Ultra-Low Noise Amplifier Array System for High Throughput Single Entity Analysis

Electrochemical measurements at the single entity level provide ultra-sensitive tools for precise diagnosis and understanding of basic biological and chemical processes. By decoding current signatures, the single-entity electrochemistry provides abundant information on charges, sizes, shapes, catalytic performances and compositions. The accuracy of single-entity electrochemistry highly relies on the advanced instrumentation to achieve the amperometric resolution at sub-picoampere level and the temporal resolution at sub-microsecond level. Currently, it is still a challenge for paralleling amplifiers to allow the low-noise and high bandwidth single-entity electrochemical measurements. Herein, we developed a low-noise four-channel electrochemical instrumentation that integrates an Au electrode array with amplifiers in the circuit board. With this amplifier array, we achieved a high bandwidth (> 100 kHz) electrochemical measurements. The further practical experiments proved the capability of this amplifier array system in acquiring transient signals from both single-molecule detection with an Aerolysin nanopore, and single Pt nanoparticle catalysis during the dynamic collision process. Paired with appropriate microfluidic array systems, our instrumentation will enable an extraordinarily high-throughput feature for single-entity sensing.