Tiny wonders

The future is big for small diagnostic devices

As a corollary to the saying “the bigger they are, the harder they fall,” one Tufts professor believes that the “the smaller they are, the more effectively they can diagnose.” According to David Walt, Robinson Professor of Chemistry, a new breed of tiny, inexpensive medical diagnostic devices is showing great promise and ultimately could change the way patients get medical care.

David Walt © MARK MORELLI

“We are moving toward a time in the not-too-distant future when we really will be able to conduct thousands or hundreds of thousands of tests in a small, inexpensive device,” Walt told American Medical News, a publication of the American Medical Association.

Despite their compact size, these devices are powerful. They are already commonly found in breathalyzers deployed by police and in pocket-sized test equipment used for checking glucose levels in diabetic patients. The technology also has been adapted for capsule colonoscopy, which can detect gastrointestinal bleeding and transmit pictures from inside a patient’s intestinal tract, and for DNA microarrays that contain the known extent of the human genome.

In an article that appeared in Nature last April, Walt touted the therapeutic value of these systems while also noting the dramatic changes they are apt to bring to patient care. “As is common for medical and clinical diagnostic systems, several regulatory issues must be resolved before miniaturized diagnostic technologies become approved and accepted,” he wrote. “In particular, the vast amount of data that can be collected on a single patient sample using arrays presents a challenge to regulatory agencies and clinicians alike.”

Another change would be the kind of samples that doctors will need to gather from patients. As one example, Walt cited a new type of saliva-based HIV test that takes just 20 minutes to complete. Eventually, he says, the technology may provide “personalized health care with diagnosis and disease-monitoring occurring in the home with easy-to-use miniature devices.”

Efficiency will be one benefit of the trend. “In the future, we will be able to measure everything all of the time because it won’t make any sense to measure one thing when you can measure all things for the same price,” Walt told the News.