Ru nanosheets with specific peroxidase activity for biosensor applications

Nanozymes displaying peroxidase-like activity are helpful for various biomedical applications. In this work, uniform triangular Ru nanosheets (NSs) prepared by a facile hydrothermal approach are first found to possess high performance and specific peroxidase (POD)-like activity which catalyzes the oxidation of colorless 3,3’,5,5’-tetramethylbenzidine (TMB) with H2O2 to blue oxidized TMB (oxTMB). On basis of their outstanding POD activity, we successfully developed two highly sensitive colorimetric methods for detections of ethanol (0.02 - 0.88 mM, R2 = 0.9909) and uric acid (UA) (3.91 - 500 μM, R2 = 0.9938) in serum under the optimal conditions. The detection limits were 0.011 mM and 3.05 μM for ethanol and UA, respectively. These Ru NSs-based biosensors possess prominent characteristics of simple operation, sensitivity, reliability and high selectivity, enabling them suitable for on-demand analysis.