Electrochemical behavior and voltammetric determination of tryptophan based on 4-aminobenzoic acid polymer film modified glassy carbon electrode.
Herein, a novel electrochemical method was developed for the determination of tryptophan based on the poly(4-aminobenzoic acid) film modified glassy carbon electrode (GCE). The electrochemical behaviors of tryptophan at the modified electrode were investigated. It was found that the oxidation peak current of tryptophan at the modified GCE was greatly improved compared with that at the bare GCE. The effects of supporting electrolyte, pH value, scan rate, accumulation potential and time were examined. The oxidation peak current of tryptophan was proportional to its concentration over the range from 1.0 x 10(-6) to 1.0 x 10(-4)mol L(-1). The limit of detection was evaluated to be 2.0 x 10(-7)mol L(-1). The proposed method was sensitive and simple. It was successfully employed to determine tryptophan in pharmaceutical samples.
Huang
Ke-Jing
KJ
College of Chemistry and Chemical Engineering, Xinyang Normal University, Xinyang 464000, China. kejinghuang@163.com
Xu
Chun-Xuan
CX
Xie
Wan-Zhen
WZ
Wang
Wei
W
D010129:4-Aminobenzoic Acid / Q000737:chemistry*; D002021:Buffers; D002138:Calibration; D002244:Carbon / Q000737:chemistry*; D055664:Electrochemical Techniques; D004563:Electrochemistry; D004566:Electrodes; D004573:Electrolytes; D005898:Glass / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D010084:Oxidation-Reduction; D004364:Pharmaceutical Preparations / Q000737:chemistry; D011108:Polymers / Q000737:chemistry*; D013997:Time Factors; D014364:Tryptophan / Q000032:analysis*
D002021:Buffers; D004573:Electrolytes; D004364:Pharmaceutical Preparations; D011108:Polymers; D002244:Carbon; D014364:Tryptophan; D010129:4-Aminobenzoic Acid