No More Pain: Scientists Develop New Microneedle System for Painless Drug Monitoring

Scientists have developed a microneedle drug monitoring system in hopes of reducing pain during drug measurements and replace expensive blood draws.

Scientists at the University of British Columbia and the Paul Scherrer Institut (PSI) in Switzerland created a new system that consists of half-millimeter long needle-like projections that do not penetrate the patient's skin unlike the standard hypodermic needle.

During medical treatment, the small, thin patch is pressed against the patient's arm to painlessly measure the drugs in the bloodstream without the need for drawing blood.

"Many groups are researching microneedle technology for painless vaccines and drug delivery," Sahan Ranamukhaarachchi from the University of British Columbia, who developed the technology during a research exchange with PSI, said in a press release.

"Using them to painlessly monitor drugs is a newer idea," Ranamukhaarachchi added.

Microneedles are generally painless as they are designed to pierce the outer layer of the skin and not the inner layers, such as the epidermis and the dermis, which contain nerves, blood vessels and active immune cells, the researchers said.

Ranamukhaarachchi and his team created the microneedle system to monitor the antibiotic vancomycin, which is used to treat serious infections and is administered via an intravenous line.

Traditionally, patients taking vancomycin are required to undergo three to four blood draws per day and need to be monitored closely as vancomycin may cause dangerous side effects.

But instead of monitoring vancomycin levels through blood draws, the researchers discovered that a fluid found just beneath the outer layers of the skin could also be used for this purpose. The microneedle is created to collect small amounts (about a millionth of a millimeter) of this fluid, and a reaction occurs within the insides of the microneedle that can be detected with the help of optical sensors, the researchers said. This method allows the researchers to determine the levels of vancomycin in the bloodstream quickly and easily.

"This is probably one of the smallest probe volumes ever recorded for a medically relevant analysis," Urs Hafeli, associate professor of the University of British Columbia's faculty of pharmaceutical sciences, said in a statement.

The technology was described in a paper published in Scientific Reports, and is currently being commercialized by Microdermics Inc.