A portable microelectrode array recording system incorporating cultured neuronal networks for neurotoxin detection.
Cultured neuronal networks, which have the capacity to respond to a wide range of neuroactive compounds, have been suggested to be useful for both screening known analytes and unknown compounds for acute neuropharmacologic effects. Extracellular recording from cultured neuronal networks provides a means for extracting physiologically relevant activity, i.e. action potential firing, in a noninvasive manner conducive for long-term measurements. Previous work from our laboratory described prototype portable systems capable of high signal-to-noise extracellular recordings from cardiac myocytes. The present work describes a portable system tailored to monitoring neuronal extracellular potentials that readily incorporates standardized microelectrode arrays developed by and in use at the University of North Texas. This system utilizes low noise amplifier and filter boards, a two-stage thermal control system with integrated fluidics and a graphical user interface for data acquisition and control implemented on a personal computer. Wherever possible, off-the-shelf components have been utilized for system design and fabrication. During use with cultured neuronal networks, the system typically exhibits input referred noise levels of only 4-6 microVRMS, such that extracellular potentials exceeding 40 microV can be readily resolved. A flow rate of up to 1 ml/min was achieved while the cell recording chamber temperature was maintained within a range of 36-37 degrees C. To demonstrate the capability of this system to resolve small extracellular potentials, pharmacological experiments with cultured neuronal networks have been performed using ion channel blockers, tetrodotoxin and tityustoxin. The implications of the experiments for neurotoxin detection are discussed.
Pancrazio
Joseph J
JJ
Center for Bio/Molecular Science and Engineering, Code 6900, Naval Research Laboratory, Washington, DC 20375, USA. jxp@cbmse.nrl.navy.mil
Gray
Samuel A
SA
Shubin
Yura S
YS
Kulagina
Nadezhda
N
Cuttino
David S
DS
Shaffer
Kara M
KM
Eisemann
Kevin
K
Curran
Anthony
A
Zim
Bret
B
Gross
Guenter W
GW
O'Shaughnessy
Thomas J
TJ
D000200:Action Potentials / Q000187:drug effects / Q000502:physiology*; D000818:Animals; D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D018929:Cell Culture Techniques / Q000295:instrumentation* / Q000379:methods; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D004594:Electrophysiology / Q000295:instrumentation / Q000379:methods; D004781:Environmental Exposure / Q000032:analysis; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005240:Feasibility Studies; D016247:Information Storage and Retrieval / Q000379:methods; D051379:Mice; D008813:Mice, Inbred ICR; D008839:Microelectrodes; D008904:Miniaturization; D009415:Nerve Net / Q000187:drug effects* / Q000502:physiology*; D009498:Neurotoxins / Q000032:analysis* / Q000506:poisoning*; D015203:Reproducibility of Results; D012604:Scorpion Venoms / Q000032:analysis / Q000506:poisoning; D012680:Sensitivity and Specificity; D013779:Tetrodotoxin / Q000032:analysis / Q000506:poisoning; D014584:User-Computer Interface
D009498:Neurotoxins; D012604:Scorpion Venoms; C003609:tityustoxin; D013779:Tetrodotoxin