Determination of sunset yellow in beverage based on solution-gated graphene transistors with multi-walled carbon nanotube functionalized gate electrodes

Abstract

• A sunset yellow sensor based on solution-gated graphene transistor is proposed. • The sensor is modified by multi-walled carbon nanotubes and chitosan. • The sensor has a detection limit as low as 300 nM. • The sensor can be used for sunset yellow content in actual samples. Sunset yellow, one of the most widely used synthetic pigments in the food industry, may cause an adverse reaction in the human body due to its cytotoxicity and potential genotoxicity when overdosed. Developing a rapid, low-cost, and convenient detection method for the sunset yellow pigment is necessary. In this study, we report the fabrication of a highly sensitive and selective sensor for sunset yellow detection based on solution-gated graphene transistors (SGGT). To improve the performance of the SGGT-based sensor, we modified the Au gate electrode with multi-walled carbon nanotubes (MWCNTs). The detection limit of the MWCNT-modified SGGT sensor was 100 nM, and the linear range was from 300 nM to 100 μM. More importantly, the SGGTs sensor showed a selective response to sunset yellow. Finally, we demonstrated that the optimized SGGT-based sensor could detect the concentration of sunset yellow in Fanda soft drink. Therefore, we believe that the SGGT-based sensor with the reported effective modification can be used in the field of food safety and quality control, providing a promising platform for detecting many other analytes.