Study of a novel fabrication method of 3D Ag-based nanoporous structures for electrochemical detection

In this paper, a novel two-step facile strategy was first proposed to fabricate nanoporous Ag (NP-Ag) and nanoporous Ag/AgCl (NP-Ag/AgCl) materials to simplify manufacturing procedure, shorten processing time, and optimize experiment condition. Co-electrodeposition of Ag Sn alloy on the interdigital gold electrode (IGE) and subsequent electrochemical dealloying in HCl solution by applying different potentials. The surface morphologies as well as the electrochemical characterizations of the fabricated NP-Ag and NP-Ag/AgCl IGEs were investigated. The fabricated NP-Ag IGEs were evaluated as biomolecules simultaneous electrochemical sensors for determination of acetaminophen (AC) and dopamine (DA). In addition, the performance of the fabricated NP-Ag/AgCl IGEs, as micro-size reference electrodes , were studied. The NP-Ag electrodes were found promising linear current response to AC (correlation coefficient, R 2  = 0.9906) and DA (correlation coefficient, R 2  = 0.9961), under the concentration ranges from 0.5 to 290 μM and 0.25 to 500 μM, respectively. Moreover, the fabricated NP-Ag/AgCl IGEs were possessed of enhanced stability and miniature size as pseudo-reference electrodes (p-REs) in contrast with commercial p-REs, which benefiting from abundant ion-exchange sites and quantities of nanochannels on the sponge-like surface. Results demonstrated the innovative surface modification of as-synthesized NP-Ag and NP-Ag/AgCl have positive implication for massive production of nanoporous Ag-based materials and the utilization of prospective point-of-care testing.