Development of a Low Cost & Low Noise Amplification System For In Vitro Neuronal Recording through Microelectrode...

In order to effectively record from electrically active cells through microelectrode arrays a low-noise amplification and data acquisition system is required. Although commercially available, these systems can be expensive and lack the freedom to customise hardware and software. In this work we present a low-cost (US$21 for the first channel + US$11 for each additional channel), low-noise amplifier coupled with an analog to digital converter from National Instruments. The amplifier was designed to (i) operate between 0 and 5 V utilising a DC battery power supply, (ii) operate within a bandwidth of 10 kHz, (iii) remove DC voltage created at the electrode/electrolyte interface with a high-pass cut-off frequency of 0.7 Hz and (iv) have a gain of 2000. Strategies to reduce environment electromagnetic interference at the amplifier front end were employed and involved a customised neural interface board connected between the microelectrode array and amplifier. The constructed amplifier achieved an intrinsic noise amplitude of 0.8 μV_rms, which facilitated high quality recordings as exemplified by in vitro recordings from primary hippocampal neurons.