Europium Oxide Nanocomposite Carbon Paste Electrode for Determination of Tyrosine Using FFT Continuous Cyclic Voltammetry in a Flow Injection System

A novel method for determination of tyrosine in flow-injection systems has been developed. A europium oxide nanocomposite carbon paste electrode was used to improve the sensitivity of the electrode response. Signal to noise ratio has significantly increased by application of discrete FFT method, background subtraction and current-time integration of the electrode response over a selected potential range. The effects of various parameters on the sensitivity of the method studied. The best response was obtained in pH=7.0, potential scan rate=1 Vs-1, accumulation time=0.5s, and accumulation potential=-500 mV. Detection limit was 6.6×10-9 mol L-1 of tyrosine. The technique has good accuracy and high sensitivity.