title: Serum protein identification and  quantification of the corona of 5, 15  and 80 nm gold nanoparticles.
abstract: When nanoparticles (NP) enter the body they come into contact with body fluids containing proteins which can adsorb to their surface. These proteins may influence the NP interactions with the biological vicinity, eventually determining their biological fate inside the body. Adsorption of the most abundantly binding proteins was studied after an in vitro 24 hr incubation of monodisperse, negatively charged 5, 15 and 80 nm gold spheres (AuNP) in mouse serum by a two-step analysis: proteomic protein identification and quantitative protein biochemistry. The adsorbed proteins were separated from non-adsorbed proteins by centrifugation and gel electrophoresis and identified using a MALDI-TOF-MS-Proteomics-Analyzer. Quantitative analysis of proteins in gel bands by protein densitometry, required the focus on predominantly binding serum proteins. Numerous proteins adsorbed to the AuNP depending on their size, e.g., apolipoproteins or complement C3. The qualitative and quantitative amount of adsorbed proteins differed between 5, 15 and 80 nm AuNP. Band intensities of adsorbed proteins decreased with increasing AuNP sizes based not only on their mass but also on their surface area. Summarizing, the AuNP surface is covered with serum proteins containing transport and immune related proteins among others. Hence, protein binding depends on the size, surface area and curvature of the AuNP.
authors.affiliation: Comprehensive Pneumology Center, Institute of Lung Biology and Disease and Focus Network Nanoparticles and Health, Helmholtz Zentrum M¨unchen—German Research Center for EnvironmentalHealth, D-85764 Neuherberg/Munich, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Schäffler
authors.forename: Manuela
authors.initials: M
authors.lastname: Semmler-Behnke
authors.forename: Hakan
authors.initials: H
authors.lastname: Sarioglu
authors.forename: Shinji
authors.initials: S
authors.lastname: Takenaka
authors.forename: Alexander
authors.initials: A
authors.lastname: Wenk
authors.forename: Carsten
authors.initials: C
authors.lastname: Schleh
authors.forename: Stefanie M
authors.initials: SM
authors.lastname: Hauck
authors.forename: Blair D
authors.initials: BD
authors.lastname: Johnston
authors.forename: Wolfgang G
authors.initials: WG
authors.lastname: Kreyling
mesh_terms: D000818:Animals; D001798:Blood Proteins / Q000032:analysis* / Q000737:chemistry; D006046:Gold / Q000737:chemistry*; D057446:Hydrodynamics; D013058:Mass Spectrometry; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D051379:Mice; D008807:Mice, Inbred BALB C; D008970:Molecular Weight; D010316:Particle Size; D011485:Protein Binding; D055672:Static Electricity
chemical_list: D001798:Blood Proteins; D006046:Gold