Breath Analysis. An Approach for Smart Diagnostics

Preface
Contents
Physio-Metabolic Monitoring via Breath Employing Real-Time Mass Spectrometry: Importance, Challenges, Potentials, and Pitfalls
	1 Introduction
	2 The Dynamic Nature of Exhaled VOCs
	3 Mass Spectrometric Methods for Real-Time Breath Analysis
	4 Physiological and Metabolic Effects on Breath Biomarkers
	5 Standardization of Real-Time Sampling for Breath Analysis
	6 Applications and Potentials of Physio-Metabolic Monitoring in Breath Analysis
	7 Conclusions and Perspective
	References
Offline Breath Analysis: Standardization of Breath Sampling and Analysis Using Mass Spectrometry and Innovative Algorithms
	1 Introduction
	2 Factors Influencing Offline Breath Analysis
	3 Breath Sampling
		3.1 Exhaled Breath Sampling Portions
		3.2 Breath Containers
		3.3 Standardization of Breath Sampling
	4 Analytical Platforms Based on Mass Spectrometry
		4.1 Offline Analytical Systems
		4.2 Preconcentration Methods
		4.3 Online Analytical Systems
	5 Data Preprocessing
	6 Data Analysis
		6.1 Machine Learning Algorithms
		6.2 Validation of Models
	7 Conclusions and Perspective
	References
Ion Mobility Spectrometry in Clinical and Emergency Setting: Research and Potential Applications
	1 Introduction
	2 Ion Mobility Spectrometry Fundamentals
	3 Sampling Methods
		3.1 Breath Sampling Standardisation
	4 Applications
		4.1 CBRN and Mass Casualty Triage
			4.1.1 Mass Casualty Triage
		4.2 Breath as a Screening Tool for COVID-19
			4.2.1 COVID-19 Studies with GC- IMS
		4.3 Potential Clinical Point of Care Applications for GC-IMS
	5 Future Perspective
	References
Infrared Sensing Strategies: Toward Smart Diagnostics for Exhaled Breath Analysis
	1 Introduction
		1.1 Basic Principles
		1.2 Fundamentals of Infrared Spectroscopic Analysis
		1.3 Infrared Waveguides
		1.4 Infrared Light Sources
		1.5 Infrared Detectors
	2 Measurement Techniques
		2.1 NDIR and FT-IR Spectroscopy Using Thermal Light Sources
		2.2 Direct Laser Absorption Spectroscopy
		2.3 Cavity-Enhanced Laser Absorption Spectroscopy
		2.4 Frequency Comb Spectroscopy
	3 Selected Applications of IR Sensing Technologies in Exhaled Breath Diagnostics
		3.1 Acetone as Biomarker for Diabetes
		3.2 Ammonia Detection in Exhaled Breath
		3.3 CO & NO: Biomarkers for Inflammatory Diseases
		3.4 12CO2/13CO2 Isotope Ratio Analysis and Its Use in Medical Diagnosis
	4 Summary and Outlook
	References
Scopes and Limits of Photoacoustic Spectroscopy in Modern Breath Analysis
	1 Introduction
	2 Theory
		2.1 Molecular Absorption of Light and Relaxation of Excited States
		2.2 Photoacoustic Spectroscopy
			2.2.1 Heat Production Rate at Thermal Equilibrium
			2.2.2 Acoustic Wave Generation
		2.3 Signal Amplification by Resonant Geometries
	3 Overview of Different Photoacoustic Setups and Techniques
		3.1 Electromagnetic Signal Stimulation
			3.1.1 Light Sources
			3.1.2 Amplitude Modulation
			3.1.3 Wavelength Modulation
		3.2 Techniques and Photoacoustic Cell Designs
			3.2.1 Acoustic Resonance Amplification
			3.2.2 Optical Power Amplification
			3.2.3 Fourier Transform and Frequency Comb Photoacoustic Spectroscopy
			3.2.4 Noise and Background Reduction
			3.2.5 Resonance Tracking for Self-calibration
		3.3 Acoustic Signal Transducers
		3.4 Selecting the Most Suitable Setup for Your Requirements
			3.4.1 Limit of Detection and Normalized Noise Equivalent Absorption Coefficient
			3.4.2 Assessment Criteria
	4 Photoacoustic Spectroscopy in Complex Gas Matrices
		4.1 Spectral Cross-Sensitivities
		4.2 Acoustic Attenuation Effects and Resonance Monitoring
		4.3 Molecular Effects in Photoacoustic Spectroscopy
			4.3.1 Heat Capacity Ratio γ in Gaseous Media
			4.3.2 Non-radiative Molecular Relaxation
	5 Selected Applications: Photoacoustic Spectroscopy in Breath Analysis
		5.1 The Human Volatilome Regarding Breath Analysis
		5.2 Breathborne Biomarkers and Photoacoustic Spectroscopy
	6 Summary and Outlook
	References
Advances of Semiconductor Gas Sensing Materials, Structures, and Algorithms for Breath Analysis
	1 Introduction
	2 Sensor Arrays
		2.1 Data Analytics of Sensor Arrays
		2.2 Types of Gas Sensors
	3 Metal Oxide Semiconductor Gas Sensors
		3.1 Sensor Hardware Components
		3.2 Sensing Mechanism of the Sensing Layer
		3.3 Sensor Quality Characteristics
		3.4 Sensor Hardware Optimizations
			3.4.1 Sensing Layer Materials
			3.4.2 Reduction of Grain Size
			3.4.3 Effects of Morphology
			3.4.4 Polymers
			3.4.5 Doping and Light Activation
		3.5 Combining Sensor Hardware Optimizations: Core-Shell Nanostructure and MOFs
		3.6 Sensor Fabrication Process
		3.7 MOS Sensors in Breath Analysis
	4 The Sensor´s Output and Role of Resonance
	5 Advances in Carbon Nanomaterials and Application of Parametric Resonance
	6 Conclusion
	References
Breath Analysis as Part of Pulmonary Function Diagnostics
	1 Introduction
	2 Modern Lung Function Diagnostic
		2.1 Spirometry
		2.2 Body Plethysmography
		2.3 Occlusion Pressure
		2.4 Forced Oscillation Technique
		2.5 Ergo Spirometry/CPET
	3 Diffusion Measurement Techniques
		3.1 Single-Breath Diffusion Measurement and CO Transfer Factor
		3.2 Nitrogen Washout
	4 Blood Gas Analysis
		4.1 Parameters of Blood Gas Analysis
		4.2 Invasive Determination of Blood Gases
		4.3 Non-invasive Determination of Blood Gases
			4.3.1 Transcutaneous Blood Gas Monitoring
			4.3.2 Pulse Oximetry
	5 Expiratory Carbon Dioxide
		5.1 Capnometry
		5.2 Capnovolumetry
	6 Fraction Exhaled Nitric Oxide
		6.1 FeNO Measuring Technology
		6.2 FeNO Measurement in Asthma
		6.3 FeNO Measurement in Other Diseases
		6.4 FeNO Summary
	7 Summary and Outlook
	References