Static and Dynamic Measurement of Dopamine Adsorption in Carbon Fiber Microelectrodes Using Electrochemical Impedance Spectroscopy

Abstract

In this study, electrochemical impedance spectroscopy was used for the first time to study the adsorption of dopamine in carbon fiber microelectrodes. In order to show a proof-of-concept, static and dynamic measurements were taken at potentials ranging from -0.4 to 0.8 V versus Ag|AgCl to demonstrate the versatility of this technique to study dopamine without the need of its oxidation. We used electrochemical impedance spectroscopy and single frequency electrochemical impedance to measure different concentrations of dopamine as low as 1 nM. Moreover, the capacitance of the microelectrodes surface was found to decrease due to dopamine adsorption, which is dependent on its concentration. The effect of dissolved oxygen and electrochemical oxidation of the surface in the detection of dopamine was also studied. Nonoxidized and oxidized carbon fiber microelectrodes were prepared and characterized by optical microscopy, scanning electron microscopy, cyclic voltammetry, and electrochemical impedance spectroscopy. Optimum working parameters of the electrodes, such as frequency and voltage, were obtained for better measurement. Electrochemical impedance of dopamine was determined at different concentration, voltages, and frequencies. Finally, dynamic experiments were conducted using a flow cell and single frequency impedance in order to study continuous and real-time measurements of dopamine.

Measurement of Neuropeptide Y Using Aptamer-Modified Microelectrodes by Electrochemical Impedance Spectroscopy

“…Electrochemical characterization of platinum and carbon fiber was carried out in aCSF at pH 7.4 prepared as reported previously. 3 Neuropeptide Y (GenScript) also diluted in aCSF for the preparation of standard solutions. The master solution was prepared fresh daily at a concentration of 5 μg/ mL and was used to prepare the different standard solutions in the electrochemical cell by addition to the initial 15 mL of aCSF.…”

Recent Advances in In Vivo Neurochemical Monitoring

“…( B ) Exposed area of carbon fiber microelectrode; the scale bar is 2 µm. Adapted with permission from [ 92 ]. ( C ) As-grown vertically aligned carbon nanofibers; the scale bar is 6 µm.…”

“…The resistance of nanodiamond to fouling makes it a highly promising electrode material for future long-term recordings in vivo. [92]. (C) As-grown vertically aligned carbon nanofibers; the scale bar is 6 μm.…”

Nonlinear sensors for biomaterials—Principles and applications

“…A search of PubMed (April 2020) performed with “electrochemical impedance spectroscopy” reveals a vast literature on this subject, with 11,704 results. Four representative examples of this broad biomedical usage are included in the References section (Bohli, Chammem, Meilhac, Mora, & Abdelghani, 2017; Rivera‐Serrano et al., 2018; Singh, Nayak, Patel, Sahoo, & Kumar, 2018; Soares, Tenreiro Machado, Lopes, Vieira, & Delerue‐Matos, 2020). There are 562 publications cited by PubMed (April 2020) using the two search terms of “electrochemical impedance spectroscopy” and “alloys”.…”

“…This work suggests that patients having Co-Cr-Mo orthopaedic implants and long-term exposure to hypochlorous acid within an inflamed joint might suffer the consequences from an accelerated generation of corrosion products.It should be noted that the technique of electrochemical impedance spectroscopy has wide analytical use beyond biomedical alloys.A search of PubMed (April 2020) performed with "electrochemical impedance spectroscopy" reveals a vast literature on this subject, with 11,704 results. Four representative examples of this broad biomedical usage are included in the References section(Bohli, Chammem, Meilhac, Mora, & Abdelghani, 2017;Rivera-Serrano et al, 2018;Singh, Nayak, Patel, Sahoo, & Kumar, 2018;Soares, Tenreiro Machado, Lopes, Vieira, & Delerue-Matos, 2020). There are 562 publications cited by PubMed (April 2020) using the two search…”