IntroductionWhen presented with three identical clear and colorless solutions, there are several tools a chemist has at their disposal. Methods of analysing unknown substances can be qualitative or quantitative.
Since qualitative methods are less exact, qualitative analytical techniques are more widely used and widely accepted. These include chromatography and mass spectrometry. Chromatography is This research has many practical applications, such as aquatic toxin identification and forensic science. There is research supporting the coupled use of chromatography and mass spectrometry equipment to provide toxicologists with specific identification of unknown substances (Saint-Marcoux, Lachâtre, and Marquet 2002). However, this method may be overly complex. The method proposed by Little, Williams, Pshenichnov, and Tkachenko (2012) makes use of mass spectrometry measurements and the database called ChemSpider. In order for this method to be viable, the substances in question must be one of the 26 million substances recorded in the database.
This method is supported by Brenton and Godfrey’s research (2012), which notes the accessibility and pitfalls of mass spectrometry, and details methods of enhancing the accuracy of a spectrometer. MethodsUsing sterile equipment, place a sample into the mass spectrometer. Mass spectrometry forms cations from the vaporized compounds it measures within a vacuum. The particles are then given the same kinetic energy, causing them to be deflected when introduced to a magnetic field.
The deflected particles are then measured by the machine, which provides quantitative data about the elements present in the sample. The data output will show the mass to charge ratio of the sample, which will allow the researcher to identify the elements present using the ChemSpider Database. The database will present a list ranging from the most to least likely identity of the compound. The compound should be identified as the one listed first on the database.SourcesGodfrey, A. R.
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; Williams, A. J.; Pshenichnov, A.; Tkachenko, V. Identification of “Known Unknowns” Utilizing Accurate Mass Data and ChemSpider. Journal of The American Society for Mass Spectrometry 2011, 23(1), 179–185.Mceachran, A.
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; Marquet, P. Evaluation of an improved general unknown screening procedure using liquid-Chromatography-Electrospray-Mass spectrometry by comparison with gas chromatography and high-Performance liquid-Chromatography—diode array detection. Journal of the American Society for Mass Spectrometry 2003, 14(1), 14–22.