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Light Color-Controlled pH-Adjustment of Aqueous Solutions Using Engineered Proteoliposomes.
Daniel Harder1,2, Noah Ritzmann2,3, Zöhre Ucurum1
1Institute of Biochemistry and Molecular Medicine, University of Bern, Bern, 3012, Switzerland.
Advanced Science (Weinheim, Baden-Wurttemberg, Germany)
|February 11, 2024
Summary
This study introduces a novel vesicular system that uses different light colors to control pH changes at the microliter scale. This light-driven pH adjustment offers precise control for applications in synthetic biology and microfluidics.
Area of Science:
- Synthetic biology
- Microfluidics
- Biochemistry
Background:
- Precise pH control at the microliter scale is crucial for various research, medical, and industrial applications.
- Existing methods for microscale pH control can be limited in resolution and flexibility.
Purpose of the Study:
- To develop a light-controllable vesicular system for precise pH adjustment at the microliter scale.
- To demonstrate the system's capability in controlling pH-sensitive processes.
Main Methods:
- Engineered proteoliposomes incorporating bacteriorhodopsin and proteorhodopsin (Med12) oriented oppositely in the lipid membrane.
- Utilized different light colors to drive proton pumps and induce pH changes.
- Implemented a computer-controlled feedback loop for automatic pH maintenance.
Main Results:
- Achieved light-induced pH changes in the surrounding solution.
- Demonstrated a pH control range of over two units with fine temporal and pH resolution.
- Successfully controlled the progress of a pH-sensitive enzyme reaction using light color.
Conclusions:
- Engineered proteoliposomes offer a novel method for light-controlled pH adjustment at the microliter scale.
- This technology enables new possibilities for controlling microscale processes in synthetic biology and other fields.
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