Point-of-Care Sensor Using Modified Nickel-doped Zinc Oxide Nanoparticle Carbon Paste Electrode for Homovanillic Acid Cancer Biomarker Detection in Urine

Abstract

The prevalence of cancer worldwide has prompted efforts to develop and produce a range of electrochemical biosensors for cancer diagnosis. Efficient cancer diagnosis can be enhanced by the sensitive detection of biomarkers, which can also lower the cost of medical diagnostics. Neuroblastoma is an embryonic cancer arising from neural crest stem cells and is considered the most common malignancy in infants and the extracranial solid tumor in children. In this paper, we describe the construction of a nanoparticle-modified electrochemical sensor for detecting and quantifying homovanillic acid (HVA), a biomarker for neuroblastoma. The electrooxidation of HVA was studied at a carbon paste electrode (CPE) modified with nickel-doped zinc oxide nanoparticles (Ni-ZnO NPs). The use of these nanoparticles enhanced electrochemical sensitivity and the electrocatalytic activity. The differential pulse voltammetric response of HVA was found to be linear in the concentration range of (3.96 × 10 −6 to 3.83 × 10 −5 M) with a lower detection limit of 1.01 × 10 −6 M. The electrode demonstrated good stability in the HVA determination process, with a minor decrease in response after 10 weeks. The proposed sensor was successfully applied to determine HVA in a urine sample with a good detection result and a worthwhile biological impact. A carbon paste electrode with nickel-doped zinc oxide nanoparticles was developed. The proposed sensor was used to detect homovanillic acid as cancer biomarker. The neuroblastoma biomarker was determined with good selectivity and sensitivity. The suggested sensor was effectively used to measure homovanillic acid in a urine sample.