This week researchers from the American Chemical Society are reporting the development of a backpack-sized device that can perform highly accurate and sensitive tests for cocaine and other drugs of abuse onsite and within a few minutes. Testing for cocaine and other drugs usually involves two steps: a quick on site prescreen, and then a more accurate confirmatory test at a distant laboratory. This process can take days or weeks. The study, which appears in ACS' journal Analytical Chemistry, provides an alternative to the current approach.
The research team put together a compact system that can perform all necessary steps, extracting drugs of abuse from urine with a microfluidic device coupled to a small mass spectrometer that can identify the substances. A custom digital microfluidic system was designed to deliver droplets of solvent to dried urine samples and then transport extracted analytes to an array of nanoelectrospray emitters for analysis. The backpack-sized instrument can analyze cocaine, benzoylecgonine (a metabolite of cocaine), and codeine in four samples in less than 15 minutes. The amount of cocaine it can detect is compatible with limits set by the United Nations Office on Drugs and Crime. The researchers say the device could be used for many different kinds of tests in which laboratory-quality results are needed quickly.
The current two-stage system of testing urine for drugs of abuse is expensive and time-consuming. The ideal solution, researchers say, is to skip the prescreening step and instead bring the lab to the site, but in an easy-to-use, portable package. Currently, when samples arrive at labs for confirmation testing, trained technicians use a “gold standard” method, relying on sample processing, liquid chromatography, and mass spectrometry to analyze them. Small versions of instruments that implement these techniques can provide results at or near lab-quality, but they haven't been optimized and tested together as a single, portable instrument until now. Read the study abstract.
Read more
