Self-powered triboelectric aptasensor for label-free highly specific thrombin detection

An aptamer-based triboelectric biosensor is developed for a highly specific, label-free and self-powered detection of thrombin. For the first time, intermolecular recognition interactions are used to develop a selective nanosensor based on triboelectric effect. Positively charged Au nanoparticles (Au NPs⁺) with large difference in triboelectric polarity and work function are assembled onto Al film to increase the electrical output of triboelectric nanogenerators (TENG). Modification of anti-thrombin aptamers on the Au NPs⁺-assembled TENG affords the triboelectric nanosensor highly selective toward thrombin, even in clinical samples because of specific binding affinity between aptamers and thrombin unlike random DNA-modified TENGs with undetectable response. A 0.41 nM limit of detection is achieved, which is directly demonstrated by the number of commercial LED lights without any supporting equipment such as power source and electrometer. Our study demonstrates an innovative and unique approach toward the self-powered and label-free detection of thrombin for rapid and simple in-field analysis.