Influence of Nanotopography on Phospholipid Bilayer Formation on Silicon Dioxide

Abstract

We have investigated the effect of well-defined nanoscale topography on the 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) lipid vesicle adsorption and supported phospholipid bilayer (SPB) formation on SiO2 surfaces using a quartz crystal microbalance with dissipation monitoring (QCM-D) and atomic force microscopy (AFM). Unilamellar lipid vesicles with two different sizes, 30 and 100 nm, were adsorbed on pitted surfaces with two different pit diameters, 110 and 190 nm, as produced by colloidal lithography, and the behavior was compared to results obtained on flat surfaces. In all cases, complete bilayer formation was observed after a critical coverage of adsorbed vesicles had been reached. However, the kinetics of the vesicle-to-bilayer transformation, including the critical coverage, was significantly altered by surface topography for both vesicle sizes. Surface topography hampered the overall bilayer formation kinetics for the smaller vesicles, but promoted SPB formation for the larger vesicles. Depending on vesicle size, we propose two modifications of the precursor-mediated vesicle-to-bilayer transformation mechanism used to describe supported lipid bilayer formation on the corresponding flat surface. Our results may have important implications for various lipid-membrane-based applications using rough or topographically structured surfaces.

Simultaneous Nanoplasmonic and Quartz Crystal Microbalance Sensing: Analysis of Biomolecular Conformational Changes and Quantification of the Bound Molecular Mass

“…Finally, ∆f 3 /3 saturated at approximately -24 Hz at complete SLB formation with a total increase in D 3 of less than 1 × 10 -6 . These values are consistent with those expected from SLB formation on both unstructured and nanostructured silica-coated QCM crystals, 13 the successful formation of a SLB formation. This is also in agreement with our previous report, in which fluorescence imaging and fluorescence recovery after photobleaching 38 were used to confirm the formation of a continuous and laterally mobile SLB on the same type of support.…”

“…10 Recently, we and others have demonstrated successful SLB formation from vesicles also on nanostructured surfaces, of high relevance for the design of new miniaturized biosensors for studies of cell membrane related biorecognition reactions. [11][12][13] The SLB formation process from vesicle adsorption on planar surfaces have been extensively studied using various fluorescence-* Corresponding authors.…”

Lipid-nanostructure hybrids and their applications in nanobiotechnology

“…The size of the small unilamellar vesicles also has a profound effect on the kinetics of the vesicle-to-bilayer transformation on nanostructures pitted with nanoholes. 19 Studies aimed at understanding the SLB formation on nanotopographic surfaces and designing localized surface plasmon resonance (LSPR)-based membrane biosensors consisting of lipid-covered metal nanoparticles or nanoholes have also been reported. 20,21 Lipid bilayers on nanopatterns Lipid bilayers are selectively assembled as fluids on the surface of specific materials, typically silica.…”

Phospholipid/cholesterol/decanethiol mixtures for direct assembly of immunosensing interfaces

“…It is biocompatible, prevents denaturation of the transducing protein through contact with the metal surface, and may inhibit nonspecific binding [1][2][3][4][5][6][7][8]. The formation of planar lipid-based biomimetic platforms on gold surfaces has aroused the interest of many researchers [9][10][11][12]. One of the most limiting features of this type of assemblies has been the stability of the supported lipid bilayer (SLB) on gold which has led to complex approaches that require especially synthesized molecules, namely polyethylene glycol (PEG)-derivatives [13,14], thiolipids [6,15], biotinylated lipids [14][15][16][17] or other tether layers [18,19].…”