Rapid communications in mass spectrometry : RCM
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Rapid Commun. Mass Spectrom. · Jan 2002
Liquid chromatography/mass spectrometric bioanalysis of a modified gamma-cyclodextrin (Org 25969) and Rocuronium bromide (Org 9426) in guinea pig plasma and urine: its application to determine the plasma pharmacokinetics of Org 25969.
A sensitive and specific liquid chromatography/mass spectrometry (LC/MS) method has been developed and validated for the quantification of the modified gamma-cyclodextrin Org 25969 and Rocuronium bromide (Roc or Org 9426) in the plasma and urine of guinea pigs. The assay was linear and reproducible over the range 25-10000 ng/mL for both compounds. The lowest limit of quantification (LLOQ) for both compounds in urine was 25 ng/mL. ⋯ The LC/MS analyses of Org 25969 and Org 9426 were performed using two different assay conditions. It was not possible to quantify the complex of cyclodextrin and Roc as it dissociated on the LC column. The use of LC/MS conferred great advantage to the quantification of both Org 25969 and Org 9426, as they were not chromogenic enough to afford the sensitivity and specificity required for the assay.
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Rapid Commun. Mass Spectrom. · Jan 2002
Analysis of petrol and diesel vapour and vehicle engine exhaust gases using selected ion flow tube mass spectrometry.
We have used selected ion flow tube mass spectrometry (SIFT-MS) to analyse the vapours emitted by petrol and diesel fuels and the exhaust gases from petrol (spark ignition) and diesel (compression ignition) engine vehicles fitted with catalytic converters. Only those components of these media that have significant vapour pressures at ambient temperatures were analysed and thus particulates were obviously not detected. These media have been analysed using the full scope of SIFT-MS, i.e., with the three available precursor ions H3O+, NO+ and O2+. ⋯ These data were obtained from samples collected into pre-evacuated stainless steel vessels. Trapping of the volatile compounds from the gas samples is not required and analysis was completed a few minutes later. All the above compounds are detected simultaneously, which demonstrates the value of SIFT-MS in this area of research.
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Rapid Commun. Mass Spectrom. · Jan 2002
Selected ion flow tube studies of the reactions of H3O+, NO+ and O2+ with the anaesthetic gases halothane, isoflurane and sevoflurane.
We have carried out a study of the reactions of H(3)O(+), NO(+) and O(2) (+), the commonly used precursor ions for selected ion flow tube mass spectrometry (SIFT-MS), with three anaesthetic gases, halothane, isoflurane and sevoflurane. The motivation for this study was to provide the necessary kinetic data that would allow the quantification of these anaesthetic gases in operating theatre air and in the breath of theatre staff and post-operative patients. A clear negative result from these experiments is that NO(+), although undergoing the simplest chemistry, is unsuitable for this SIFT-MS application. ⋯ The detailed ion chemistry is discussed and the specific monitor ions are indicated. Hence, the feasibility of on-line breath monitoring is demonstrated by simple examples. These studies have opened the way to measurements in the clinical environment.