Electroactive smart materials for neural tissue regeneration

Repair in the human nervous system is a complex and intertwined process that offers significant challenges to its study and comprehension. Taking advantage of the progress in fields such as tissue engineering and regenerative medicine, the scientific community has witnessed a strong increase of biomaterial-based approaches for neural tissue regenerative therapies. Electroactive materials, increasingly being used as sensors and actuators, also find application in neurosciences due to their ability to deliver electrical signals to the cells and tissues. The use of electrical signals for repairing impaired neural tissue therefore presents an interesting and innovative approach to bridge the gap between fundamental research and clinical applications in the next few years. In this review, first a general overview of electroactive materials, their historical origin, and characteristics are presented. Then a comprehensive view of the applications of electroactive smart materials for neural tissue regeneration is presented, with particular focus on the context of spinal cord injury and brain repair. Finally, the major challenges of the field are discussed and the main challenges for the near future presented. Overall, it is concluded that electroactive smart materials play an ever-increasing role in neural tissue regeneration, appearing as potentially valuable biomaterials for regenerative purposes.
This work was supported by Prémios Santa Casa Neurociências–Prize Melo e Castro for Spinal Cord Injury Research (MC-04/17) and Portuguese Foundation for Science and Technology (Ph.D. fellowship to T. S. Pinho [PD/BDE/143150/2019]. This work was funded by national funds and FEDER, through the Foundation for Science and Technology (FCT), under the scope of the projects UIDB/50026/2020; UIDP/50026/2020; POCI-01-0145-FEDER-029206; POCI-01-0145-FEDER-031392; PTDC/MED-NEU/31417/2017; NORTE-01-0145-FEDER-029968; POCI-01-0145-FEDER-029751 POCI-01-0145-FEDER-032619. This work has also been developed under the scope of the project NORTE-01-0145-FEDER-000013 and NORTE-01-0145-FEDER-000023, supported by the Northern Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund (FEDER). Work supported by the Portuguese Foundation for Science and Technology (FCT): projects UID/FIS/04650/2020, PTDC/EMD-EMD/28159/2017 and PTDC/BTM-MAT/28237/2017. Financial support from the Spanish State Research Agency (AEI) and the European Regional Development Fund (ERFD) through the project PID2019-106099RB-C43/AEI/10.13039/501100011033 and from the Basque Government Industry and Education Departments under the ELKARTEK and PIBA (PIBA-2018-06) programs, respectively, area also acknowledged.