Gold Nanoparticle Layer by Layer Assembled Nanostructures for Neural Interface

Electrical stimulation is a technique for diagnosis and therapy of many neurological diseases. We often utilize a neural prosthetic device (NPD) to deliver the electrical stimulation.[1, 2] The common clinical NPDs have several problems, such as low charge storage capacity, large size , chronic inflammatory response, and mismatch of mechanical properties with brain tissue.[3] In order to improve the current design of NPDs, we need to design nanocomposite materials that exhibit superior properties and functionalities than current materials. Layer by layer (LBL) assembled gold nanoparticle (Au NP) multilayers are composite materials made from gold nanoparticles and polyelectrolyte polymers. Nanocomposite materials made from combining nanoparticles and LBL assembly technique have superior electrochemical properties, long term chemical stability,and tunable mechanical properties. These remarkable properties are very attractive for chronically implanted NPDs.[4] The versatility of the LBL assembly enables us to easily modify current clinical NPDs to create multifunctional devices. As a coating material, LBL assembled Au NP nanocomposite can potentially improve the performance of implantable NPD by increasing its charge injection capacity and decrease electrical impedance. In addition, we could also create freestanding LBL assembled Au NP film to directly fabricate flexible implantable electrodes. Reference: 1. Merrill, D.R., M. Bikson, and J.G. Jefferys, Electrical stimulation of excitable tissue: design of efficacious and safe protocols. J Neurosci Methods, 2005. 141(2): p. 171-98. 2. Benabid, A.L., Deep brain stimulation for Parkinson's disease. Curr Opin Neurobiol, 2003. 13(6): p. 696-706. 3. Kotov, N.A., et al., Nanomaterials for Neural Interfaces. Advanced Materials, 2009. 21(40): p. 3970-4004. 4. Cogan, S.F., Neural stimulation and recording electrodes. Annu Rev Biomed Eng, 2008. 10: p. 275-309.