Mass spectrometric quantification of volatile metabolites in breath for noninvasive diagnosis and monitoring of bacterial infection in cystic fibrosis

Abstract:
Research of non-invasive methods for diagnosis and monitoring of bacterial infection in cystic fibrosis is currently a topic of great interest. Hydrogen cyanide has been identified as a breath biomarker of Pseudomonas aeruginosa (PA) infection. However, some trains of PA do not produce HCN. Thus other volatile breath biomarkers are needed order to improve the sensitivity and specificity. We propose to study trace amounts of volatile compounds in breath of CF patients using selected ion flow tube mass spectrometry (SIFT-MS) and gas chromatography mass spectrometry (GC-MS). SIFT-MS quantification of trace gases at low concentrations (10 parts-per-billion by volume, ppbv) will be achieved by reactions of ions H3O+, NO+ and O2+ with the molecules of analyte. Specific objectives are development of methodology for sample collection using thermal desorption tubes for off-line analyses and discovery of breath biomarkers of bacterial infections in patients with cystic fibrosis by quantitative analyses of volatiles in exhaled breath and headspace of sputum and bacterial cultures.