– Researchers find microneedle biosensors can be used to monitor the changing concentration of antibiotics in a patient’s system.
– Findings published in The Lancet Digital Health, show the sensors enable real-time monitoring of changes in antibiotic concentration in the body, with similar results to those obtained from blood tests.
Small, non-invasive patches worn on the skin can accurately detect the levels of medication in a patient’s system, matching the accuracy of current clinical methods, according to key findings from a small-scale clinical evaluation. Researchers at Imperial College London published their findings in The Lancet Digital Health, illustrating for the first time how microneedle biosensors enable real-time monitoring of changes in antibiotic concentration in the body, with similar results to those obtained from blood tests.
What Are Microneedle Biosensors?
Microneedle biosensors use a series of microscopic ‘teeth’ to penetrate the skin and detect changes in the fluid between cells. These teeth act as electrodes to detect changes in pH and can be coated with enzymes which react with a drug of choice, altering the local pH of the surrounding tissue if the drug is present.
Previously, the technology has been used for continuous monitoring of blood sugar, but the Imperial group has, for the first time, showing its potential for use in monitoring changes to drug concentrations. The technology was developed through research supported by funding from the National Institute for Health Research (NIHR) and Fondation Merieux.
Study Background & Protocols
Led by Dr. Timothy Rawson, the Imperial team of researchers conducted at a small proof-of-concept trial of the biosensors in 10 healthy patients who were given doses of penicillin. Between April and August 2018, volunteers were recruited and treated at the NIHR Imperial Biomedical Research Centre at Imperial College Healthcare NHS Trust. Sensor patches (1.5 cm sq) were placed on their forearms and connected to monitors, with measurements taken frequently – from 30 minutes before receiving oral penicillin, to four hours afterward. Blood samples were taken at the same time points for comparison.
Data collected from nine patients revealed that the sensors could accurately detect the changing concentration of penicillin in patients’ bodies. The researchers found that while penicillin concentrations varied widely from patient to patient, the overall readings from the biosensors were similar to those from blood samples – showing a marked decrease in drug concentration over time.
The early findings are positive, but they explain the study is limited by the very small sample size and the was only tested on a single antibiotic, in healthy patients. Due to the small sample size, the researchers plan to conduct further testing in larger patient groups to strengthen the initial findings. In addition, they will test how the biosensors could help optimize the dosing of penicillin and other similar antibiotics.
They add that the biosensors could form the basis of a ‘closed-loop system’, like an insulin pump – where antibiotics are administered to patients and levels continuously monitored to ensure they receive a sufficient dose.
Technology Could Transform How Patients With Serious Infections Are Treated
The team believes the technology could change how patients with serious infections are treated by showing how quickly their bodies ‘use up’ medications they are given. The researchers add that if future development and testing proves successful and the technology reaches the clinic, it could help to cut costs for the NHS, reduce drug-resistant infections and improve treatment for patients with life-threatening infections and improve the management of less serious ones.
They add that biosensors could reduce the need for blood sampling and analysis as well as offer more efficient, personalized drug delivery that could potentially be delivered outside of the hospital setting for outpatients.
“Microneedle biosensors hold a great potential for monitoring and treating the sickest of patients. When patients in hospital are treated for severe bacterial infections the only way we have of seeing whether antibiotics we give them are working is to wait and see how they respond, and to take frequent blood samples to analyse levels of the drugs in their system – but this can take time, said Dr Timothy Rawson, from Imperial’s Department of Infectious Disease.
“Our biosensors could help to change that. By using a simple patch on the skin of the arm, or potentially at the site of infection, it could tell us how much of a drug is being used by the body and provide us with vital medical information, in real-time,” added Rawson.
This collaborative work will be advanced further through Imperial’s National Centre for Antimicrobial Research and Optimisation (CAMO)