Development of new ceramic doped ionoconducting membranes for biomedical applications.
- PDF / 195,364 Bytes
- 6 Pages / 612 x 792 pts (letter) Page_size
- 32 Downloads / 213 Views
EE6.1.1
Development of new ceramic doped ionoconducting membranes for biomedical applications. Paola Romagnolia, Maria Luisa Di Vonaa, Enrico Traversaa, Livio Naricib, Walter G. Sannitac, Simone Carozzoc, Marcella Trombettad and Silvia Licocciaa Dipartimento di Scienze e Tecnologie Chimiche, and Dipartimento di Fisica b,Università di Roma “Tor Vergata”, Via della Ricerca Scientifica 1, 00133 Rome (Italy) c Centro Farmaci Neuroattivi-Dipartimento di Scienze Motorie, Universita’ di Genova, Largo Benzi 10, 16132 Genova, Italy and Department of Psychiatry, State University of New York, Stony Brook, NY,1764-8101 USA. d Interdisciplinary Center for Biomedical Research (CIR), Laboratory of Biomaterials, Università “Campus Bio-Medico”, via E. Longoni 83, 00155 Rome (Italy)
a
ABSTRACT New ionoconducting composite membranes to be used as an interface between the skin and the actual electrical instrumentation used to produce an electroencephalogram (EEG) have been developed. The gels are based on lithium salts and PMMA (polymethyl methacrylate) and have been doped with nanometric titanium oxide. The samples have been electrochemically characterized by means of impedance spectroscopy and their structure studied by ATR-FTIR and MAS NMR. Spectroscopic studies indicate interactions between the polymer and oxide dopant. The polymeric electrolytes allowed the registration of good electrophysiological cortical signals either spontaneous or stimulus-related. INTRODUCTION Conventional EEG recording require accurate preparation of the skin and the use of a semi-fluid electrolyte to establish electrical connection with the scalp. These requirements cannot be met if EEG recording has to be performed in extreme conditions (emergency, experimental conditions “on the field”, non-cooperative subjects etc.). Polymer based materials can represent a solution to these problems since they have the proper electrical and mechanical characteristics. Polymeric gels are extensively studied for a variety of biomedical applications [1-3]. The addition of inert ceramic powders into gel membranes has been reported to enhance ionic conductivity and/or to improve the mechanical stability of these materials [4]. We have then developed new composite polymer electrolyte consisting of nanometric titania dispersed in gels formed by immobilizing liquid solution containing LiClO4 and 1,2-diethoxyethane into a PMMA polymer matrix. EXPERIMENTAL DETAILS All chemicals were reagent grade and were used as received. Titania powders were prepared via sol-gel according to a procedure previously described [5]. The electrolyte
EE6.1.2
gels were prepared using the solvent casting technique. LiClO4 was dissolved in 1,2diethoxyethane (gly). PMMA and TiO2 were then added along with EtOH/H2O 9:1. The mixture was heated until complete gelification, then poured on a glass plate and cooled at RT until the volatile casting solvent was completely evaporated favoring cross-linking and solid gel formation. The molar composition (%) was 7.19-64.01-28.80 (Li+-glyPMMA). The ionic cond
Data Loading...
