Core-shell iron oxide-layered double hydroxide: High electrochemical sensing performance of HO biomarker in live cancer cells with plasma therapeutics.

In this work, we develop a new type of multifunctional core-shell nanomaterial by controllable integration of CuAl layered double hydroxides (LDHs) over the surface of iron oxides (FeO) nanospheres (NSs) to fabricate (FeO@CuAl NSs) hybrid material with interior tunability of LDH phase and explore its practical application in ultrasensitive detection of emerging biomarker, i.e., HO as cancer diagnostic probe. In addition, atmospheric pressure plasmas (APPs) have also been used as potential therapeutic approach for cancer treatment. Due to the synergistic combination of p-type semiconductive channels of LDHs with multi-functional properties, unique morphology and abundant surface active sites, the FeO@CuAl NSs modified electrode exhibited attractive electrocatalytic activity towards HO reduction. Under the optimized conditions, the proposed biosensor demonstrated striking electrochemical sensing performances to HO including linear range as broad as 8 orders of magnitude, low real detection limit of 1nM (S/N = 3), high sensitivity, good reproducibility and long-term stability. Arising from the superb efficiency, the electrochemical biosensor has been used for in vitro determination of HO concentrations in human urine and serum samples prior to and following the intake of coffee, and real-time monitoring of HO efflux from different cancer cell lines in normal state and after plasma treatment. We believe that this novel nano-platform of structurally integrated core-shell nanohybrid materials combined with APPs will enhance diagnostic as well as therapeutic window for cancer diseases.