Background: The development of nanomaterials modified electrode can provide more opportunities
for the enhancement of the analytical performance in constructing electrochemical sensor
and biosensor. LiFePO4 (LFP) is a promising candidate to develop new modified electrodes owing to its
advantages such as cheap cost, environmental compatibility, high safety, non-toxicity, large theoretical
capacity, long cycle life and abundant earth materials.
Objective: The aim of this paper was to construct nanosized LFP modified electrodes, which could be
applied as working electrode for rutin analysis and as an electrochemical biosensor for direct electrochemistry
of Hemoglobin (Hb).
Method: Nanosized LFP was characterized by scanning electron microscopy. The LFP modified electrodes
with Carbon Ionic Liquid Electrode (CILE) as substrate electrode were fabricated by dropping
method with chitosan (CTS) as film. Cyclic voltammetry and electrochemical impedance spectroscopy
were carried out to examine the electrochemical performance of the modified electrodes. Differential
pulse voltammetry was used to establish determination methods.
Results: Two new LFP-based modified electrodes (CTS/LFP/CILE and CTS/Hb-LFP/CILE) were fabricated.
The electrochemical behaviors of rutin on CTS/LFP/CILE were achieved with a pair of enhanced
redox peaks. The linear range for rutin analysis was from 4.0×10-8 to 1.0×10-4 mol L-1 with a
detection limit of 8.0×10-9 mol L-1. The direct electrochemistry of Hb in CTS/Hb-LFP/CILE was realized
with a pair of obvious redox peaks. The electrocatalytic activity of CTS/Hb-LFP/CILE toward
trichloroacetic acid and H2O2 reduction were investigated, and the detection limits of 0.068 mmol L-1
for TCA and 0.07 µmol L-1 for H2O2 were obtained.
Conclusion: Two kinds of LFP modified electrodes were successfully constructed with improved electrochemical
performances. Electrochemistry of rutin and Hb were realized on LFP based electrodes
with enhanced responses, and the application of LFP nanoparticle in electrochemical sensor and biosensors