For some diagnostic tests, drawing blood by syringe could someday be replaced by a simple skin patch.Kuebi = Armin Kübelbeck, Wikimedia CommonsSimon R. Corrie and colleagues note that while blood is rich with molecular clues that tell a story about a person's health, withdrawing it is often painful. It also requires trained personnel and expensive lab equipment and facilities for analysis. These factors don't lend themselves to patient compliance or accessibility in resource-limited places. Scientists have been trying to address these hurdles by developing diagnostic patches that are covered on one side with thousands of microscopic, hollow needles that can sample fluid in the skin. But so far, these devices have only been able to test for one compound at a time. However, many diseases can be diagnosed more reliably by detecting multiple biomarkers. Corrie's team wanted to design a new patch that could meet this need.

The researchers optimized their device so it could capture two biomarkers for the malaria parasite, Plasmodium falciparum, which kills more than 1 million people every year. To test it, they injected malaria proteins into the bloodstream of live mice and applied the patch to their skin. The patch successfully captured the proteins in the skin tissue. Such devices, they conclude, could be used in the future to diagnose malaria and other infectious diseases in a less painful way.

The authors acknowledge funding from the Australian Research Council and the Australian Infectious Diseases Research Centre.