The Detection Of Acetonitrile In Human Breath By Extractive Electrospray Ionization Mass Spectrometry

Breath analysis by virtue of its potential medical research value, and as a non-invasivesample, simple sampling and continuous available is of interest for modern clinicaldiagnosis and metabonomics. The concentration levels of acetonitrile, an importantbiomarker in human exhaled gas, are correlated with human health. This paper introducesphysical and chemical properties of acetonitrile; reviews detection methods of actonitrile inanalytical science and important application values of mass spectrometry in breath analysis.And researchs the application of extractive electrospraying ionization mass spectrometry indetection of acetonitrile in human exhaled breath. Then, established a novel platform fordirect and indirect detection of acetonitrile, and applying these methods to studymetabonomics and clinical diagnosis.The main research content of this thesis involves as following:1) The important value of breath detection and acetonitrile in human breath detectionare descriped. Reviews the mechanism, advantages and disadvantages of the methods thatused for detect acetonitrile in human exhaled breath. Indroduces the mechanism andapplication value of extractive electrospray ionization mass spectrometry in human exhaledbreath analysis.2) Herein we constructed a novel platform of EESI-MS for direct, rapid, on-linedetect of acetonitrile in human breath without any sample pretreatment. Under theoptimized working conditions, the quantitative information of acetonitrile in human breathis acquired effectively. For acetonitrile, a limit of detection was found to be5.71pL/L. Ourresults prove that EESI-Ion Trap MS is a powerful analytical platform to provide highsensitivity, high precision, rapid analysis and high specificity for semi-quantitativeanalysis of acetonitrile in human breath, and for detection of other bio-molecules inexhaled breath potentially. And for acetonitrile in breath, in order to reveal the generation mechanism of acetonitrile in breath, the concentration and degradation of actetonitrile inthe breath of healthy volunteers that before/after meal, yin-yang deficiency patients, peoplethat before/after smoking, and passive smokers were also studied. Thus, EESI-MS is apractical and convenient tool for metabolomics and clinical medicine study.3) Built a method, using methonal as the sovent of acetonitrile in exhaled breath, toselectively off-line detect of acetonitrile based on EESI-MS without complicated samplecollection and pretreatment. Then, under the optimized conditions, the body’s metabolicchanges after smoking can be observed using this off-line method. Just few minutes arerequired to acquire detection results. The results show the potiential application to off-linestudy other bio-marker in breath, on account of quickly analysis, briefly operate, and easilyaccepted by subject.4) Summary these analytical method and its applications, and put forward someimproving suggestions according the problems meet in pratical detection. So EESI-MS canefficiently detect bio-markers in exhaled breath and has broad application prospects inmodern mass spectrometry.