Miniaturisation Takes DNA Testing from Cumbersome Machines to Portable Lab on a Chip Technology

Researchers in Hong Kong have miniaturized technology needed to perform the versatile polymerase chain reaction (PCR) - widely used in criminal investigations, disease diagnosis, and a range of other key applications. In a study scheduled for the Jan. 15 issue of ACS’ Analytical Chemistry, a semi-monthly journal, they report development of a long-sought PCR microchip that could permit use of PCR at crime scenes, in doctors’ offices, and other out-of-lab locations.

I-Ming Hsing and colleagues note that PCR works like a biological copy machine, transforming a few wisps of DNA into billions of copies. However, existing PCR machines are so big and complex that they can be used only in laboratories. Scientists have searched for years for a portable, PCR technique that can be used outside the lab.

The study describes a new PCR technique that uses electrochemical DNA sensors to provide simultaneous DNA amplification and detection on a silicon-glass microchip. Their performance tests show that the new technique, called electrochemical real-time PCR (ERT-PCR), is about as fast and sensitive as conventional PCR. The new technique shows “tremendous” promise as a portable system for moving DNA analysis out of the lab and into remote locations, the researchers say.