A 256-Channel In-Pixel Electrochemical Platform in CMOS for Rapid Isothermal Genetic Amplification and Screening

This work presents a fully integrated CMOS electrochemical biosensor chip that detects localized and concurrent electrochemical signals from all 256 channels per chip. Each pixel has an individual potentiostat, a current sensor, and three on-chip electrodes, which eliminate the need for external electrodes and address issues of pixel-to-pixel crosstalk. To enhance antifouling robustness and lower interfacial impedance, we propose electropolymerizing a PEDOT:PSS conductive polymer film on the sensing electrodes. This platform utilizes an intercalating redox compound as a signal indicator and achieves an electrode-immobilization-free sensing mechanism. It demonstrates the first on-CMOS isothermal amplification of DNAs and electrochemical detection of DNA sequences, which enables highly sensitive and rapid in situ molecular diagnostic analysis based on molecular amplification, without PCR thermal cycling or intricate laboratory setup.

Automated summary

This work presents a fully integrated CMOS electrochemical biosensor chip that detects localized and concurrent electrochemical signals. Each pixel has an individual potentiostat, a current sensor, and three on-chip electrodes, eliminating the need for external electrodes and addressing issues of pixel-to-pixel crosstalk. By using electropolymerization of a conductive polymer film and an intercalating redox compound, this platform achieves an electrode-immobilization-free sensing mechanism, enabling highly sensitive and rapid molecular diagnostic analysis.