Electrochemical dopamine sensor using a nanoporous gold microelectrode: a proof-of-concept study for the detection of dopamine release by scanning electrochemical microscopy

Autor(es)

Catota Saenz, Henry Steven ^{[1, 2]} ; Patricio Hernandez-Saravia, Lucas ^{[1, 3]} ; Selva, Jessica S. G. ^[1] ; Sukeri, Anandhakumar ^[1] ; Javier Espinoza-Montero, Patricio ^[4] ; Bertotti, Mauro ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Chem, Dept Fundamental Chem, Av Prof Lineu Prestes 748, Sao Paulo, SP - Brazil

^[2] Escuela Politec Nacl, Fac Ingn Quim & Agroind, Ladron de Guevara E11-253, POB 17-01-2759, Quito 170525 - Ecuador

^[3] Univ Tarapaca, Dept Chem, Gen Velasquez 1577, Arica, Arica & Parinac - Chile

^[4] Pontificia Univ Catolica Ecuador, Escuela Ciencias Quim, Ave 12 Octubre & Roca, Apartado 17-01-2184, Quito, Pichincha - Ecuador

• Tipo de documento: Artigo Científico
• Fonte: Microchimica Acta; v. 185, n. 8 AUG 2018.
• Citações Web of Science: 19

Resumo

Nanoporous gold (NPG) structures were prepared on the surface of a gold microelectrode (Au-mu E) by an anodization-reduction method. Cyclic voltammetry and field emission scanning electron microscopy were used to study the electrochemical properties and the morphology of the nanostructured film. Voltammetry showed an improved sensitivity for dopamine (DA) oxidation at this microelectrode when compared to a bare gold microelectrode, with a peak near 0.2 V (vs. Ag/AgCl) at a scan rate of 0.1 V s(-1). This is due to the increased surface area and roughness. Square wave voltammetry shows a response that is linear in the 0.1-10 mu mol L-1 DA concentration range, with a 30 nmol L-1 detection limit and a sensitivity of 1.18 mA (mu mol L-1)(-1) cm(-2). The sensor is not interfered by ascorbic acid. The reproducibility, repeatability, long-term stability and real sample analysis (spiked urine) were assessed, and acceptable performance was achieved. The ``proof-of-concept{''} detection of dopamine release was demonstrated by using scanning electrochemical microscopy (SECM) with the aim of future applications for single cell analysis. (AU)

• Processo FAPESP: 14/15215-5 - Fabricação e caracterização de nanoeletrodos para uso em microscopia eletroquímica: aplicações analíticas e de caráter fundamental
• Beneficiário: Sukeri Anandhakumar
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 15/20776-9 - Fabricação de sondas com dimensões nanométricas para o estudo de processos bioquímicos usando Microscopia Eletroquímica
• Beneficiário: Mauro Bertotti
• Modalidade de apoio: Auxílio à Pesquisa - Regular