University of Michigan researchers have created microfluidic integrated circuits in a bid to simplify lab-on-a-chip devices for quicker, cheaper and more portable medical tests.
Just as electronic circuits intelligently route the flow of electricity on computer chips without external controls, these microfluidic circuits regulate the flow of fluid through their devices without instructions from outside systems.
A microfluidic device, or lab-on-a-chip, integrates multiple laboratory functions onto one chip just centimetres in size.
The devices allow researchers to experiment on tiny sample sizes, and also to simultaneously perform multiple experiments on the same material.
They can be engineered to mimic the human body more closely than the Petri dish does.
They could lead to instant home tests for illnesses, food contaminants and toxic gases, among other advances.
"In most microfluidic devices today, there are essentially little fingers or pressure forces that open and close each individual valve to route fluid through the device during experiments. That is, there is an extra layer of control machinery that is required to manipulate the current in the fluidic circuit," Nature quoted Shu Takayama, the principal investigator on the project, as saying.
"We have literally made a microfluidic integrated circuit," said Bobak Mosadegh, first author of the paper.
The researchers have devised a strategy to produce the fluidic counterparts of key electrical components including transistors, diodes, resistors and capacitors, and to efficiently network these components to automatically regulate fluid flow within the device.
These components are made by using conventional techniques, and are thus compatible with all other microfluidic components such as mixers, filters and cell culture chambers, said the researchers.
"We've made a versatile control system. We envision that this technology will become a platform for researchers and companies in the microfluidics field to develop sophisticated self-controlled microfluidic devices that automatically process biofluids such as blood and pharmaceuticals for diagnostics or other applications," said Mosadegh.
"Just as the integrated circuit brought the digital information processing power of computers to the people, we envision our microfluidic analog will be able to do the same for cellular and biochemical information," he added.
A paper on the technology is newly published online in Nature Physics.