The detection of airborne gas phase biomarkers that emanate from biological samples like urine, breath and faeces may herald a new age of non-invasive diagnostics.
These biomarkers may reflect status in health and disease and can be detected by humans and other animals, to some extent, but far more consistently with instruments.
The continued advancement in micro and nanotechnology has produced a range of compact and sophisticated gas analysis sensors and sensor systems, focussed primarily towards environmental and security applications.
These instruments are now increasingly adapted for use in clinical testing, and with the discovery of new gas volatile compound biomarkers, lead naturally to a new era of non-invasive diagnostics.
|The instruments achieve sensitivities and specificities ranging from 75% to 92% in differentiating disease from controls |
|Alimentary Pharmacology & Therapeutics|
Dr Nwokolo and colleagues from the United Kingdom reviewed current sensor instruments like the electronic nose (e-nose) and ion mobility spectroscopy (IMS), existing technology like gas chromatography-mass spectroscopy (GC-MS), and their application in the detection of gas phase volatile compound biomarkers in medicine – focussing on gastroenterology.
The team performed a systematic search on Medline and Pubmed databases to identify articles relevant to gas and volatile organic compounds.
E-nose and IMS instruments achieve sensitivities and specificities ranging from 75% to 92% in differentiating between inflammatory bowel disease, bile acid diarrhea and colon cancer from controls.
For pulmonary disease, the researchers found that the sensitivities and specificities exceed 90% in differentiating between pulmonary malignancy, pneumonia and obstructive airways disease.
The team noted that these sensitivity levels also hold true for diabetes, and bladder cancer when GC-MS is combined with an e-nose.
Dr Nwokolo's team concluded, "The accurate reproducible sensing of volatile organic compounds using portable near-patient devices is a goal within reach for today's clinicians."