Ultrasensitive gold micro-structured electrodes enabling the detection of extra-cellular long-lasting potentials in astrocytes populations

• Type: Article in International Scientific Journal
• Date: 2017

Authors

Mestre, ALG (Author) Other; Cerquido, M (Author) Other; Inacio, PMC (Author) Other; Asgarifar, S (Author) Other; Lourenco, AS (Author) Other; Cristiano, MLS (Author) Other; Paulo Aguiar (Author) FMUP; Medeiros, MCR (Author) Other; Araujo, IM (Author) Other; ventura, j. (Author) FCUP; Gomes, HL (Author) Other

Journal

Title: Scientific Reports

Vol. 7

ISSN: 2045-2322

Publisher: Springer Nature

Indexing

ISI Web of Knowledge - 11 Citations

Scopus - 11 Citations

Other information

Authenticus ID: P-00N-5XG

DOI: 10.1038/s41598-017-14697-y

Abstract (EN): Ultra-sensitive electrodes for extracellular recordings were fabricated and electrically characterized. A signal detection limit defined by a noise level of 0.3-0.4 mu V for a bandwidth of 12.5 Hz was achieved. To obtain this high sensitivity, large area (4 mm(2)) electrodes were used. The electrode surface is also micro-structured with an array of gold mushroom-like shapes to further enhance the active area. In comparison with a flat gold surface, the micro-structured surface increases the capacitance of the electrode/electrolyte interface by 54%. The electrode low impedance and low noise enable the detection of weak and low frequency quasi-periodic signals produced by astrocytes populations that thus far had remained inaccessible using conventional extracellular electrodes. Signals with 5 mu V in amplitude and lasting for 5-10 s were measured, with a peak-to-peak signal-to-noise ratio of 16. The electrodes and the methodology developed here can be used as an ultrasensitive electrophysiological tool to reveal the synchronization dynamics of ultra-slow ionic signalling between non-electrogenic cells.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 11