Facile development of Au-ring microelectrode for in vivo analysis using non-toxic polydopamine as multifunctional material

Sensitive Electrochemical Detection of Nitric Oxide Release from Cardiac and Cancer Cells via a Hierarchical Nanoporous Gold Microelectrode

“…As the cycle numbers of alloying/dealloying were increased from 10 to 50, the reduction peak of gold oxide was gradually increased, while as the alloying/dealloying cycles were further increased to 60 cycles, the reduction peak of gold oxide was decreased. The ECSA of the HNG microelectrodes prepared under different cycles was estimated by integrating the charge associated with the reduction peak of gold oxide centered at ∼+0.90 V. , The roughness factor expressed as the ratio between the ECSA and the geometrical area of electrode was calculated, where the geometrical surface area of the gold microwire electrode was 0.848 mm 2 as listed in Table S-1. It was found that the HNG microelectrode treated after 50 cycles possessed the highest surface area, which was determined to be 25.0 mm 2 by assuming that the reduction of a monolayer of gold oxide was 390 μC cm –2 , and the roughness factor was thus calculated to be 29.5, which was consistent with the aforementioned SEM images displayed in Supporting Information Figure S-2.…”

Recent Advances in In Vivo Neurochemical Monitoring

“…CA can be performed using either a three-electrode set up consisting of a working electrode, a reference electrode, and a counter electrode, or a two-electrode set up where the reference and counter are shorted together. The working electrode is often a carbon-based material, but in many studies can also be metal-based-e.g., platinum or gold, due to their advantages in conductivity [35], biocompatibility [36], stable potential window [37], and electrocatalytic activity [38][39][40]. The reference electrode provides a stable standard potential so that the voltage at the working electrode can be controlled.…”

“…Although carbon materials have many advantages, fabricating carbon-based electrodes or microelectrode arrays has been challenging because of the long, costly process of micromanufacturing and the difficulty in scaling up the fabrication of high-density carbon electrodes with 3D arrangements [94]. Metal electrodes do not offer the same advantages as carbon in terms of electrochemical stability and a wide electrochemical window, but they have some desirable chemical properties, such as the ease of adding surface modifications to immobilize biorecognition elements and electrocatalytic behavior towards specific redox active species [38,[95][96][97]. In order to improve charge transfer rates, decrease oxidation potentials, and increase sensitivity while still being able to achieve good selectivity, metal electrodes modified with ionic liquids and novel polymers have attracted significant attention in the development of new electrochemical sensors [98][99][100].…”

Noninvasive Strategy Based on Real-Time in Vivo Cataluminescence Monitoring for Clinical Breath Analysis

“…Direct measurement of chemical compounds in live organisms remains a technical challenge and an ethical issue . Because of its ability to measure the chemical compounds of interest to noninvasively observe the biochemical processes in the living organism, in vivo analysis is recognized as a powerful and widely applicable tool for biological and medical research as well as clinical diagnosis. , Over the last several decades, a great deal of endeavor has been done toward developing such a field, and many innovative methods based on different principles including infrared spectroscopy, , fluorescence spectroscopy, − chemiluminescence, − Raman spectroscopy, − electrochemistry, , mass spectrometry, − and nuclear magnetic resonance − have been developed for in vivo analysis. Recently, intensive research has been focused on the development of rapid, inexpensive, and real-time in vivo analytical methods.…”