▎ 摘　　要

This paper described a novel, facile and nonenzymatic electrochemical biosensor to detect hydrogen peroxide (H2O2). The sensor was fabricated based on Pd-Pt nanocages and SnO2/graphene nanosheets modified electrode (PdPt NCs@SGN/GCE). The electrochemical behavior of PdPt NCs@SGN/GCE exhibited excellent catalytic activity toward H2O2 with fast response, high selectivity, superior sensitivity, low detection limit of 0.3 mu M and large linear range from 1 mM to 300 mu M. Under these obvious advantages, the constructed biosensor provided to be reliable for determination of H2O2 secreted from human cervical cancer cells (Hela cells). Hence, the proposed biosensor is a promising candidate for detection of H2O2 in situ released from living cells in clinical diagnostics. (C) 2018 Elsevier B.V. All rights reserved.