Drugs are used everyday by people in many different ways for many different reasons. Drug testing has become a standard in pre-employment testing, because of the wide variety of drug use in today's society. Drugs tested for by a possible employer include Cocaine (crack), Amphetamines (crystal), Opiates (codeine, morphine, heroin), PCP (phencyclidine), and Marijuana. Gas chromatography/mass spectrometry is used to test hair and urine samples of possible drug abusers or job applicants, and it is the best method for the testing of drug use. Gas chromatography and mass spectrometry are two different methods for identifying chemical substances, and the two instruments have be coupled together to perform a highly complementary analytical function. The gas chromatograph and the mass spectrometer have theories behind how their techniques work, and specific forensic applications for their instrumentation. The history and theory of the gas chromatography started over forty years ago with the invention of the capillary column. The gas chromatograph offers rapid and very high-res

The idea that a GC/MS produces a fingerprint for a chemical substance makes this instrument a very attractive option when testing for drug identification, and testing people for drug use. Forensic scientists find a drug's identification by using a GC/MS, and use the mass chromatogram in comparison with the test results of another unknown mass chromatogram. If the two mass chromatograms match then the tested chemical substance is that drug it was matched against.

The instrumentation of the gas chromatograph/mass spectrometer is very complex. The instrument's parts include an injector, a carrier gas, a column, a separator, an ionization source, mass separator, and an ion detector. The injector is located on the gas chromatograph and is where the sample gas is injected into the instrument to start the process. The sample gas is then mixed with a carrier gas, which is the mobile phase in gas chromatography. The mixture proceeds into the capillary column where the separation of the sample begins. The capillary column is 15 to 60 meters in length and .25 to .75 millimeters in diameter. Once through the capillary column the now sepa

Some common words found in the essay are:
Marijuana Gas, Spectrometry Drugs, gas chromatograph, chemical substance, gas chromatography, mass chromatogram, mass spectrometer, capillary column, gas chromatograph/mass spectrometer, gas chromatograph mass, chromatograph mass spectrometer, fingerprint chemical substance, hair urine samples, sample gas, urine samples, carrier gas, hair urine,
Approximate Word count = 764
Approximate Pages = 3 (250 words per page double spaced)