LED Optrode with Integrated Temperature Sensing for Optogenetics

• Type: Article in International Scientific Journal
• Date: 2018

Authors

Goncalves, SB (Author) Other; Palha, JM (Author) Other; Fernandes, HC (Author) Other; Souto, MR (Author) Other; Pimenta, S (Author) Other; Dong, T (Author) Other; Yang, ZC (Author) Other; Ribeiro, JF (Author) Other; Correia, JH (Author) Other

Journal

Title: Micromachines

Vol. 9 No. 5

Final page: 473

ISSN: 2072-666X

Publisher: MDPI

Indexing

ISI Web of Knowledge - 1 Citation

Scopus - 6 Citations

Other information

Authenticus ID: P-00P-T36

DOI: 10.3390/mi9090473

Abstract (EN): In optogenetic studies, the brain is exposed to high-power light sources and inadequate power density or exposure time can cause cell damage from overheating (typically temperature increasing of 2 degrees C). In order to overcome overheating issues in optogenetics, this paper presents a neural tool capable of assessing tissue temperature over time, combined with the capability of electrical recording and optical stimulation. A silicon-based 8 mm long probe was manufactured to reach deep neural structures. The final proof-of-concept device comprises a double-sided function: on one side, an optrode with LED-based stimulation and platinum (Pt) recording points; and, on the opposite side, a Pt-based thin-film thermoresistance (RTD) for temperature assessing in the photostimulation site surroundings. Pt thin-films for tissue interface were chosen due to its biocompatibility and thermal linearity. A single-shaft probe is demonstrated for integration in a 3D probe array. A 3D probe array will reduce the distance between the thermal sensor and the heating source. Results show good recording and optical features, with average impedance magnitude of 371 k Omega, at 1 kHz, and optical power of 1.2 mW.mm(2) (at 470 nm), respectively. The manufactured RTD showed resolution of 0.2 degrees C at 37 degrees C (normal body temperature). Overall, the results show a device capable of meeting the requirements of a neural interface for recording/stimulating of neural activity and monitoring temperature profile of the photostimulation site surroundings, which suggests a promising tool for neuroscience research filed.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 14