Engineers and physicians at the University of California, Davis, have developed a breath test that can detect opioid drugs in the exhaled air.
Opioids pertain to a class of drugs, generally used for pain relief. The new technology can help monitor the drug intake in patients suffering from chronic pain, and also help prevent drug abuse. According to Professor Cristina Davis, chair of the department of Mechanical and Aerospace Engineering at UC Davis, “There are a few ways we think this could impact society”.
Breath testing can provide a reliable and non-invasive substitute for blood tests when examining for drugs in the system. Monitoring of drugs and their metabolites in patients prescribed with opioids and other analgesic drugs is vital to ensure the subjects are “taking their medicine correctly, the prescribed drugs are being metabolized properly and they are not taking any confounding medication”.
The test, devised by postdoctoral researcher, Eva Borras and her team, includes taking breath samples from patients. Water droplets in the sample are condensed and frozen to analyze the contents using mass spectrometry.
The study consisted of a small group of patients who were asked to breathe normally for 15 minutes, into a glass tube surrounded by dry ice. The water droplets in the exhaled breath condensed and were frozen for further testing. The Exhaled Breath Condensate (EBC) was retrieved from the tube and the glass container was subjected to an ethanol wash – to make sure all of the EBC was extracted.
The sample was analyzed using liquid chromatography and mass spectrometry to identify the metabolites and their quantities present in the breath sample.
The test also included blood samples – taken immediately after the condensate collection, offering a fair comparison between the opioids and their metabolites in the blood and in the breath of the patient, at the moment. According to Davis, “We can see both the original drug and metabolites in exhaled breath”.
The researchers successfully identified the drugs in the exhaled breath, even though, in small amounts. They also found a positive correlation between concentrations of some of the main opioids in the blood and the exhaled air.
Although, the results were successful, the small-scale study cannot fully validate the technology and needs a larger sample size for testing. Davis and her team is now working towards real-time bedside testing and developing a device that can be even more accurate in drug detection.
The research was funded by grants from the UC Davis Medical Center’s Collaborative for Diagnostic Innovation, the U.S. Department of Energy and the NIH.