Connecting low cost 3D printing of microfluidic devices

Technology News | February 2, 2022

Researchers at the University of Bristol have extended their low-cost system for prototyping microfluidic devices with an open source, easy to connect format. Microfluidic devices, used in ‘lab-on-a-chip’ technologies, can provide a rapid medical diagnosis at the point of care. These devices can deliver results quickly, rather than waiting for…Read More

By Nick Flaherty

Researchers at the University of Bristol have extended their low-cost system for prototyping microfluidic devices with an open source, easy to connect format.

Microfluidic devices, used in ‘lab-on-a-chip’ technologies, can provide a rapid medical diagnosis at the point of care. These devices can deliver results quickly, rather than waiting for full laboratory tests to confirm a diagnosis. However, they can be expensive to prototype and require specialist equipment.

Dr Robert Hughes, Harry Felton, and Andrea Diaz-Gaxiola developed a fast, reliable, and cost-effective alternative for producing the soft-lithographic moulds used to make microfluidic devices, using simple 3D-printing techniques and digital twin models, building on their work published last year.

The complex microfluidic devices can be built in polydimethylsiloxane (PDMS) using 3D-printed interconnecting microchannel scaffolds. These single-extrusion scaffolds are designed with interconnecting ends and used to quickly configure complex microfluidic systems before being embedded in PDMS to produce an imprint of the microfluidic configuration.

The scaffolds are printed using common Material Extrusion (MEX) 3D printers, achieving a minimum channel cross-section of 100×100 μm. The team also developed a protocol for the rapid fabrication of low-cost microfluidic channel moulds from the thermoplastic 3D-printed scaffolds, allowing the manufacture of customisable microfluidic systems without specialist equipment.

When applied directly to glass, without plasma surface treatment, the microfluidic elements operate efficiently within the typical working pressures.

The team built a fluid-mixer demonstrating the effective interconnecting scaffold design, and a microsphere droplet generator, each for under E0.50.

‘This development could put lab-on-a-chip prototyping into the hands of researchers and clinicians who know the challenges best, in particular, those in resource-limited settings, where rapid diagnostics may often have the greatest impact,” said Hughes, who led the study.

“It’s so simple, quick, and cheap that devices can be fabricated using everyday domestic or educational appliances at a negligible cost,’ said Felton. ‘Researchers could use our technique to fabricate these devices with minimal additional expertise or resources required.’

The team can also see benefits beyond healthcare. By making this technique simple and accessible, they hope to inspire a new generation of engineers and scientists. “The playful click-and-connect approach also makes it suitable for hobbyists and educational use, to teach about microfluidics and the applications of lab-on-a-chip technology,’ said Diaz-Gaxiola.