Zeolite Nanoparticle Modified Carbon Paste Electrode as a Biosensor for Simultaneous Determination of Dopamine and Tryptophan

A new chemically modified electrode is constructed based on an iron(III) doped zeolite modified carbon paste electrode (Fe3+Y/ZCME). The electrode was evaluated as a sensor for sub-micromolar determination of tryptophan (Trp) and dopamine (DA). The measurements were carried out using the differential pulse voltammetry (DPV) method in a phosphate buffer solution with pH = 5. The prepared modified electrode shows voltametric responses with high sensitivity and stability for DA and Trp in optimal conditions. The analytical performance of this sensor has been evaluated for detection of DA and Trp in human serum.