Blood sampling procedures to monitor and optimize antibiotic doses may soon be replaced by a minimally invasive, microneedle array biosensor. The accuracy of the sensor measurements is comparable to those of blood tests, and use of the device could prove valuable in preventing drug toxicity and Enzyme-coated microneedles penetrate the skin. Source: Imperial College Londonantimicrobial resistance.

As the sensor patch is placed on a patient’s skin, enzyme-coated electrode needles penetrate the outermost layer. If the targeted antibiotic is present in the interstitial fluid between skin cells, which is indicative of levels in the bloodstream, the enzymes react with the drug and alter the fluid’s pH level. An external monitor connected to the patch displays the concentration of antibiotics as reflected by pH.

Tests with volunteers demonstrated that the microneedle biosensor patches accurately measured levels of orally-administered penicillin. The readings matched those of blood samples and documented a decline in drug concentrations with time.

This proof of concept study, conducted by researchers from Imperial College London and Swansea University, will be followed by assessments of microneedle use in larger patient cohorts and possible inclusion of the device in closed-loop control systems for automated drug delivery.