Sensorgrams of mAb 12G5 binding (100 nM) to CXCR4-ACMs immobilized at low RU (ca. 1400) via biotin/spteptavidin immobilization of the embedding polymersome matrix.

<p>The analyte was injected in triplicate, at cycle 7, 14, and 21. Intermediate cycles involved blank injections. The blue line shows the fit to the curve assuming 1∶1 binding kinetics. The inset shows the relative decrease in binding activity of the surface as measured by the binding level 4 s before the end of the injection.</p

Kinetic parameters extracted from fitting the binding curves of concentration series of three different mAbs against a single preparation of immobilized CXCR4 ACMs.

[a]<p>KD for 12G5 binding to CXCR4-ACMS shown in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0110847#pone-0110847-g002" target="_blank">Figure 2</a> was 60.2±17 nM.</p><p>Kinetic parameters extracted from fitting the binding curves of concentration series of three different mAbs against a single preparation of immobilized CXCR4 ACMs.</p

Kinetic screening of 12G5 mAb binding to CXCR4-ACMs immobilized onto biosensor chips.

<p>A: Ab was injected at increasing concentrations (6.25–400 nM) over 100 s, followed by a buffer wash (without regeneration) between injections (immobilization level: ca. 5000 RU; biotin/streptavidin immobilization). B. Saturation binding of 125-I SDF1α to CXCR4-ACMs. A dissociation constant of 8.4 nM was determined. C. The same series of measurements as shown in Fig. 2 A, conducted using immobilized VLPS (immobilization level: 5000 RU).</p

Mixing, Diffusion, and Percolation in Binary Supported Membranes Containing Mixtures of Lipids and Amphiphilic Block Copolymers

Substrate-mediated fusion of small polymersomes, derived from mixtures of lipids and amphiphilic block copolymers, produces hybrid, supported planar bilayers at hydrophilic surfaces, monolayers at hydrophobic surfaces, and binary monolayer/bilayer patterns at amphiphilic surfaces, directly responding to local measures of (and variations in) surface free energy. Despite the large thickness mismatch in their hydrophobic cores, the hybrid membranes do not exhibit microscopic phase separation, reflecting irreversible adsorption and limited lateral reorganization of the polymer component. With increasing fluid-phase lipid fraction, these hybrid, supported membranes undergo a fluidity transition, producing a fully percolating fluid lipid phase beyond a critical area fraction, which matches the percolation threshold for the immobile point obstacles. This then suggests that polymer-lipid hybrid membranes might be useful models for studying obstructed diffusion, such as occurs in lipid membranes containing proteins

Mixing, Diffusion, and Percolation in Binary Supported Membranes Containing Mixtures of Lipids and Amphiphilic Block Copolymers

Substrate-mediated fusion of small polymersomes, derived from mixtures of lipids and amphiphilic block copolymers, produces hybrid, supported planar bilayers at hydrophilic surfaces, monolayers at hydrophobic surfaces, and binary monolayer/bilayer patterns at amphiphilic surfaces, directly responding to local measures of (and variations in) surface free energy. Despite the large thickness mismatch in their hydrophobic cores, the hybrid membranes do not exhibit microscopic phase separation, reflecting irreversible adsorption and limited lateral reorganization of the polymer component. With increasing fluid-phase lipid fraction, these hybrid, supported membranes undergo a fluidity transition, producing a fully percolating fluid lipid phase beyond a critical area fraction, which matches the percolation threshold for the immobile point obstacles. This then suggests that polymer-lipid hybrid membranes might be useful models for studying obstructed diffusion, such as occurs in lipid membranes containing proteins