Electrochemical Methods for Determination of Three Tumour Biomarkers for Neuroblastoma: Homovanillic Acid, Vanillylmandelic Acid, and 5-Hydroxyindoleacetic Acid

Tumour biomarkers - homovanillic acid, vanillylmandelic acid, and 5-hydroxyindoleacetic acid - have been determined at a screen-printed carbon electrode in small volume samples.For all measurements,Britton-Robinson buffer (0.04 mol(-1) , pH 3.0) was used as an optimum medium for three analytes. Dependences of the peak current on the concenteration were linear for all compounds, with the limits of quantification 0.8 mu mol.l(-1) for homovanillic acid, 0.2 mu mol.l(-1) for vanillylmandelic acid, and 0.2 mu mol.l(-1) for 5-hydroxyindoleacetic acid.Depending on the results of the measurements , the future experiments should be performed in human urine.