Fabrication of dendrite PtPd bimetallic nanocomposites modified carbon fiber microelectrodes for detecting superoxide anion released from living cells

In this work, the carbon fiber microelectrode (CFME) coated by ERGO-CNT network was used as a substrate to support dendrite PtPd nanoclusters. An enzyme-free O 2 − electrochemical sensor (PtPd@ERGO-CNT-CFME) was prepared based on this strategy. Due to the brilliant loading and dispersing abilities of the substrate and the excellent electrochemical activity of the dendrite PtPd alloy, PtPd@ERGO-CNT-CFME demonstrated outstanding detection ability towards O 2 − . The as-constructed sensor showed a wide-linear range of 16–744 μM and 744–3064 μM with high sensitivity of 6967.3 μA mM −1 cm −2 and 4124.3 μA mM −1 cm −2 , and the detection limit was 5.07 μM. Furthermore, PtPd@ERGO-CNT-CFME was successfully applied to monitor O 2 − released from living cells. This phenomenon indicated the application potential for O 2 − detection in biological samples.