Surface Properties of Pulmonary Surfactant Sampled by Bronchoalveolar Lavage and by Electrostatic Exhaled Aerosol Trapping

Abstract

Abstract The development of efficient methods for non-invasive collection of alveolar lining fluid (ALF) samples containing pulmonary surfactant (PS) components and the study of the surface activity of the obtained native material is relevant for the diagnosis of inflammatory pneumopathies of the lungs. The paper presents an electrostatic aerosol trapping (ESAT) mobile complex for capturing droplets of ALF contained in an exhaled air. Passing the exhaled air through the corona discharge area results in the aerosol droplets charging and their further transferring by electrostatic force into a water surface, where they accumulate forming an adsorbed layer. Additionally, ALF samples were collected using a bronchoalveolar lavage (BAL). The surface properties of the PS obtained by both methods have been examined using the capillary wave method, which was previously modified by the authors specifically for biomedical applications. Significant difference was found in the results obtained with ESAT and BAL in the group of healthy subjects, which can be explained by different origin of the samples obtained by these techniques. Furthermore, significant difference in surface properties was established in the samples collected from healthy volunteers and patient with disseminated tuberculosis, while we did not find significant differences in the limited inflammatory process. The results presented in the paper demonstrate high potential of the proposed non-invasive technique for clinical usage.