Title: | Sensitivity enhancement in the determination of volatile biomarkers in saliva using a mass spectrometry-based electronic nose with a programmed temperature vaporizer |
Author(s): | del Nogal Sanchez M; Callejo Gomez PA; Perez Pavon JL; Moreno Cordero B; Crisolino Pozas AP; Sanchez Rodriguez A; |
Address: | "Departamento de Quimica Analitica, Nutricion y Bromatologia, Facultad de Ciencias Quimicas, Universidad de Salamanca , 37008 Salamanca, Spain" |
ISSN/ISBN: | 1520-6882 (Electronic) 0003-2700 (Linking) |
Abstract: | "With a view to improving the sensitivity of direct coupling of a headspace sampler (HS) with a mass spectrometer (MS), here we propose the use of a programmed temperature vaporizer (PTV) in solvent-vent injection mode before the sample is introduced into the MS. This preconcentration scheme has been used for some time in many methods based on gas chromatography (GC), but to the best of our knowledge it has not yet been used in an electronic nose based on MS. The increase in the S/N ratio with the proposed instrumental configuration (HS-PTV/MS) lies between 6.9- and 22-fold. The main advantage of using this injector lies in the fact that it does not involve time-consuming steps. To check the possibilities of this methodology, saliva samples from healthy volunteers and patients with different types of illnesses (including some types of cancer) were analyzed. None of the compounds studied was detected in the samples corresponding to the healthy volunteers. One or more biomarkers, at levels ranging from 13 to 500 mug/L, were found in five of the samples from the patients. Additionally, separative analysis by HS-PTV-GC/MS was performed for confirmatory purposes and both methods provided similar results. The main advantage of the proposed methodology is that no prior chromatographic separation and no sample manipulation are required" |
Keywords: | Biomarkers/*analysis *Electronics Gas Chromatography-Mass Spectrometry/*methods Hot Temperature Limit of Detection Saliva/*chemistry Volatile Organic Compounds/*analysis; |
Notes: | "Medlinedel Nogal Sanchez, Miguel Callejo Gomez, Pedro Angel Perez Pavon, Jose Luis Moreno Cordero, Bernardo Crisolino Pozas, Angel Pedro Sanchez Rodriguez, Angel eng Research Support, Non-U.S. Gov't 2014/07/06 Anal Chem. 2014 Aug 5; 86(15):7890-8. doi: 10.1021/ac501917a. Epub 2014 Jul 11" |