High‐Performance and Reversible Bitter Taste Sensing Using Aptamer‐Functionalized Graphene Channel for Real‐Time Electronic Tongue

Dynamic and real-time sensing of taste is increasingly important for food safety and pharmaceutical quality control, yet the development of advanced sensors for each taste, especially those for bitterness, remains limited. The challenge has been lying on developing suitable receptors for bitter compounds that are capable of reversible operation. Here, we present a graphene-based taste sensor that integrates a quinine-specific aptamer, enabling selective molecular recognition with high sensitivity and operational stability. Especially, unlike previous sensors, which were irreversible or required regeneration steps, our design achieves fully reversible quinine-specific capture and release. Combined with previously developed taste sensors by the authors, graphene-based electronic tongue was demonstrated to differentiate four different taste compounds and even complex beverages. This work highlights the strong potential of the graphene-based sensors with aptamer receptors as reliable and tunable platforms for advanced taste sensing and real-time analysis.