Journal: Micromachines

Article Title: Carbon Nanotube-Based Printed All-Organic Microelectrode Arrays for Neural Stimulation and Recording

doi: 10.3390/mi15050650

Figure Lengend Snippet: Characterization of the microelectrodes for neural recording. ( a ) Electrical impedance at the frequency of 1 kHz of three types of the microelectrode: totally insulated electrodes, electrodes with locally exposed insulation layer without O 2 plasma treatment, and the electrodes with O 2 plasma treatment. Dot plots show raw data (n = 10 for each type of electrodes) and bars shows their mean values. Width and depth of the electrode were 250 μm and 90 μm, respectively. ( b ) Recorded model sinusoidal electrical signals at the frequency of 1 kHz in physiological saline with conventional Ag/AgCl electrode ( top ), with CNT/paraffin electrode without insulation layer ( middle ), and with CNT/paraffin electrode with O 2 plasma-treated locally exposed insulation layer ( bottom ).

Article Snippet: The cells were previously maintained in Dulbecco’s Modified Eagle Medium (Advanced DMEM, 12491015, Thermo Fisher Scientific, Waltham, MA, USA) containing 10% ( v / v ) fetal bovine serum (FBS, S-FBS-NL-015, Serana Europe, Brandenburg, Germany), 2% ( v / v ) L-glutamine (Sigma-Aldrich), and 1% ( v / v ) penicillin-streptomycin (Sigma-Aldrich) in a humidified 37 °C incubator with 5% CO 2 (MCO-5ACUV-PJ, PHC, Tokyo, Japan), and passaged at a 1:3 ratio using trypsin-EDTA (Sigma-Aldrich) every 3 d. When culturing PC12 cells on the fabricated electrodes, the electrodes were treated with O 2 plasma using a plasma processing device (PC-400, STREX, Osaka, Japan) for 20 s and then washed using serum-free Advanced DMEM containing 100 ng mL −1 of nerve growth factor (NGF, 2.5S from murine submaxillary gland, Sigma-Aldrich), 2% ( v / v ) L-glutamine (Sigma-Aldrich) and 1% ( v / v ) penicillin-streptomycin for nerve differentiation.

Techniques: Insulation, Saline