Efficient electrochemical sensor for determination of H2O2 in human serum based on nano iron‑nickel alloy/carbon nanotubes/ionic liquid crystal composite

Abstract A simple and efficient electrochemical sensor is presented for detecting H2O2 in human blood serum based on ionic liquid crystal (ILC), carbon nanotubes (CNTs) and Fe-Ni alloy nanoparticles modified glassy carbon electrode (GC). The sensor is fabricated by drop-casting two successive thin layers of ILC and (CNT-Fe-Ni) mixture over a GC surface; GC/ILC/(CNT-Fe-Ni). The synergism between the composite modifiers leads to excellent electrocatalytic activity toward H2O2 reduction in phosphate buffer solution with a well-identified reduction peak at −380 mV. The H2O2 conversion process is kinetically more favored over the sensor surface with a reduction current value of 178 μA compared to other studied modified electrodes. Amperometry determination of H2O2 in blood serum using the proposed sensor is achieved in a wide concentration range (0.007–1000 μM) and with low detection limit (0.971 nM). Practical application of the GC/ILC/(CNT-Fe-Ni) sensor is effectively assessed in human serum samples with acceptable recoveries, excellent anti-interference ability and long-term stability.