Advanced Photonic Sensors Based on Interband Cascade Lasers for Real-Time Mouse Breath Analysis

Abstract

A multiparameter gas sensor based on distributed feedback interband cascade lasers emitting at 4.35 μm and ultrafast electro-spun luminescence oxygen sensors has been developed for the quantification and continuous monitoring of CO/CO isotopic ratio changes and oxygen in exhaled mouse breath samples. Mid-infrared absorption spectra for quantitatively monitoring the enrichment of CO levels were recorded in a miniaturized dual-channel substrate-integrated hollow waveguide using balanced ratiometric detection, whereas luminescence quenching was used for synchronously detecting exhaled oxygen levels. Allan variance analysis verified a CO measurement precision of 1.6‰ during a 480 s integration time. Routine online monitoring of exhaled mouse breath was performed in 14 mechanically ventilated and instrumented mice and demonstrated the feasibility of online isotope-selective exhaled breath analysis within microliters of probed gas samples using the reported combined sensor platform.

Hybrid Analytical Platform Based on Field-Asymmetric Ion Mobility Spectrometry, Infrared Sensing, and Luminescence-Based Oxygen Sensing for Exhaled Breath Analysis

“…Hence, in the future, a data sampling frequency of 180 data points per hour comprising all three orthogonal data sets is anticipated. This is especially remarkable when compared to the data rates currently available via GC-based analysis in our MICU, which provide one data point per hour recorded offline via GC-MS [48].…”

“…The analysis of 12 CO 2 , 13 CO 2 , and O 2 concentrations, as well as the respiratory quotient (RQ) in mouse breath, has already been enabled by our research team via various analytical tools (i.e., iHWG-FTIR spectroscopy, interband cascade laser based tunable diode laser absorption spectroscopy (TDLAS), and LS) [46,47,48]. Besides these already quantifiable analytes in mouse breath, the detection of additional volatile compounds such as acetone and H 2 S is desirable for therapy monitoring and to aid in understanding the underlying metabolism of traumatized mice.…”

Contactless Measurements of Carrier Concentrations in InGaAs Layers for Utilizing in InP-Based Quantum Cascade Lasers by Employing Optical Spectroscopy

“…The latter itself covers a vast area, ranging from medical diagnosis, e.g., detecting cancer markers [ 2 ] by breath analysis, localizing toxic or explosive leaks at factories and waste disposal sites, in-situ industrial process control, up to remotely checking alcohol content in exhaled air inside vehicles [ 3 , 4 ]. Absorption spectra with strong characteristic lines for different gases in that range make it possible to unambiguously identify gas mixture composition, and the state-of-the-art optical sensing systems are able to detect them at ppb concentrations in sub-second temporal resolution using quantum cascade lasers (QCLs) [ 5 , 6 , 7 , 8 ] or interband cascade lasers (ICLs) [ 9 , 10 ]. Many properties of those lasers are determined by properly chosen carrier concentration in respective areas thereof.…”

Hybrid Analytical Platform Based on Field-Asymmetric Ion Mobility Spectrometry, Infrared Sensing, and Luminescence-Based Oxygen Sensing for Exhaled Breath Analysis

“…While Miekisch et al analyzed human breath, our research team has focused on exhaled mouse breath analysis within a mouse intensive care unit (MICU) at the Institute of Anesthesiologic Pathophysiology and Method Development (IAPMD) at Ulm University Medical Center, which requires as an additional challenge the analysis of exceedingly (i.e. few hundreds of microliters) small breath sample volumes [24][25][26]. In order to gain metabolic insights, 12 CO2, 13 CO2 and O2 concentrations as well as the respiratory quotient (RQ) were evaluated using various analytical tools (iHWG-FTIR spectroscopy, interband cascade laser based tunable diode laser absorption spectroscopy (TDLAS) and LS), which were all adapted to the challengingly small breath volumes exhaled by a mouse or any comparable small animal model.…”