Purpose: The novel sodium dodecyl sulfate modified carbon nanotube paste electrode (SDS/ CNTPE) was used as a sensitive sensor for the electrochemical investigation of L-tyrosine (TY). Methods: The electrochemical analysis of TY was displayed through cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The surface morphology of SDS/CNTPE and bare carbon nanotube past electrode (BCNTPE) was reviewed trough field emission scanning electron microscopy (FESEM). Results: The functioning SDS/CNTPE shows a voltammetric response with superior sensitivity towards TY. This study was conducted using a phosphate buffer solution having neutral pH (pH=7.0). The correlation between the oxidation peak current of TY and concentration of TY was achieved linearly in CV method, in the range 2.0×10-6 to 5 ×10-5 M with the detection limit 729 nM and limit of quantification 2.43 μM. The investigated voltammetric study at SDS/CNTPE was also adopted in the examination of TY concentration in a pharmaceutical medicine as a real sample with the recovery of 97% to 98% . Conclusion: The modified electrode demonstrates optimum sensitivity, constancy, reproducibility, and repeatability during the electrocatalytic activity of TY.
Keywords: Carbon nanotube; Sodium dodecyl sulfate; Tyrosine; Voltammetry.