Empirical study of unipolar and bipolar configurations using high resolution single multi-walled carbon nanotube electrodes for electrophysiological probing of electrically excitable cells

摘要: Identifying the neurophysiological basis underlying learning and memory in mammalian central nervous system requires development of biocompatible, high resolution, low electrode impedance electrophysiological probes; however, physically, will always be finite and, at times, large. Herein, we demonstrate through experiments performed on frog sartorius muscle that single multi-walled carbon nanotube (sMWNT electrode) geometry placement are two degrees freedom can improve biocompatibility probe counteract detrimental effects MWNT/electrolyte interface stimulation efficiency signal-to-noise ratio (SNR). We show aspect dependent electric field enhancement MWNT tip boost efficiency. Derivation sMWNT electrode's electrical equivalent indicates that, stimulus voltage regimes below 1 V, current conduction is mediated by charge fluctuation double layer obviating electrolysis water, which potentially toxic to pH sensitive biological tissue. Despite accompanying increase impedance, a pair closely spaced electrodes (bipolar) configuration maintains enhances SNR compared (unipolar) configuration. For voltages verifies still proceeds via layer. As an extracellular electrode, comprise dipole concentrates density smaller region sartorius; consequently, bipolar elicit fiber twitching preclude water. When recording potentials, subtracts potential between points allowing for detection higher signal amplitudes. result, improved. These results indicate use achieve biocompatible offers enhanced SNR.