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Article Summary

GC-MS Drug Testing: How It Works and the Limitations

The GC-MS drug testing unit, which combines the gas chromatograph technology and the mass spectrometer technology, is on the brink of being a perfect drug test that is done in an automated machine. The GC and the MS technologies are combined to identify and enumerate the presence of particular drugs and metabolites in a sample. Incidentally, GC-MS is commonly regarded as the 'gold standard' to carry out a specific test.

People who regularly depend on the results of drug testing are mostly unacquainted with the problems inherent in the tests. Should the drug tests be used in a holistic instructive context, with additional signs of abuse taken into consideration, they can be more helpful. The best way to understand the GC-MS drug testing is to learn how it works.

How it works

The GC-MS as mentioned earlier is a blend of two technologies and the machine does two tests, as the name suggests. The gas chromatograph (GS) is usually a device for sorting out and positively identifying compounds depending on their relative adhesion to a substrate material known as an adsorbent. The adsorbent is typically alumina gel or silica lining in column within the computerized machine. The test sample is infused into a flow of carrier gas within the machine and it passes the column that is heated with an oven.

Once separation is complete the materials then go through the MS, mass spectrometer. Here, the materials are shattered in the existence of a well-built magnetic field. Remains of the materials are subsequently analyzed in relation to their molecular mass. The results are contrasted against databases that are based on the statistical probability of specific compounds to disintegrate in specific ways.

Basically, the GC-Ms drug testing unit converts the sample into a gas, channels the gas into a small tube, and scrutinizes the way the gas components group themselves inside the tube. If a properly certified GC-MS unit is used to test a sample of urine from an identified drug abuser, it evaluates the cocaine, adulterants, THC, methamphetamine and amphetamine and then indicates how much each of these drugs was found in the sample.

Limitations of GC-MS drug testing

There are some problems with GC-MS drug testing. Firstly, the machine is outrageously costly and so is the operator. For instance a second-hand GC-MS could cost up to $50,000 with a new one going for more than $75,000. This is just for a tabletop that can test only a small number of samples per hour. The machines used by large laboratories are worth some million dollars. These can be used to test about a thousand samples in a day and they are set up to operate many test protocols.

Another limitation is that false positives results for opiates tests are common in individuals taking some kinds of antibiotics since the drug laboratories do not consider the cause of false positives. Individuals taking ofloxacin and levofloxicin are often given false positive outcomes several times in drug tests due to the disintegration patterns of antibiotics forcing the software to automatically pick the most likely match in found in the database.

In addition, there are no laboratories presently running outside of educational settings, which have GC-MS drug testing operated by engineers and chemists with adequate experience to evaluate unfamiliar compounds. It takes at least four years of analytical chemistry degree and a minimum of two years of training in toxicology so as to attain the experience necessary to process pharmaceutical unknowns through GC-MS drug testing unit.

Drug labs are normally operated by technicians who are directed by an engineer or chemist holding a BS degree. Given that these staff is well trained to handle regular compounds in the databases, there should not be any difficulty as to the likelihood of false positive results emerging from such settings. A certain air of mystery has arisen regarding the GC-MS drug testing amongst drug test providers and worker supervisors. The widespread certainty in the perfectness of the GC-MS is thus unjustified.

There are a number of different types of drug testing and GC-MS is one method that is not easy to beat. For a reliable test using the GC-MS drug testing unit, there are certain aspects that people should look for, which include strict collection procedures, random notification and proper testing procedures.

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