Advances in Mid-Infrared Spectroscopy-Based Sensing Techniques for Exhaled Breath Diagnostics

Abstract

Human exhaled breath consists of more than 3000 volatile organic compounds, many of which are relevant biomarkers for various diseases. Although gas chromatography has been the gold standard for volatile organic compound (VOC) detection in exhaled breath, recent developments in mid-infrared (MIR) laser spectroscopy have led to the promise of compact point-of-care (POC) optical instruments enabling even single breath diagnostics. In this review, we discuss the evolution of MIR sensing technologies with a special focus on photoacoustic spectroscopy, and its application in exhaled breath biomarker detection. While mid-infrared point-of-care instrumentation promises high sensitivity and inherent molecular selectivity, the lack of standardization of the various techniques has to be overcome for translating these techniques into more widespread real-time clinical use.

Artificial Breath Classification Using XGBoost Algorithm for Diabetes Detection

“…Exhaled air contains more carbon dioxide and less oxygen than inhaled air because oxygen is used to generate energy during respiration, while carbon dioxide is produced as a by-product of the energy production process. Among the major components, exhaled breath consists of over 3500 Volatile Organic Compounds (VOCs) and a single breath consists of around 500 various VOCs, which are typically in the part per million (ppm), part per billion (ppb) or part per trillion (ppt) range [ 2 ]. Some of them are named biomarkers since their presence, as well as various concentration levels, may indicate several diseases.…”

Surface Functionalization Utilizing Mesoporous Silica Nanoparticles for Enhanced Evanescent-Field Mid-Infrared Waveguide Gas Sensing

“…Mid-infrared (MIR) spectroscopy can achieve high selectivity waveguide (WG)-based devices for gas sensing by measuring absorption at the characteristic vibrational frequencies of different analytes [1,2]. This ability is advantageous for MIR on-chip small form factor optical sensors when compared to other gas sensing techniques, such as high selectivity but larger form factor in gas chromatography mass spectroscopy (GC-MS) systems [3,4] or a smaller form factor but lower selectivity in metal-oxide semiconductor (MOS) [5][6][7] and electrochemical sensors [8].…”

Экспериментальная установка на базе перестраиваемого в диапазоне волн 5.3-12.8 μm квантово-каскадного лазера для спектрального анализа выдыхаемого человеком воздуха

“…В настоящее время известно, что выдыхаемый воздух состоит более чем из 3000 различных соединений [8]. В состав выдыхаемого человеком воздуха входят летучие органические соединения (ЛОС) и неорганические соединения, такие как водяной пар, аммиак и многие другие вещества.…”

“…В настоящее время целый ряд научных коллективов из нескольких стран проводят исследования для установления взаимосвязей между составом выдыхаемого воздуха и состоянием здоровья человека, а также разрабатывают методы экспресс-диагностики [8,9].…”