Liquid marbles as biochemical reactors for the polymerase chain reaction

Area of Science:

• Biotechnology
• Microfluidics
• Environmental Science

Background:

• Polymerase chain reaction (PCR) is a key DNA amplification technique.
• Microfluidics has advanced PCR, reducing sample volume and cycling time, leading to digital PCR.
• Conventional microfluidic PCR faces challenges like contamination, lack of reusability, and operational complexity.

Purpose of the Study:

• To report the first implementation of polymerase chain reaction (PCR) using liquid marbles.
• To demonstrate a novel microfluidic platform for PCR that addresses drawbacks of existing systems.
• To assess the potential of liquid marble-based PCR for applications like water quality monitoring.

Main Methods:

• Development of an experimental setup for liquid marble-based PCR.
• Utilizing a humidity-controlled chamber with an embedded thermal cycler.
• Employing a concentrated salt solution to manage chamber humidity and reduce liquid marble evaporation.

Main Results:

• Successful amplification of microbial source tracking markers for faecal contamination was achieved.
• The liquid marble platform demonstrated effective DNA amplification.
• The system showed potential for real-world environmental applications.

Conclusions:

• Liquid marbles offer a viable alternative microfluidic platform for polymerase chain reaction (PCR).
• This approach can potentially overcome limitations of conventional microfluidic PCR, including contamination and reusability issues.
• The demonstrated system holds promise for sensitive water quality monitoring through faecal contamination detection.