Genetic risk lab test utilises nanotechnology

A new miniature biosensing laboratory device, which applies the benefits of micro- and nanotechnology, has been developed, which processes a patient's DNA indicating whether they are at risk of diseases, such as cancer.

It's another step in the nanotechnology revolution that has seen it take a hold on everything from drug delivery to therapeutic applications, revolving around the idea of miniaturisation as a faster way of doing things.

The Optonanogen project, with support from the EU, aims to develop a system, which detect mutations of the BRCA1 gene responsible for between 2.5 and 5 per cent of the incidences of breast cancer in women.

Such is the potential in this technology, the project hopes to develop tests that can be used to detect virtually any genetic anomaly, as well as proteins linked to viruses, chemical contamination in food or water pollution.

"There are a broad variety of applications for this system, although the main market is in biomedicine," explains Optonanogen coordinator Laura Lechuga at the National Microelectronics Centre (CNM) in Spain.

"Although commercial biosensing systems exist, they are bulkier and designed for use in laboratories. This Information Society Technologies project is the first to develop a fully integrated system on a smaller, more portable scale in this field," she added.

It currently takes hours or even days to carry out this kind of analysis in a laboratory, which is generally only used to test high-risk groups, such as women with a family history of breast cancer.

The final device will be roughly the size of a human hand, allowing it to be used in doctors' surgeries to determine the genetic predisposition of a patient to certain diseases in a matter of minutes.

To detect genetic mutations the Optonanogen system uses nucleic-acid-coated array of 20 microcantilevers that react when they come into contact with a DNA sample, displaying the genetic irregularity.

A microfluidic header is used to inject the sample into the device and the deflection of the cantilevers - by as little as 0.1 to 0.5 nanometres - is picked up by a photo-detector array based on the reflection of light off the cantilevers from special laser technology

"We've patented both the microcantilever set up and the optical detection system," Lechuga commented. "We are due to take out a third patent on the microfluidic header, which is unique in that it uses individual inlet and outlet paths for each cantilever rather than one for the whole array."

The cantilever array and microfluidic header are due to be low-cost components that would be disposable if used for medical analysis but which could be cleansed and reused for other applications.

After evaluation trials later this year, a commercial variant of the system is likely to be produced within two years by Sensia, a recently formed spin-off company from the CNM.