Biomaterials for the central nervous system

Abstract

Biomaterials are widely used to help treat neurological disorders and/or improve functional recovery in the central nervous system (CNS). This article reviews the application of biomaterials in (i) shunting systems for hydrocephalus, (ii) cortical neural prosthetics, (iii) drug delivery in the CNS, (iv) hydrogel scaffolds for CNS repair, and (v) neural stem cell encapsulation for neurotrauma. The biological and material requirements for the biomaterials in these applications are discussed. The difficulties that the biomaterials might face in each application and the possible solutions are also reviewed in this article.

A new type of recording chamber with an easy-to-exchange microdrive array for chronic recordings in macaque monkeys

“…A challenging problem in chronic recordings is long-term stability of electrodes and recording sites, i.e., obtaining single-and multiunit activity even several months or years following implantation (Hatsopoulos and Donoghue 2009; Polikov et al 2005;Zhong and Bellamkonda 2008). Within cortical tissue, chronically implanted electrodes are likely to induce foreign body reactions like local inflammation processes (Biran et al 2005;McConnell et al 2009), encapsulation of the recording surface (Schmidt et al 1976;Szarowski et al 2003;Turner et al 1999), and formation of glial scars (Griffith and Humphrey 2006), thereby increasing electrode impedance (Grill and Mortimer 1994;Newbold et al 2004;Williams et al 2007) and the distance between electrode tips and nearby neurons (Liu et al 1999).…”

Stretchable silicon nanoribbon electronics for skin prosthesis

“…In addition, there are various mechanical motions of adjacent muscles, which require deformations of the interfacing electrodes to preserve mechanically conformal contacts and prevent scar formation arisen from mechanical mismatch between biological tissues and MEA 33 . Furthermore, inflammations at interfaces between electrodes and nerves induced by reactive oxygen species (ROS) 34 must be suppressed, since massive inflammatory responses can cause death of nervous cells 35 and damage the peripheral nervous system. Corresponding electrophysiological responses recorded from the VPL of the thalamus in the right hemisphere (bottom).…”

Bioactive Nanomaterials for Neural Engineering

“…Generally, poly(alkylcyanoacrylates) (PACAs), polyacetates, polysaccharides, and copolymers are used for NP synthesis (Garcia-Garcia et al 2005 ). For instance, drugs including dalargin, loperamide, tubocurarine, and doxorubicin have been delivered to the CNS by Polybutylcyanoacrylate (PBCA) NPs (Zhong and Bellamkonda 2008 ). NPs can also be coated with hydrophilic polymers, such as PEG, to increase their uptake (Brigger et al 2002 ).…”

“…Therefore, by combining the effect of PEG on extended circulation time and specifi city due to an antibody or a ligand conjugation, delivery can be obtained through the BBB. Liposomes have been used for the treatment of CNS diseases including brain tumors, infection, and ischemia (Zhong and Bellamkonda 2008 ).…”