Silica nanoparticles are less toxic to human lung cells when deposited at the air–liquid interface compared to conventional submerged exposure

摘要: Background: Investigations on adverse biological effects of nanoparticles (NPs) in the lung by vitro studies are usually performed under submerged conditions where NPs suspended cell culture media. However, behaviour such as agglomeration and sedimentation complex suspensions is difficult to control hence deposited cellular dose often remains unknown. Moreover, responses might differ from those observed at physiological settings air–liquid interface. Results: In order avoid problems because an altered medium mimic a more realistic situation relevant for inhalation, human A549 epithelial cells were exposed aerosols interphase (ALI) using ALI deposition apparatus (ALIDA). The application electrostatic field allowed particle efficiencies that higher factor than 20 compared unmodified VITROCELL system. We studied two different amorphous silica (particles produced flame synthesis particles suspension Stober method). Aerosols with well-defined sizes concentrations generated commercial electrospray generator or atomizer. Only method generation aerosol containing monodisperse NPs. mass surface was too low induce responses. Therefore, we atomizer which supplied agglomerates thus three orders magnitude doses induced significant effects. estimated independently validated measurements either transmission electron microscopy or, case labelled NPs, fluorescence analyses. Surprisingly, less sensitive evidenced reduced cytotoxicity inflammatory responses. Conclusion: Amorphous qualitatively similar ALI. exposure triggers stronger much lower doses. Hence, warranted decipher whether general vulnerable specific show activities dependent method.