Affiliation:
1. Microelectronics Lab (meLAB) James Watt School of Engineering University of Glasgow Glasgow G12 8QQ UK
2. Department of Biomedical, Metabolic and Neural Sciences University of Modena and Reggio Emilia Via Campi, 287 41125 Modena Italy
3. Enhanced Regenerative Medicine Fondazione Istituto Italiano di Tecnologia Via Morego 30 16163 Genova Italy
Abstract
Miniaturized, flexible, and biocompatible neural probes have the potential to circumvent the brain's foreign body response, but the problem of surgical implantation remains. Herein, a probe intended for implantation in the rat hippocampus is coated in four bioresorbable stiffeners to determine which is most effective in aiding insertion. The stiffeners (sucrose, maltose, silk fibroin, and alginate) are evaluated through mechanical, chemical, and dissolution tests. After coating with silk fibroin, the buckling force of the neural probe increases from 0.31 to 75.99 mN. This goes in accordance with subsequent successful insertion tests. Fourier transform infrared spectroscopy results demonstrate the increase in β‐sheet content of silk fibroin samples after treatment (e.g., water annealing) and show relevant changes due to dehydration of the alginate hydrogel. Both qualitative and quantitative dissolution studies in artificial cerebrospinal fluid illustrate that alginate and silk fibroin outlasts the disaccharide stiffeners. In this work, a variety of multidisciplinary analyses are carried out to find the best bioresorbable stiffener for deep brain implantable devices with the highest buckling force, longest dissolution time, and the most tunable structure. For the first time, an alginate hydrogel is used as a stiffener to aid insertion, expanding its usefulness beyond neural tissue engineering.
Funder
Engineering and Physical Sciences Research Council
European Commission