title: Interactions between DPPC as a component of lung surfactant and amorphous silica nanoparticles investigated by HILIC-ESI-MS.
abstract: This paper reports a rapid HILIC-ESI-MS assay to quantify dipalmitoylphosphatidylcholine (DPPC) as component of lung surfactant for nanosafety studies. The technique was used to investigate the concentration-dependent sorption of DPPC to two-sizes of amorphous SiO2 nanoparticles (SiO2-NPs) in a MeOH:H2O (50/50v/v) mixture and in cell culture medium. In MeOH:H2O (50/50v/v), the sorption of DPPC was positively correlated with the nanoparticles concentration. A substantial affinity of small amorphous SiO2-NPs (25nm) to DPPC standard solution compared to bigger SiO2-NPs (75nm) was not confirmed for biological specimens. After dispersion of SiO2-NPs in DPPC containing cell culture medium, the capacity of the SiO2-NPs to bind DPPC was reduced in comparison to a mixture of MeOH:H2O (50/50v/v) regardless from the nanoparticles size. Furthermore, HILIC-ESI-MS revealed that A549 cells internalized DPPC during growth in serum containing medium complemented with DPPC. This finding was in a good agreement with the potential of alveolar type II cells to recycle surfactant components. Binding of lipids present in the cell culture medium to amorphous SiO2-NPs was supported by means of HILIC-ESI-MS, TEM and ICP-MS independently.
authors.affiliation: INM-Leibniz Institute for New Materials, Campus D2 2, 66123 Saarbrücken, Germany. Electronic address: yuliya.silina@leibniz-inm.de.
authors.forename: Yuliya E
authors.initials: YE
authors.lastname: Silina
authors.affiliation: INM-Leibniz Institute for New Materials, Campus D2 2, 66123 Saarbrücken, Germany.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Welck
authors.affiliation: INM-Leibniz Institute for New Materials, Campus D2 2, 66123 Saarbrücken, Germany.
authors.forename: Annette
authors.initials: A
authors.lastname: Kraegeloh
authors.affiliation: INM-Leibniz Institute for New Materials, Campus D2 2, 66123 Saarbrücken, Germany.
authors.forename: Marcus
authors.initials: M
authors.lastname: Koch
authors.affiliation: INM-Leibniz Institute for New Materials, Campus D2 2, 66123 Saarbrücken, Germany.
authors.forename: Claudia
authors.initials: C
authors.lastname: Fink-Straube
mesh_terms: D015060:1,2-Dipalmitoylphosphatidylcholine / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D000327:Adsorption; D002460:Cell Line; D003470:Culture Media / Q000737:chemistry / Q000378:metabolism; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D011650:Pulmonary Alveoli / Q000166:cytology* / Q000378:metabolism; D011663:Pulmonary Surfactants / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D012822:Silicon Dioxide / Q000737:chemistry*; D052616:Solid Phase Extraction / Q000379:methods*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods
chemical_list: D003470:Culture Media; D011663:Pulmonary Surfactants; D015060:1,2-Dipalmitoylphosphatidylcholine; D012822:Silicon Dioxide
keywords: A549 cells; Amorphous SiO(2)-NPs; DPPC; HILIC-ESI–MS; ICP-MS; Phosphor; Solid phase extraction; TEM