CMOS electrochemical pH localizer-imager.

Area of Science:

• Biochemistry
• Electrochemistry
• Materials Science

Background:

• pH is crucial for many chemical and biological processes.
• Controlling localized pH environments is essential for high-throughput studies but challenging due to proton diffusion.
• Previous methods lacked the precision and scalability for arrayed pH control.

Purpose of the Study:

• To develop a system for creating and controlling arrayed picoliter-scale pH microenvironments.
• To enable high-throughput studies and applications of pH-dependent processes.
• To demonstrate real-time monitoring and precision control of localized pH.

Main Methods:

• Utilized a 256-electrochemical cell array integrated with complementary metal-oxide-semiconductor (CMOS) electronics.
• Employed sub-nanoampere resolution current control for each cell to generate localized pH 'voxels' via confined electrochemistry.
• Integrated real-time spatiotemporal pH profile monitoring across the array.

Main Results:

• Successfully demonstrated arrayed localization of picoliter-scale aqueous acids.
• Achieved precise, real-time control and monitoring of pH microenvironments.
• Showcased the system's utility in parallelizing pH-gated molecular state encoding and pH-regulated enzymatic DNA elongation.

Conclusions:

• The developed CMOS pH localizer-imager offers a powerful platform for high-throughput investigation of pH-dependent phenomena.
• This technology overcomes the limitations of proton diffusion for precise pH control in microscale environments.
• Enables novel applications in fields requiring localized chemical and biochemical manipulation.