Electrochemically Assaying Dopamine with p-Doped Silicon Nanowires
Nawaraj Karki, Albert Davydov, Sergiy Krylyuk, Charles Chusuei
Neuroblastoma, a pediatric cancer, is characterized by high urinary excretion of dopamine (DA). Silicon nanowires (SiNWs), which are nontoxic and known to resist surface fouling in biological samples, were investigated for practical use as working electrode materials to assay DA. Undoped, p-doped, and n-doped SiNWs were deposited onto glassy carbon electrodes and used to measure DA in aqueous solution. Within this series, p-doped SiNWs had the highest sensitivity in the series and are the focus of this study. Optimum measurements were obtained at pH 5.0. Cyclic voltammetry analyses of DA showed that oxidation at +0.480 V vs Ag/AgCl provided the highest sensitivity and for chronoamperometry (CA) analysis. A calibration curve using CA measurements showed a linear range from 50 µM to 900 µM. Randles-Sevçik analysis showed that the interaction of DA with the electrode surface was diffusion controlled reversibly with coefficients (D) equal to 2.77x10–5 cm2∙s-1 and 2.01x10-5 cm2∙s-1 for the oxidation and reduction potentials, respectively. The sensor was demonstrated to be selective against uric acid, acetaminophen, H2O2, folic acid, and glucose.
, Davydov, A.
, Krylyuk, S.
and Chusuei, C.
Electrochemically Assaying Dopamine with p-Doped Silicon Nanowires, Analytical Letters, [online], https://doi.org/10.1080/00032719.2022.2048845, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=934444
(Accessed June 3, 2023)