Research & Development

PExA’s strategy for research is to co-operate with leading international research groups and carry on the work performed over the past few years in identifying biomarkers for various lung diseases.

In parallel with this work, PExA is running a development project to further develop, streamline and simplify the PExA method to collect particles from the small airways.

Publications involving PExAs method

Broberg E, Mechanically ventilated patients exhibit decreased particle flow in exhaled breath as compared to normal breathing patients, ERJ Open Resarch, 2020
Kokelj S, Intra-individual variation of particles in exhaled air and of the contents of Surfactant protein A and albumin, PLOS ONE, 2020
Stenlo M, Increased particle flow rate from airways precedes clinical signs of ARDS in a porcine model of LPS-induced acute lung injury, American Journal of Physiology, 2020
Broberg E, Particle Flow Profiles From the Airways Measured by PExA Differ in Lung Transplant Recipients Who Develop Primary Graft Dysfunction, Experimental and Clinical Transplanlantion, 2019
Carpaij O, Assessing small airways dysfunction in asthma, asthma remission and healthy controls using particles in exhaled air, ERJ Open Research, 2019
Behndig A L, Surfactant Protein A in particles in exhaled air (PExA), bronchial lavage and bronchial wash - a methodological comparison Respiratory Research, 2019
Broberg E, Different particle flow patterns from the airways after recruitment manoeuvres using volume-controlled or pressure-controlled ventilation Intensive Care Medicine Experimental, 2019
Bake B, et al. Exhaled particles and small airways Respiratory Research, 2019
Soares M, et al. Particles in exhaled air (PExA): non-invasive phenotyping of small airways disease in adult asthma Journal of Breath research, 2018
Broberg E, et al. A new way of monitoring mechanical ventilation by measurement of particle flow from the Airways using Pexa method in vivo and during ex vivo lung perfusion in DCD lung transplantation Intensive Care Medicine Experimental, 2018
Ljungkvist G, et al. Two techniques to sample non-volatiles in breath—exemplified by methadone Journal of Breath Research, 2017
Larsson P, et al. The effect of exhalation flow on endogenous particle emission and phospholipid composition. Respiratory Physiology & Neurobiology, 2017
Ildiko Horváth, Peter J. Barnes, et al. A European Respiratory Society technical standard: exhaled biomarkers in lung disease. European Respiratory Journal, 2017
Bake B, Exhaled Particles After a Standardized Breathing Maneuver. J Aerosol Med Pulm Drug Deliv. 2017
Ericson P, Low levels of exhaled surfactant protein A associated with BOS after lung transplantation. Transplantation Direct 2016
Emilsson ÖI, Respiratory symptoms, sleep-disordered breathing and biomarkers in nocturnal gastroesophageal reflux. Respir Res. 2016.
Beck O, Potential of Mass Spectrometry in Developing Clinical Laboratory Biomarkers of Nonvolatiles in Exhaled Breath. Clin Chem. 2016;62(1):84-91.
Larsson P, Exhaled particles as markers of small airway inflammation in subjects with asthma. Clin Physiol Funct Imaging, 2015
Lärstad M, Surfactant protein A in exhaled endogenous particles is decreased in chronic obstructive pulmonary disease (COPD) patients: a pilot study. PLoS One 2015 Dec
Bredberg A, Analysis of manganese and iron in exhaled endogenous particles. J Analyt Antomic Spect 2014:29:730 -735
Olin AC. Particles in Exhaled Air—A novel method of sampling of-non-volatiles in exhaled air. In Volatile Biomarkers. Editor Amann A.
Emilsson OI, Biomarkers for gastroesophageal reflux in respiratory diseases. Gastroenterol Res Pract. 2013;2013:148086.
Bredberg A, Comparison of exhaled endogenous particles from smokers and non-smokers using multivariate analysis. Respiration. 2013;86(2):135-42.
Holmgren H, Effects of breath holding at low and high lung volumes on amount of exhaled particles. Respir Physiol Neurobiol. 2013;185:228-34.
Olin AC. Induced sputum, exhaled nitric oxide, and particles in exhaled air in assessing airways inflammation in occupational exposures. Clin Chest Med. 2012;33:771-82.
Bredberg A, Exhaled endogenous particles contain lung proteins. Clin Chem 2012; 58:431-40.
Almstrand AC, TOF-SIMS analysis of exhaled particles from patients with asthma and healthy controls. Eur Respir J 2012;39:59-66.
Larsson L, Surfactant protein A and albumin in particles in exhaled air. Respir Med 2012; 106:197-204
Holmgren H, Relation between humidity and size of exhaled particles. Aerosol Med Pulm Drug Deliv 2011;24:254-60
Holmgren H, Size distribution of exhaled particles in the range from 0.01 to 2.0 μm. Journal ofAerosol Science 2010;41:439-446
Almstrand AC, Effect of Airway Opening on Production of Exhaled Particles. J Appl Physiol 2010;108:584-8
Almstrand AC, Airway monitoring by collection and mass spectrometric analysis of exhaled particles. Anal Chem. 2009; 81:662-8.

PExA 2.0

PExA 2.0 has been developed on the basis of the instrument developed at the Sahlgrenska Academy in nine specimens (PExA 1.0) and...



Suitable standard methods that can be used for analysis include ELISA, MS, LC and HPLC. As a service to those customers who...



For each sampling, disposable items are required such as substrate surfaces and nozzles. These components...