Enzyme-polymer-single walled carbon nanotube composites as biocatalytic films

Enzyme-containing polymer-single walled carbon nanotube (SWNT) composites have been explored as unique biocatalytic materials. The biocatalytic composites were prepared by suspending SWNT and alpha-chymotrypsin (CT) directly into a poly(methyl methacrylate) solution in toluene. The activity of the resulting CT-polymer-nanotube films was observed to be higher than both polymer-CT and polymer-graphite-CT films. The effect of SWNT loading on biocatalytic activity was also studied, and the optimal SWNT loading was used to compare the biocatalytic performance of different polymer-SWNT systems. In all polymers tested, SWNT-containing composites show higher enzyme activity than the non-SWNT preparations. This was most likely due to a reduction in the leaching of enzyme from the film in the former, perhaps caused by the adsorption of enzyme molecules onto highly structured and high energy SWNTs within the polymer matrix. Investigation of different polymer composites indicates that SWNTs may be used to improve the performance of a wide range of biocatalytic composites for applications ranging from antifouling surface coatings to sensor elements.