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32 CHROMATOGRAPHY


LC tools such as Shimadzu’s tend to be more suited to use in volatile components such as vitamin D


user to separate out individual components and to identify them based on a number of criteria (LRI, retention time, mass spectral matching). “It is unique in its ability to find a match for a component by simply asking a commercially available or research library for a list of possible hits – all done via software control – whereas in times past, the user had to go to an actual paper library.” GC is for more volatile components such as organic acids and steroids, whereas liquid chromatography (LC) is more suited to use in volatile components such as vitamin D, says Parry. Tey are typically used to determine patient levels to identify if there is a condition already present, or if a biomarker can be found to show that a patient may be pre-disposed to a certain condition developing.


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“Established techniques, such as liquid chromatography – mass spectrometry (LCMS) and GCMS are now being replaced with liquid chromatography-tandem mass spectrometry (LCMSMS) and gas chromatography-tandem mass spectrometry (GCMSMS) because the inclusion of the extra MS capacity allows the laboratory to see lower and lower levels, by using the power of the MS units in tandem, but also to increase the accuracy of the result given. MSMS techniques monitor transitions of compounds rather just individual ions, which can lead to the potential for false positives. An example of this would be the use of GCMSMS in the detection of drugs of abuse. Te limits of detection


can be lowered and components can be identified with greater accuracy by using MSMS versus MS alone.” Parry says that Shimadzu


products have grown with the market demand – the need to see lower limits with greater accuracy, and also to separate out greater complex mixtures of components in single analytical runs. Te adaptability of Shimadzu products not only refers to the hardware, but also the reporting software used to allow users greater flexibility in how they can report their findings. Product development is always looking for new ways to make analytical testing an easier, less time consuming and


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