Hydrochloric acid 48 Mass spectrometer

Pd removal was determined as follows. An aliquot of a representative liquid or solid sample was accurately weighed and subsequently digested by refluxing in nitric and/or hydrochloric acid using a closed vessel microwave procedure (CEM MARS5 Xpress or Milestone Ethos EZ). Cooled, digested samples were diluted, matrix matched to standards, and referenced to a linear calibration curve for quantitation an internal standard was employed to improve quantitation. All samples were analyzed by an Inductively Coupled Plasma Mass Spectrometer or ICP/MS (Perkin Elmer SCIEX Elan DRCII) operated in the standard mode. 

The principal advantages of gas chromatographic methods over ion exchange methods are that Isomers of most amino acids may be determined in a single chromatographic step and the analysis time is much shorter. Furthermore, it is possible to couple an optically active column in the gas chromatograph to a mass spectrometer which allows analysis of incompletely separated peaks and correction of the results for racemlzation that may occur during acid hydrolysis of the protein sample when deuterium chloride is used for hydrolysis Instead of hydrochloric acid (39). 

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