A team of researchers from three universities have developed a lab-on-a-chip that could revolutionize global health care diagnostics. The Self-powered Integrated Microfluidic Blood Analysis System (SIMBAS) is a stand alone biochip that diagnoses diseases within 10 minutes without the use of external tubing. The development is a major milestone in the field of microfluidics.UC Berkeley, Dublin City University in Ireland and Universidad de Valparaíso Chile worked together to create the device, which can process whole blood samples without electricity, chemicals, or any other components. Luke Lee, a UC Berkley bioengineering professor, told TG Daily that the chip would allow field workers around the world to diagnose blood diseases like HIV and tuberculosis in just a few minutes.
The SIMBAS biochip uses tiny trenches patterned beneath microfluidic channels to separate blood cells from plasma. When whole blood is dropped on the chip, the heavier red and white blood cells sink into the trenches, naturally separating from the plasma. A degas-driven flow then pulls the blood cells through the trenches. A news release from Berkley explains the technology behind degas-driven flow:
Air molecules inside the porous polymeric device are removed by placing the device in a vacuum-sealed package. When the seal is broken, the device is brought to atmospheric conditions, and air molecules are reabsorbed into the device material. This generates a pressure difference, which drives the blood fluid flow in the chip.
In testing, the team used a five-microliter sample of whole blood that contained vitamin b7 at a concentration of about 1 part per 40 billion. They were able to capture more than 99 percent of the blood in the grooves, and the chip provided an accurate readout of biotin levels in 10 minutes.
In a news release, Ivan Dimov, the co-author of the SIMBAS biochip study, said that while other lab-on-a-chips have been created, none of them are truly autonomous like the SIMBAS. Dimov and his fellow researchers reduced the complexity of the chip and used plastic components so it easier and cheaper to manufacture.
“By the time you add tubing and sample prep setup components required to make previous chips function, they lose their characteristic of being small, portable and cheap,” said Dimov. “In our device, there are no external connections or tubing required, so this can truly become a point-of-care system.”
Images © Ivan Dimov