Breath Analysis for Medical Diagnosis

Abstract

The purpose of this review is to highlight the advances in technology and understanding in the field of breath analysis for medical diagnosis. A critical review of the methods of breath collection, treatment, and analysis is given, highlighting the problems facing the field and areas where promising advancement has been made. One particular area of interest is centered around electronic noses, ideally, portable devices which aim to mimic biological olifactory systems in analysing gases to produce odor fingerprints. Furthermore, recent work has shown it is possible to modify the basic sensor materials to both improve their performance, increase their tolerance to factors such as water vapour interferance which often leave the sensor system de-sensitized to the gaseous biomarkers, and enhance their selectivity. It will be shown how it is possible to accurately quantify concentrations of VOC's INTERNATIONAL JOURNAL ON SMART SENSING AND INTELLIGENT SYSTEMS, VOL. 5, NO. 2, JUNE 2012 401 and make disease diagnosis from analysis of the collected data which compare favorably with traditional medical diagnostic techniques.

Breath sensors for lung cancer diagnosis

“…Structures with high crystallinity such as nanowires exhibit greater stability and can overcome problems like irreversibility (Hill and Binions, 2012). Irreversibility is commonly associated with elevated working temperatures and observed therefore in case of metal oxide sensors.…”

“…Based on their earlier studies (Binions et al, 2009a), Hill and Binions stated that incorporation of zeolites onto the surface of a porous metal-oxide sensor (MOS) improves the selectivity and sensitivity (Hill and Binions, 2012). Enhanced response and discriminating power were achieved with a solid state MOS sensor composed of the hydrogen variants of zeolites as transformation element, overlaid on top of the porous chromium titanium oxide sensing element (Binions et al, 2009b).…”

Breath Acetone-Based Non-Invasive Detection of Blood Glucose Levels

“…The breath acetone concentration ranging from 1.7 ppm to 3.7 ppm can be detected in diabetic patients [19,20], whereas it varies between 0.3 and 0.9 ppm for healthy humans [21]. Over 1000 VOC's have been detected to date in the ppmv (parts per million by volume) to pptv (parts per trillion by volume) concentrations [22]. Optical fiber made of nanostructured films has been used for the detection of VOCs [23].…”

Wearable Bio and Chemical Sensors

“…These techniques require complex and expensive equipment not conducive to wearable formats. Chemical sensor arrays or electronic noses (e-noses) are an alternative cheaper, portable, and faster approach that have shown promising results in the fields of renal disease, lung cancer, and diabetes [13]. With these methods breath analysis still has challenges regarding standardization of methods of collection, treatment, and conditioning of samples.…”