Highly sensitive and selective sulfite sensors based on solution-gated graphene transistors with multi-walled carbon nanotube functionalized gate electrodes

Due to the potential toxicity of sulfite as widely used food additive, there is urgent need for the development of low-cost, rapid and convenient sensors for sulfite detection. Toward this end, highly sensitive and selective sulfite sensors based on solution gated graphene transistors (SGGTs) was innovatively developed. The performance of the device was significantly improved through the functionalization of the gate electrode with multi-walled carbon nanotubes (MWCNTs). We found that the MWCNT modified SGGT sensor showed an ultra-low detection limit of 30 nM toward sulfite. In addition, we also demonstrated that the SGGT-based sulfite sensor was capable of detecting sulfite content in practical liquor samples with high recovery rate. Considering its low-cost and easy-fabricating features, we believe that the SGGT-based sensor with appropriate functionalization may be applied as a highly potential platform for ultra-sensitive detection of a broad range of important analyzes in practical samples for food safety purpose.