title: Durability of high surface area platinum deposits on microelectrode arrays for acute neural recordings.
abstract: The durability of high surface area platinum electrodes during acute intracerebral measurements was investigated. Electrode sites with extremely rough surfaces were realized using electrochemical deposition of platinum onto silicon-based microelectrode arrays from a lead-free platinizing solution. The close to 1000-fold increase in effective surface area lowered impedance, its absolute value at 1 kHz became about 7 and 18 % of the original Pt electrodes in vitro and in vivo, respectively. 24-channel probes were subjected to 12 recording sessions, during which they were implanted into the cerebrum of rats. Our results showed that although on the average the effective surface area of the platinized sites decreased, it remained more than two orders of magnitude higher than the average effective surface area of the original, sputtered thin-film platinum electrodes. Sites with electrochemical deposits proved to be superior, e.g. they provided less thermal and 50 Hz noise, even after 12 penetrations into the intact rat brain.
authors: Department of Comparative Psychophysiology, Institute of Cognitive Neuroscience and Psychology, RCNS, HAS, Victor Hugo u. 18-22, Budapest, 1132, Hungary, marton.gergely@ttk.mta.hu.
authors: Gergely
authors: G
authors: Márton
authors: István
authors: I
authors: Bakos
authors: Zoltán
authors: Z
authors: Fekete
authors: István
authors: I
authors: Ulbert
authors: Anita
authors: A
authors: Pongrácz
mesh_terms: D000200:Action Potentials / Q000502:physiology*; D000327:Adsorption; D000818:Animals; D001921:Brain / Q000502:physiology*; D020099:Coated Materials, Biocompatible / Q000737:chemistry; D017097:Electric Impedance; D004569:Electroencephalography / Q000295:instrumentation*; D004595:Electroplating; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006244:Hardness; D046228:Microarray Analysis / Q000295:instrumentation*; D008839:Microelectrodes; D009474:Neurons / Q000502:physiology*; D010984:Platinum / Q000737:chemistry*; D051381:Rats; D017208:Rats, Wistar; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013314:Stress, Mechanical; D013718:Tensile Strength
chemical_list: D020099:Coated Materials, Biocompatible; D010984:Platinum