Author(s): Li, YM (Li, Yamin); Wang, Y (Wang, Yang); Chen, HD (Chen, Hongda); Wang, YJ (Wang, Yijun); Liu, YY (Liu, Yuanyuan); Pei, WH (Pei, Weihua)

Source: ACTA PHYSICO-CHIMICA SINICA Volume: 36 Issue: 12 Article Number: 1912054 DOI: 10.3866/PKU.WHXB201912054 Published: DEC 15 2020

Abstract: Optogenetics transforms specific types of neurons through genetic engineering to achieve the call membrane expression of photosensitive channel protein. When a specific wavelength of light irradiates the photosensitive channel protein, the cell is either excited of inhibited. Optogenetics provides a precise and fast method to control the activity of individual neurons for neuroscience research, which has gained increasing attention as means of neural regulation. To realize the photogenetic regulation of neurons, light should be introduced into the brain safely and efficiently. Thus, specialized photoelectric devices are needed. Optrode plays a significant role in the application of optogenetics tools, which is the technical basis for the application of optogenetics. Optrode is a kind of implantable neural interface device. It can introduce light into the brain to regulate neural activity and record the changes of neural electrical signals under the control of lights. As the research of optogenetic technology continues, More and more optrodes are being developed and applied in the study of neuroscience and diseases, such as neural circuit, cognition and memory, epilepsy, and sensory function damage. The combination of optrode with optogenetic technologies provides various developmental modes in terms of material selection, device structure, light supply method, and integrated ways. The difficulty in fabricating optrodes lies in performing light stimulation and electrical signal recording without causing the immune rejection of the test animal and affecting its normal physiological activities simultaneously. In this study, based on structural characteristics and manufacturing process, optrodes are classified into two categories: waveguide-based and micro-light emitting diode-based. Subsequently, based on manufacturing process and light supply method, waveguide-based optrodes are further divided into optical fiber-optrode, optical waveguide-optrode based on MENS technology, and LD/LED waveguide-optrode. Similarly, micro-light emitting diode-based optrodes are divided into hard mu LED optrode and soft mu LED optrode. The advantages and disadvantages of different types of optrodes, as well as the evolution direction, are reviewed and summarized. Additionally, problems with existing optrodes, such as signal quality, biocompatibility, and device reliability, are discussed. Further, the ideal form of the device is presented as possessing the following characteristics: mu LED and recording electrode integrated on flexible substrate, small size, high spatial resolution, high biocompatibility, wireless energy supply, wireless data transmission, etc. As optrode technologies are continuously updated, in the application of optogenetic technologies, research on brain neural circuit and functional structure will be better studied, and various nerve diseases will be gradually tamed.

Accession Number: WOS:000607780200004

ISSN: 1000-6818

Full Text: http://www.whxb.pku.edu.cn/EN/10.3866/PKU.WHXB201912054