Macrocyclic Compounds Based Chemically Modified Electrodes for Voltammetric Determination of L-Tryptophan Using Electrocatalytic Oxidation

Abstract

The electrochemical behavior of L-tryptophan is studied at carbon paste electrode and electrodes modified with different macrocyclic compounds of which Dibenzo-18-crown-6 (DB18C6) showed better response for L-tryptophan at + 0.95 V vs. Ag/AgCl. Use of Ni²⁺ ions as electrocatalyst shows a further enhancement in peak current leading to a linear range of 1.96 × 10⁻⁶ − 1.01 × 10⁻³ M and a detection limit of 9.79 × 10⁻⁸ M by differential pulse voltammetry. Electrochemical impedance diagnosis reveals that L-tryptophan oxidation is kinetically facile on DB18C6 modified electrode. The modified electrode is used for L-tryptophan determination in real samples.

Keywords:

• Chemically modified electrode
• Differential pulse voltammetry
• Eletrocatalysis
• L-tryptophan
• Macrocyclic compounds

The Department of Science and Technology, and Board of Research in Nuclear Sciences, Government of India, are thanked for providing the financial assistance for this work. Also, thanks to Dr. M. Sudersanan for assistance with preparation of the manuscript.

Notes

^a  mg mL⁻¹.

*Source: www.nutritiondata.com.