To address this problem, the researchers turned to paper-based microfluidics. Paper-based microfluidics is not a new idea. Its previous uses in diagnostic devices are powered by liquid wicking — a process where a liquid can flow due to specific geometries of the chambers without external forces. Common examples of wicking-based paper devices are pregnancy tests and at-home COVID antibody/antigen tests.
While passive fluid handling has helped develop several diagnostic tests, the lack of active fluid control and the resulting variability in capillary transport due to surface evaporation is a major technical limitation for paper-based microfluidic devices.
In contrast, the researchers’ paper microfluidic devices function similarly to traditional plastic microfluidic devices. Their method allows the researchers to fabricate diagnostic devices using laminated paper to guide porous microfluidic continuous flows using external pressure sources such as pumps. In other words, laminated paper can direct fluid through porous paper structures with high accuracy and precision and can be used in complex fluid handling systems such as PCR and DNA sequencing machines.
“Our study showed that we could create diagnostic devices that would normally require precise cleanroom fabrication out of paper that we laminated in our lab and essentially see the same type of flow behavior,” said Gagnon.
Their paper-based diagnostic devices require minimal equipment, can be quickly prototyped and are scaled for manufacturing purposes at a fraction of the cost of traditional microfluidic devices, making an accessible and inexpensive pathway for microfluidic operations.
The porous nature of paper offers several advantages because it allows for continuous fluid flow, broadening the span of applications for paper microfluidic devices. For example, Islam used this fabrication technique to investigate different applications of paper microfluidics, such as studying the elasticity of red blood cells or concentrating DNA. Another graduate student from the chemical engineering department, Jarad Yost, has used this technology to perform DNA amplification using a paper microfluidic device, eliminating the need for large and bulky lab equipment.
“The research offers a potential substitute for traditional microfluidic devices,” said Gagnon. “We have shown there’s enough overlap between paper-based microfluidic designs and traditional designs, providing the opportunity for others in microfluidics to commercialize their products.”
The research was published in Analyst.
Source:Texas A&M University
Source: Healthcare in Europe
