Lab-on-a-chip shows analytical prowess

The Australian Centre for Research on Separation Science (ACROSS) at the University of Tasmania has opened a new million-dollar laboratory to develop and manufacture microfluidics chips capable of analysing samples thousands of times smaller than a drop of water.

Where early microfluidics chips were laser-etched into glass, the proprietary mTas chips are made of plastic, and are stamped with metal templates to create custom-designed networks of microchannels and small wells.

After the sample is introduced into the chip, it is sealed with a transparent top plate, and reagents can be pipetted into the wells.

Under computer control, the chips can purify and analyse biological and other samples using electrophoresis, electro-osmosis, chromatography and other advanced separation techniques, or mixed with chemical or biological reagents. Microelectronics circuits with light-emitting diode readouts can also be incorporated.

ACROSS director Prof Paul Haddad said the chips have two major advantages over laboratory-based analytical techniques. The tiny sample volume means reactions and separation processes run much faster, and a range of analytical processes can be performed serially on a single chip, avoiding the tedious and time-consuming requirement to transfer samples manually between laboratory-based instruments.

"As an example, an average drug testing device takes around 30 minutes to test a sample. With a lab-on-a-chip, that test could take 30 seconds," he said.

Haddad believes the microfluidics chips have 'phenomenal' potential in the clinic, where they could allow doctors to perform blood or urine analyses on the spot. They could be widely applied in forensics, and environmental sampling, where they could be used to analyse samples in the field.

"Current micro-fluidics projects at ACROSS include applications in clinical diagnostics for drug monitoring, advanced separation techniques for complex biological samples and proteomics and analysis of post-blast residues.

"One of the most exciting aspects of a lab-on-a-chip is the potential to create portable or even hand-held devices for on-site use. The forensic possibilities are endless."

In the case of the terrorist attack in Bali, Haddad said the lab-on-a-chip could have given police a six-week start in pursuing the bombers. Instead it took six weeks of painstaking laboratory analysis for explosives experts to identify the type of nitrate fertiliser used in the massive bomb that that destroyed Bali's Sari nightclub in Kuta two years ago.

The new laboratory and clean-room facility will make ACROSS self sufficient in designing and creating microfluidics devices. Master embossing designs will allow basic chip designs to be mass-replicated.