TiO2 and shrink induced tunable nano self-assembled graphene composites for label free biosensors

This paper presents a simple and low cost fabrication method to derive tunable graphene composites. We used self-assembly technique to deposit graphene nanoplatelets, and used TiO2 nanoparticles and shrink polymer to tune the film. Compared with conventional graphene composites which properties are fixed, this proposed graphene composites are tunable and controllable on its wetting ability (from ultra-hydrophobic to ultra-hydrophilic) and electrical properties, even after synthesis processes. Significant improvement of the performances of biosensors based on the new graphene composites was observed. The heat shrink enhances the output signal of the biosensor, and the sensitivity of the sensor grows with the TiO2 nanoparticles. Biosensor based on the new graphene composites is able to detect different types of lung cancer biomarkers with superb detection limit and specificity.