Department of Electronic and Information Engineering, Toyohashi University of Technology, 1-1 Hibarigaoka, Tempaku-cho, Toyohashi, Aichi 441-8580, Japan.
Biosens Bioelectron. 2011 Jan 15;26(5):2368-75. doi: 10.1016/j.bios.2010.10.014. Epub 2010 Oct 16.
In order to record multi-site electroretinogram (ERG) responses in isolated carp retinae, we utilized three-dimensional (3D), extracellular, 3.5-μm-diameter silicon (Si) probe arrays fabricated by the selective vapor-liquid-solid (VLS) growth method. Neural recordings with the Si microprobe exhibit low signal-to-noise (S/N) ratios of recorded responses due to the high-electrical-impedance characteristics of the small recording area at the probe tip. To increase the S/N ratio, we designed and fabricated enlarged gold (Au) tipped Si microprobes (10-μm-diameter Au tip and 3.5-μm-diameter probe body). In addition, we demonstrated that the signal attenuation and phase delay of ERG responses recorded via the Si probe can be compensated by the inverse filtering method. We conclude that the reduction of probe impedance and the compensation of recorded signals are useful approaches to obtain distortion-free recording of neural signals with high-impedance microelectrodes.
为了记录离体鲤鱼视网膜的多部位视网膜电图（ERG）反应，我们利用了通过选择性气相-液相-固相（VLS）生长法制备的三维（3D）、细胞外、3.5μm 直径硅（Si）探针阵列。由于探针尖端小的记录区域的高电阻特性，Si 微探针的神经记录表现出低的记录响应的信噪比（S/N）。为了提高 S/N 比，我们设计并制造了放大的金（Au）尖端 Si 微探针（10μm 直径 Au 尖端和 3.5μm 直径探针体）。此外，我们证明了通过逆滤波方法可以补偿通过 Si 探针记录的 ERG 响应的信号衰减和相位延迟。我们得出结论，减小探针阻抗和补偿记录信号是获得高阻抗微电极无失真记录神经信号的有用方法。
