An ultrasensitive test for performance-enhancing drugs

Researchers have developed a new way to detect performance-enhancing drugs (PEDs), said to be 1000 times more sensitive than current methods. The technique was presented at the 247th National Meeting & Exposition of the American Chemical Society (ACS).

“How much of a drug someone took or how long ago they took it are beyond the analyst’s control,” said Dr Daniel Armstrong of the University of Texas at Arlington. “The only thing you can control is how sensitive your method is. Our goal is to develop ultrasensitive methods that will extend the window of detection, and we have maybe the most sensitive method in the world.”

Hongyue Guo, a graduate student in Dr Armstrong’s lab, explained that the new strategy is a simple variation on mass spectrometry (MS), a technique routinely used by The International Olympic Committee, the US Anti-Doping Agency and more. MS separates compounds by mass, allowing scientists to determine the component parts of a mixture. In the case of PEDs, technicians use the method to find the metabolites left over in blood, urine or other body fluids after the body breaks the doping agents down.

Because some of the metabolites are small and have a negative charge, they may not produce a signal strong enough for the instrument to detect, Dr Armstrong explained - especially in the case of stimulants, which the body rapidly breaks down. Dr Armstrong and his team have developed paired ion electrospray ionisation (PIESI), which gathers several of the metabolites together and thus makes them more obvious to the detector.

So far, Guo has used PIESI to detect different kinds of steroids and stimulants, as well as alcohol. He has demonstrated that the technique is often sensitive enough to detect one part per billion of the PED metabolite in urine, which he said is up to 1000 times better than existing methods.

Dr Armstrong noted that the test will be useful in other applications as well. It is already being used to detect compounds crucial to human health such as phospholipids and pesticides and herbicides, as well as other environmental pollutants. In some cases, he said, PIESI is 100,000 times more sensitive than other detection methods.

Furthermore, said Guo, testing laboratories won’t need to purchase any new equipment. PIESI only requires adding one ingredient to existing MS procedures - a chemical which is already commercially available and inexpensive.