How Meaningful Are Minor Details in the Generation of Nanomodified Electrochemical Enzyme Biosensors? Exploring the Scenario with Sinusoidal Approaches
Md. Towhidur Rahman,
David López-Iglesias,
Alfonso Sierra-Padilla,
Juan José García-Guzmán,
Laura M. Cubillana-Aguilera,
Dolores Bellido-Milla,
José María Palacios-Santander
Affiliations
Md. Towhidur Rahman
Department of Analytical Chemistry, Institute of Research on Electron Microscopy and Materials (IMEYMAT), Faculty of Sciences, Campus de Excelencia Internacional del Mar (CEIMAR), University of Cadiz, Campus Universitario de Puerto Real, S/N. 11510 Puerto Real, Cadiz, Spain
David López-Iglesias
Department of Analytical Chemistry, Institute of Research on Electron Microscopy and Materials (IMEYMAT), Faculty of Sciences, Campus de Excelencia Internacional del Mar (CEIMAR), University of Cadiz, Campus Universitario de Puerto Real, S/N. 11510 Puerto Real, Cadiz, Spain
Alfonso Sierra-Padilla
Department of Analytical Chemistry, Institute of Research on Electron Microscopy and Materials (IMEYMAT), Faculty of Sciences, Campus de Excelencia Internacional del Mar (CEIMAR), University of Cadiz, Campus Universitario de Puerto Real, S/N. 11510 Puerto Real, Cadiz, Spain
Juan José García-Guzmán
Instituto de Investigación e Innovación Biomédica de Cadiz (INiBICA), Hospital Universitario ‘Puerta del Mar’, Universidad de Cadiz, 11009 Cadiz, Spain
Laura M. Cubillana-Aguilera
Department of Analytical Chemistry, Institute of Research on Electron Microscopy and Materials (IMEYMAT), Faculty of Sciences, Campus de Excelencia Internacional del Mar (CEIMAR), University of Cadiz, Campus Universitario de Puerto Real, S/N. 11510 Puerto Real, Cadiz, Spain
Dolores Bellido-Milla
Department of Analytical Chemistry, Institute of Research on Electron Microscopy and Materials (IMEYMAT), Faculty of Sciences, Campus de Excelencia Internacional del Mar (CEIMAR), University of Cadiz, Campus Universitario de Puerto Real, S/N. 11510 Puerto Real, Cadiz, Spain
José María Palacios-Santander
Department of Analytical Chemistry, Institute of Research on Electron Microscopy and Materials (IMEYMAT), Faculty of Sciences, Campus de Excelencia Internacional del Mar (CEIMAR), University of Cadiz, Campus Universitario de Puerto Real, S/N. 11510 Puerto Real, Cadiz, Spain
In this work, a screening of Sonogel-Carbon (SNGC) electrodes modified with nanomaterials (carbon nanotubes and gold nanoparticles) and the study of their effect on the electrochemical performance of sinusoidal voltage (SV) and current (SC)-based biosensors are reported. Surface modification was achieved by drop-casting and electrodeposition methodologies. Within the strategies used, SV and SC, recently exploited procedures, were used to electrodeposit simultaneously a poly 3,4-ethylenedioxythiophene (PEDOT)-tyrosinase layer and the corresponding nanostructured material. Dopamine was selected as a benchmark analyte to evaluate the analytical performance of the different (bio)sensors obtained in terms of relevant figures of merit, such as sensitivity, limits of detection and quantitation, and accuracy, among others. A discussion about the pros and cons between the type of modification and the methods employed is also presented. Briefly, SC based sensors offered excellent quality analytical parameters and lower dispersion of the results. They were employed for more specific electrochemical studies, including interferences assays and the determination of DA in real samples, obtaining good recoveries (101–110.6%). The biosensor modified with gold nanoparticles (AuNPs) (drop-casting method) and SC-electrodeposited showed the best figures of merit: R2 = 0.999; sensitivity = −4.92 × 10−9 A·µM−1; RSDsensitivity = 1.60%; LOD = 5.56 µM; RSDLOD = 6.10%; and LOQ = 18.53 µM.
