Kocun, Marta

[["dc.bibliographiccitation.firstpage","2508"],["dc.bibliographiccitation.issue","11"],["dc.bibliographiccitation.journal","Soft Matter"],["dc.bibliographiccitation.lastpage","2516"],["dc.bibliographiccitation.volume","6"],["dc.contributor.author","Kocun, Marta"],["dc.contributor.author","Mueller, Waltraut"],["dc.contributor.author","Maskos, Michael"],["dc.contributor.author","Mey, Ingo"],["dc.contributor.author","Geil, Burkhard"],["dc.contributor.author","Steinem, Claudia"],["dc.contributor.author","Janshoff, Andreas"],["dc.date.accessioned","2017-09-07T11:46:43Z"],["dc.date.available","2017-09-07T11:46:43Z"],["dc.date.issued","2010"],["dc.description.abstract","We show how the viscoelastic properties of membranes formed from poly(butadiene)-block-poly(ethylene oxide) (PB(130)-b-PEO(66)) block copolymers can be locally accessed by atomic force microscopy. Polymer membranes are spread on microstructured porous silicon substrates from PB(130)-b-PEO(66) vesicles by decreasing the osmotic pressure of the solution. Local viscoelastic properties of the pore-spanning polymer membranes were obtained from site-specific indentation experiments. Elastic moduli of these membranes were in the order of few MPa, while the elastic moduli of crosslinked membranes considerably increased to few GPa. Furthermore, the energy dissipation and velocity dependence of the hysteresis between indentation and relaxation were quantified and compared with a modified Kelvin-Voigt model. Relaxation times were in the order of hundreds of milliseconds explaining why the stiffness of the membrane increases with increasing indentation velocity."],["dc.identifier.doi","10.1039/b924650a"],["dc.identifier.gro","3143006"],["dc.identifier.isi","000278046300021"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/473"],["dc.language.iso","en"],["dc.notes.intern","WoS Import 2017-03-10"],["dc.notes.status","final"],["dc.notes.submitter","PUB_WoS_Import"],["dc.relation.issn","1744-683X"],["dc.title","Viscoelasticity of pore-spanning polymer membranes derived from giant polymersomes"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","6935"],["dc.bibliographiccitation.issue","9"],["dc.bibliographiccitation.journal","ACS Nano"],["dc.bibliographiccitation.lastpage","6944"],["dc.bibliographiccitation.volume","5"],["dc.contributor.author","Lazzara, Thomas D."],["dc.contributor.author","Carnarius, Christian"],["dc.contributor.author","Kocun, Marta"],["dc.contributor.author","Janshoff, Andreas"],["dc.contributor.author","Steinem, Claudia"],["dc.date.accessioned","2017-09-07T11:43:25Z"],["dc.date.available","2017-09-07T11:43:25Z"],["dc.date.issued","2011"],["dc.description.abstract","Anodic aluminum oxide (AAO) is a porous material having aligned cylindrical compartments with 55-60 nm diameter pores, and being several micrometers deep. A protocol was developed to generate pore-spanning fluid lipid bilayers separating the attoliter-sized compartments of the nanoporous material from the bulk solution, while preserving the optical transparency of the AAO. The AAO was selectively functionalized by silane chemistry to spread giant unilamellar vesicles (GUVs) resulting In large continuous membrane patches covering the pores. Formation of fluid single lipid bilayers through GUV rupture could be readily observed by fluorescence microscopy and further supported by conservation of membrane surface area, before and after GUV rupture. Fluorescence recovery after photobleaching gale low immobile fractions (5-15%) and lipid diffusion coefficients similar to those found for bilayers on silica. The entrapment of molecules within the porous underlying cylindrical compartments, as well as the exclusion of macromolecules from the nanopores, demonstrate the barrier fun ton of the pore-spanning membranes and could be investigated in three-dimensions using confocal laser scanning fluorescence imaging."],["dc.identifier.doi","10.1021/nn201266e"],["dc.identifier.gro","3142672"],["dc.identifier.isi","000295187400021"],["dc.identifier.pmid","21797231"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/101"],["dc.language.iso","en"],["dc.notes.intern","WoS Import 2017-03-10"],["dc.notes.status","final"],["dc.notes.submitter","PUB_WoS_Import"],["dc.relation.eissn","1936-086X"],["dc.relation.issn","1936-0851"],["dc.title","Separating Attoliter-Sized Compartments Using Fluid Pore-Spanning Lipid Bilayers"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.journal","Abstracts of Papers of the American Chemical Society"],["dc.bibliographiccitation.volume","242"],["dc.contributor.author","Kocun, Marta"],["dc.contributor.author","Lazzara, Thomas D."],["dc.contributor.author","Steinem, Claudia"],["dc.contributor.author","Janshoff, Andreas"],["dc.date.accessioned","2018-11-07T08:53:05Z"],["dc.date.available","2018-11-07T08:53:05Z"],["dc.date.issued","2011"],["dc.identifier.isi","000299378301606"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/22322"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Amer Chemical Soc"],["dc.publisher.place","Washington"],["dc.relation.eventlocation","Denver, CO"],["dc.relation.issn","0065-7727"],["dc.title","Solvent-free, pore-spanning model membranes studied by fluorescence microscopy and atomic force microscopy"],["dc.type","conference_abstract"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","7672"],["dc.bibliographiccitation.issue","12"],["dc.bibliographiccitation.journal","Langmuir"],["dc.bibliographiccitation.lastpage","7680"],["dc.bibliographiccitation.volume","27"],["dc.contributor.author","Kocun, Marta"],["dc.contributor.author","Lazzara, Thomas D."],["dc.contributor.author","Steinem, Claudia"],["dc.contributor.author","Janshoff, Andreas"],["dc.date.accessioned","2017-09-07T11:44:09Z"],["dc.date.available","2017-09-07T11:44:09Z"],["dc.date.issued","2011"],["dc.description.abstract","Plasma membrane tension, produced by the underlying cytoskeleton, governs many dynamic processes such as fusion, blebbing exo- and endocytosis, cell migration, and adhesion. Here, a new protocol is introduced to model this intricate and often overlooked aspect of the plasma membrane. Lipid bilayers spanning pores of 600 nm radius were prepared by adsorption and spreading of giant unilamellar vesicles (GUVs) on moderately hydrophilic porous substrates prepared by gold-coating and subsequent self-assembly of a mercaptoethanol monolayer. Rupture of GUVs formed tens of micrometer sized pore-spanning membrane patches displaying low tension of sigma <= 3.5 mN m(-1) and lateral diffusion constants of about 8 mu m(2) s(-1). Site-specific force indentation experiments were performed to determine membrane tension as a function of lipid composition: for pure DOPC bilayers, a tension of 1.018 +/- 0.014 mN m(-1) was measured, which was increased by the addition of cholesterol to 3.50 +/- 0.15 mN m(-1). Compared to DOPC, POPC bilayers displayed a larger tension of 2.00 +/- 0.09 mN m(-1). Addition and subsequent partitioning of 2-propanol was shown to significantly reduce the membrane tension as a function of its concentration."],["dc.identifier.doi","10.1021/la2003172"],["dc.identifier.gro","3142713"],["dc.identifier.isi","000291500700046"],["dc.identifier.pmid","21619014"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/148"],["dc.language.iso","en"],["dc.notes.intern","WoS Import 2017-03-10"],["dc.notes.status","final"],["dc.notes.submitter","PUB_WoS_Import"],["dc.relation.issn","0743-7463"],["dc.title","Preparation of Solvent-Free, Pore-Spanning Lipid Bilayers: Modeling the Low Tension of Plasma Membranes"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original"],["dspace.entity.type","Publication"]]