Detection of Volatile Organic Compounds with Secondary Electrospray Ionization and Proton Transfer Reaction High-Resolution Mass Spectrometry: A Feature Comparison.

The analysis of volatiles is of high relevance for a wide range of applications from environmental air sampling and security screening to potential medical applications. High-resolution mass spectrometry methods offer a particularly wide compound coverage, sensitivity, and selectivity. Online approaches allow direct analysis in real time without the need for sample preparation.

On-Line Analysis of Exhaled Breath .

On-line analysis of exhaled breath offers insight into a person's metabolism without the need for sample preparation or sample collection. Due to its noninvasive nature and the possibility to sample continuously, the analysis of breath has great clinical potential. The unique features of this technology make it an attractive candidate for applications in medicine, beyond the task of diagnosis.

Real-Time Breath Analysis Reveals Specific Metabolic Signatures of COPD Exacerbations.

Background: Exacerbations of COPD are defined by acute worsening of respiratory symptoms leading to a change in therapy. Identifying altered metabolic processes in patients at risk for future exacerbations is desirable for treatment optimization, the development of new therapeutic strategies, and perhaps diagnostic value. We aimed to identify affected pathways using the profiles of volatile organic compounds in exhaled breath from patients with COPD with and without frequent exacerbations (≥ 2 exacerbations within the past 12 months).

Molecular breath analysis supports altered amino acid metabolism in idiopathic pulmonary fibrosis.

Background And Objective: Diagnosis of idiopathic pulmonary fibrosis (IPF) is complex and its pathogenesis is poorly understood. Recent findings indicate elevated levels of proline and other amino acids in lung tissue of IPF patients which may also be of diagnostic value. Following these findings, we hypothesized that such altered metabolic profiles would be mirrored in exhaled breath and could therefore be captured non-invasively in real time.

Real-Time Monitoring of Tricarboxylic Acid Metabolites in Exhaled Breath.

The tricarboxylic acid (TCA) cycle is one of the most important metabolic pathway for cellular respiration in aerobic organisms. It provides and collects intermediates for many other interconnecting pathways and acts as a hub connecting metabolism of carbohydrates, fatty acids, and amino acids. Alteration in intracellular levels of its intermediates has been linked with a wide range of illnesses ranging from cancer to cellular necrosis or liver cirrhosis.

On-line Breath Metabolomics in Respiratory Diseases using Secondary Electrospray Ionization-Mass Spectrometry.

Every second we are exhaling hundreds of endogenous and exogenous compounds that originate from blood and lung tissue. Obtaining metabolic information via exhaled breath analysis has been an emerging topic since the 1970s. Secondary electrospray ionization-mass spectrometry is a relatively new technique to detect these metabolites on-line in a highly sensitive and specific fashion.

Real-time exhaled breath analysis in patients with cystic fibrosis and controls.

We aimed at defining profiles of volatile organic compounds in exhaled breath from patients with cystic fibrosis (CF) using a novel real-time mass spectrometry technique. In this prospective matched case-control study, 30 patients with CF, and 30 healthy control subjects were matched one-to-one according to age, gender, and smoking state. We performed exhaled breath analysis by untargeted secondary electrospray ionization-high resolution mass spectrometry (SESI-HRMS).

Real-time mass spectrometric identification of metabolites characteristic of chronic obstructive pulmonary disease in exhaled breath.

Background: New mass spectrometry (MS) techniques analysing exhaled breath have the potential to better define airway diseases. Here, we present our work to profile the volatile organic compounds (VOCs) in exhaled breath from patients with chronic obstructive pulmonary disease (COPD), using real-time MS, and relate this disease-specific breath profile to functional disease markers.

Methods: In a matched cohort study, patients with COPD, according to GOLD criteria, were recruited.

Translating secondary electrospray ionization-high-resolution mass spectrometry to the clinical environment.

While there has been progress in making use of breath tests to guide clinical decision making, the full potential of exhaled breath analysis still remains to be exploited. Here we summarize some of the reasons why this is the case, what we have done so far to overcome some of the existing obstacles, and our vision of how we think breath analysis will play a more prominent role in the coming years. In particular, we envision that real-time high-resolution mass spectrometry will provide valuable information in biomarker discovery studies.

Metabolic effects of inhaled salbutamol determined by exhaled breath analysis.

We explore whether real-time breath analysis by high resolution mass spectrometry is suitable to monitor changes at the metabolic level due to inhaling bronchodilator medication. We compared the breath levels of metabolites in a group of patients (n = 50) at baseline and 10 and 30 min after inhalation of 200 μg salbutamol. The same procedure was performed with a group of controls (n = 48) inhaling a placebo spray.

Mass-Spectrometric Detection of Omega-Oxidation Products of Aliphatic Fatty Acids in Exhaled Breath.

Omega-oxidation is a fatty acid degradation pathway that can occur alternatively to the dominant β-oxidation. The dysregulation of fatty acid oxidation has been related with a variety of diseases, termed fatty acid oxidation disorders. This work shows evidence for real-time detection in exhaled breath of the complete series of saturated linear ω-hydroxyalkanoic acids, ω-oxoalkanoic acids, and alkanedioic acids with carbon chain lengths of 5-15.

Expanding metabolite coverage of real-time breath analysis by coupling a universal secondary electrospray ionization source and high resolution mass spectrometry--a pilot study on tobacco smokers.

Online breath analysis is an attractive approach to track exhaled compounds without sample preparation. Current commercially available real-time breath analysis platforms require the purchase of a full mass spectrometer. Here we present an ion source compatible with virtually any preexisting atmospheric pressure ionization mass spectrometer that allows real-time analysis of breath.

Effects of CPAP therapy withdrawal on exhaled breath pattern in obstructive sleep apnoea.

Background: Obstructive sleep apnoea (OSA) is highly prevalent and associated with cardiovascular and metabolic changes. OSA is usually diagnosed by polysomnography which is time-consuming and provides little information on the patient's phenotype thus limiting a personalised treatment approach. Exhaled breath contains information on metabolism which can be analysed by mass spectrometry within minutes.