Photo courtesy of
Sahan Ranamukhaarachchi
A new microneedle drug monitoring system could one day replace invasive blood draws, according to researchers.
The system consists of a small, thin patch that is pressed against a patient’s arm during medical treatment and measures drugs in the bloodstream painlessly without drawing any blood.
The tiny projections on this patch resemble hollow cones and don’t pierce the skin like a standard hypodermic needle.
The researchers described this system in Scientific Reports.
“Many groups are researching microneedle technology for painless vaccines and drug delivery,” said study author Sahan Ranamukhaarachchi, a PhD student at the University of British Columbia (UBC) in Vancouver, British Columbia, Canada. “Using them to painlessly monitor drugs is a newer idea.”
The microneedle system Ranamukhaarachchi and his colleagues created was developed to monitor the antibiotic vancomycin. Patients taking vancomycin must be closely monitored because the drug can cause life-threatening side effects, so the patients undergo 3 to 4 blood draws per day.
The researchers discovered they could use fluid found just below the outer layer of skin, instead of blood, to monitor levels of vancomycin in the bloodstream.
The microneedle patch collects a tiny amount of the fluid, less than 1 nL, and a reaction occurs on the inside of the microneedles that can be detected using an optical sensor. This allows the user to quickly determine the concentration of vancomycin.
“This is probably one of the smallest probe volumes ever recorded for a medically relevant analysis,” said study author Urs Häfeli, PhD, of UBC.
This microneedle drug monitoring system was developed out of a research collaboration between Dr Häfeli and Boris Stoeber, PhD, also of UBC. The system is being commercialized by the UBC spin-off Microdermics Inc.
