalized MWNT was systematically characterized by TEM, SEM, UV, XRD, TGA and FTIR. Results show that the functionalized MWNT has an obvious shell-core structure and was quite soluble in aqueous medium. Thus, the MWNT we have developed has many promising potential applications as food biosensors. The effects of conjugation of carbon nanotubes to protein backbones on their functional properties, such as gelling and emulsifying, were also determined using a dynamic rheometer, texture analyzer, and emulsion characterization. The introduction of carbon nanotube to functional proteins may enhance their encapsulation properties for targeted delivery of bioactive and pharmaceutical compounds.