Low cost 3D-printed 'lab-on-chip' device to identify diseases

Scientists have for the first time 3D-printed a low-cost lab-on-chip device that can effectively identify disease biomarkers from blood samples. Microfluidic devices are tiny chips that can sort out biomarkers, cells and other small structures in samples using microscopic channels incorporated into the devices.

"Others have 3D-printed fluidic channels, but they have not been able to make them small enough for microfluidics," said Greg Nordin, professor at Brigham Young University in the US.

"So we decided to make our own 3D printer and research a resin that could do it," said Nordin. Researchers produced labs on a chip with flow channel cross sections as small as 18 micrometres by 20 micrometres. Previous efforts to 3D-print microfluidic devices have failed to achieve success smaller than 100 micrometres.

The researchers' 3D printer uses a 385 nm LED, which dramatically increases the available selection of ultraviolet (UV) absorbers for resin formulation compared to 3D printers with 405 nm LEDs. Nordin said the advantages of 3D printing for microfluidic device fabrication are already well-known and that their method, digital light processing stereolithography (DLP-SLA), is an especially promising lower-cost approach.

DLP-SLA uses a micromirror array chip, like those in most consumer projectors, to dynamically create the optical pattern for each layer during layer-by-layer printing of a device. Researchers said they are laying the foundation for 3D printing to challenge the dominance of conventional methods - soft lithography and hot embossing - of microfluidic prototyping and development. The study was published in the journal Lab on a Chip.