Mass Spectrometric Profiling of Low-Molecular-Weight Volatile Compounds - Diagnostic Potential and Latest Applications

Abstract

The theoretical use of mass spectrometric profiling of low-molecular-weight volatile compounds, as one possible method to non-invasively and rapidly diagnose a variety of diseases, such as cancer, infection, and metabolic disorders has greatly raised the profile of this technique over the last ten years. Despite a number of promising results, this technique has not been introduced into common clinical practice yet. The use of mass spectrometric profiling of exhaled air is particularly hampered by various technical problems and basic methodological issues which have only been partially overcome. However, breath analysis aside, recently published studies reveal completely new ideas and concepts on how to establish fast and reliable diagnosis by using this valuable tool. These studies focussed on the headspace screening of various bodily fluids and sample fluids obtained during diagnostic procedures, as well as microbial cell cultures and demonstrated the vast diagnostic potential of this technique in a wide variety of settings, predominantly in vitro. It is the aim of the present review to discuss the most commonly detected low-molecular-weight volatile compounds and to summarize the current potential applications, latest developments and future perspectives of this promising diagnostic approach.

Urinary Volatile Compounds as Biomarkers for Lung Cancer: A Proof of Principle Study Using Odor Signatures in Mouse Models of Lung Cancer

“…More importantly, we were able to mimic this ability using bioanalytic techniques. This suggests it will be possible to create a biomimetic sensor based on the knowledge of olfactory system for screening diagnostic odorants that could be practical for widespread applications [27], [28], [29], [30]. Indeed, genetically engineered yeast expressing an olfactory receptor and its signal transduction system have been shown to be capable of detecting 2,4-dinitrotoluene, a compound diagnostic of explosives [31].…”

Gut Microbiota Profiling: Metabolomics Based Approach to Unravel Compounds Affecting Human Health

“…Hence, the rising acceptance of the gut microbiota involvement in the pathogenesis of IBD has led to the use of fecal matrix as a sample to determine metabolite profiling (Walton et al, 2013 ). Indeed, specific microbial VOCs profiles can provide specific biomarker candidates for diagnostic purposes (Schöller et al, 1997 ; Lechner and Rieder, 2007 ; Bunge et al, 2008 ).…”

Detection of volatile organic compounds in cattle naturally infected with Mycobacterium bovis

“…In disease formation, both host and invading cells can undergo structural changes, one example of which would be oxidative stress, i.e., a peroxidation of the cell membrane that causes VOCs to be emitted [16]. Some of these VOCs appear in distinctively different mixture compositions [17][18][19][20][21][22]. What is particularly significant about this approach is that each type of disease has its own unique pattern of VOCs; therefore, the presence of one disease would not mask other disease types [23].…”

“…What is particularly significant about this approach is that each type of disease has its own unique pattern of VOCs; therefore, the presence of one disease would not mask other disease types [23]. These VOCs can be detected directly from: (i) cultured cells (i.e., the mixture of VOCs trapped above the cells in a sealed vessel) [20][21][22]; (ii) urine [24]; or (iii) exhaled breath [17][18][19].…”