Neuroblastoma biosensor system

SKN-B-E(2)C neuroblastoma cells were cultured on poly[(methoxyethoxyethoxy)_1.0(cinammyloxy)_1.0] phosphazene coated indium-tin-oxide (ITO) glass slides for a period of 35 days. Electrical activity was recorded periodically using a custom fabricated flow chamber. At 35-days of culture, "pacemaker" field potentials of 30 microvolts, 1-4 sec^-1 rate were measured from the cell ensemble. The mean inter spike interval (M_isi) for the basal firing rate was measured at 1.5±0.1 sec. Using the flow chamber, the neuroblastoma were stimulated with 0.05 M solution of monosodium glutamate and the neuroelectrical response was recorded. The M_isi for the stimulated cells increased to 0.57±0.1 sec. After rinsing away the monosodium glutamate with fresh culture media, the summed cell firing rate recovered to a baseline rate of 1.5±0.1 sec. Capsaicin was introduced as a mild neurotoxin and was shown to disrupt the uniform firing pattern seen under basal activity. The M_isi for the capsaicin response was 1.5±0.6 sec. The original signal was recovered after rinsing off the capsaicin. Introduction of a 1 μM tetrodotoxin solution extinguished the field potential waveform.