A Low Noise Amplifier System for Nanopore-based Single Molecule Analysis

A novel amplifier system was designed and prepared for low-noise recording of pico-ampere current in nanopore experiment (< 100 pA). As an example, the amplifier system was applied in α-hemolysin based nanopore detection of DNA-PEG-DNA conjugate to record the signals of translocation and bumping events in buffer solution (1 M KCl, 10 mM Tris-HCl, 1 mM EDTA, pH 8.0). The amplified current signal was filtered by a 3 kHz Bessel filter and sampled by a 100 kHz analog-digital convertor. As a result, the presented amplifier system could lower the noise in recording the current. Current blockages (< 10 pA) of single molecules with low amplitude were recovered due to the high signal-to-noise ratio.

Graphical abstractLow-noise recording of pico-ampere current in nanopore analysis was achieved by using the well-designed amplifier system which could help recovering the blockages with low current amplitude.Figure optionsDownload full-size imageDownload as PowerPoint slide