WADA’s analytical techniques
of King ’s College London, head of the United Kingdom’s WADA - accredited laboratory, tells me that ‘ drugs are already routinely being tested for at low ng/mL or pg/mL concentrations in urine ’ . 5 A nanogram per millilitre concentration means that the substances are being tested at the level of a billionth of a gram for each millilitre of urine, and this means that even the smallest amount of a performance-enhancing drug could be detected. The majority of tests used to identify substances in an athlete’s urine use gas chromatography in conjunction with mass
Figure 1: Diagram of a Gas Chromatograph
spectrometry, hence figuring out the exact chemical coordination of the substances used. Gas chromatography is an analytical technique that can identify substances that can be vaporized (converted into a gaseous form) without the substance decomposing. The vaporized gas is moved into the chromatography without reacting by being placed in a carrier gas, which is an inert gas (one that is very unreactive, such as helium), in a process called the mobile phase. The substances and the inert gas travel to the stationary phase, which is a microscopic layer of liquid or polymer inside a metal tubing called the column. The vaporized urine samples are sent towards the column and elute through the stationary phase. Elution is a process in which different compounds pass through the stationary phase at different speeds due to various chemical structures and their abilities to be adsorbed by the stationary phase. This means all the different urine samples can be separated from each other, meaning they can pass a mass spectrometer at different times and hence be identified separately. 6 Although gas chromatography is very effective at separating substances when used with mass spectrometry, it is limited to substances that are very volatile, and hence other drugs may not pass through the gas chromatograph easily. Gas chromatography is used in conjunction with mass spectrometry, which is a very important analytical technique. In mass spectrometry, the gaseous compounds are bombarded with high energy electrons to create positive ions of the same substance, then are accelerated by charged plates in order to pass a magnetic field. Owing to the various masses of the positive ions, each substance deflects the magnetic field at a different projection and will meet an analytical device at a different point – identifying the relative masses of the different substances. With complex organic molecules, the bombardment phase may break up some of the bonds and create molar fragments. Owing to the different breakages that could happen, there will be different readings on the same mass spectrometer, with fragments of different intensities. This is useful, however, since we can find out the total molarmass of the substance (by finding the last major peak on the spectrometer reading) andwork out the structural formula. 7 Therefore, one can tell how that in conjunction with gas chromatography, mass spectrometry is able to actively analyse and detect substances in a test for performance-enhancing drugs. As WADA increasingly gets large funding from government agencies, more money can be invested in continuing to develop these state-of-the-art techniques in order to detect and prevent the use of performance-enhancing drugs in sport.
Although the technologies being used in the tests for performance-enhancing drugs continue to develop, much stress has been placed on the actual list of banned substances which claim to enhance
5 Brailsford 2019. 6 UCLA 2016. 7 Curtis 2015.
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