Graphene blended with SnO2 and Pd-Pt nanocages for sensitive non-enzymatic electrochemical detection of H2O2 released from living cells.

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 μM and large linear range from 1 μM to 300 μM. 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.