Electrochemical Determination of 4-Nonylphenol Based on Graphene-Chitosan Modified Glassy Carbon Electrode

A grapheme. chitosan modified glassy carbon electrode (GR-CS/GCE) was prepared by in situ reduction and characterized by Fourier transform. infrared (FT-IR) spectra and Raman spectra. The results showed that the graphene oxide (GO) was successfully deoxygenized. On the basis of this, the electrochemical behavior of 4-nonylphenol (4-NP) was investigated by cyclic voltammetry and differential pulse voltammetry. It was found that the oxidation current at GR-CS/GCE electrode was obviously larger than that at GCE electrode and GO-CS/GCE electrode, and the oxidation potential shifted negatively, indicating that the GR-CS/GCE electrode had obviously catalytic activity on the 4-NP's oxidation. Experimental parameters, such as accumulation potential and time, scan rate, and pH value of buffer solution were optimized. Under the optimized conditions, the oxidation peak current was proportional to 4-NP concentration in the range between 0.01 and 40.0. mol/L, the linear equation was I (mu A) = 0.364C (mu mol/L) + 0.618 (R = 0.9988) and the detection limit was 0.0052 mu mol/L (S/N = 3). Finally, this proposed sensor was successfully employed to determine the 4-NP in real samples and the recoveries were between 95.0% and 101.0%.