On-site, handheld DNA analysis

Using lab-on-a-chip technology, James Landers hopes to create a handheld device that may eventually allow users to quickly and inexpensively conduct DNA tests from almost anywhere, without need for a complex and expensive central laboratory.

"We are simplifying and miniaturising the analytical processes so we can do this work in the field, away from traditional laboratories, with very fast analysis times, and at a greatly reduced cost," said Landers, a University of Virginia professor of chemistry and mechanical engineering and associate professor of pathology.

Landers published a review this month of his research and the emerging field of lab-on-a-chip technology in the journal Analytical Chemistry.

"This area of research has matured enough during the last five years to allow us to seriously consider future possibilities for devices that would allow sample-in, answer-out capabilities from almost anywhere," he said.

Landers and a team of researchers at U.Va., including mechanical and electrical engineers, with input from pathologists and physicians, are designing a handheld device — based on a unit the size of a microscope slide — that houses many of the analytical tools of an entire laboratory, in extreme miniature. The unit can test, for example, a pin-prick-size droplet of blood, and within an hour provide a DNA analysis.

"In creating these automated micro-fluidic devices, we can now begin to do macro-chemistry at the microscale," Landers said.

Such a device could be used in a doctor's office, for example, to quickly test for an array of infectious diseases, such as anthrax, avian flu or HIV, as well as for cancer or genetic defects. Because of the quick turnaround time, a patient would be able to wait only a short time on site for a diagnosis. Appropriate treatment, if needed, could begin immediately.

Currently, test tube-size fluid samples are sent to external labs for analysis, usually requiring a 24- to 48-hour wait for a result.

"Time is of the essence when dealing with an infectious disease such as meningitis," Landers said. "We can greatly reduce that test time, and reduce the anxiety a patient experiences while waiting."

Landers said the research also dovetails with the trend towards personalised medicine, in which medical care is increasingly tailored to the specific genetic profile of a patient. Such highly specialised personalised care can allow physicians to develop specific therapies for patients who might be susceptible to, for example, particular types of cancers.