Albumin binding and insertion into PS-b-PEO monolayers at air–water interface

Abstract

Interaction of human serum albumin with poly(styrene)-b-poly(ethylene oxide) (PS-b-PEO) monolayer at air/solution interface was studied by measuring surface pressure. The density of PEO chains in the monolayer was controlled using Langmuir trough barriers. The thickness of PS-b-PEO monolayer prior to and after albumin adsorption was computed from in situ surface plasmon resonance (SPR) measurements. Depending on the initial PEO surface density the surface pressure kinetics of albumin insertion displayed two different regimes: below the PEO "pancake-brush" transition albumin binding was initially very rapid and itself induced the "pancake-brush" transition in the monolayer, and above the "pancake-brush" transition where some albumin penetration into the free PS-b-PEO monolayer still occurred into the PEO "brush". In the case of SPR-immobilized monolayer, more than 0.1 PEO chain/nm 2 was required to inhibit albumin or ferritin adsorption. A half-reduction of albumin adsorption required approx. threefold higher PEO surface density than the half-reduction of ferritin adsorption.

Understanding nanodomain morphology formation in dip-coated PS-b-PEO thin films

“…This chemical contrast offers the selective binding of a broader range of additives to one of the blocks to control the size of the nanodomains as well as the desired physicochemical properties. [43][44][45][46][47][48][49][50][51][52] Most of the works involving the combination of dip-coating and PS-b-PEO focus on the fabrication of mesoporous films so far, in which a self-assembled PS-b-PEO structure was used as the template for preparing silica 50,52 or metal oxide mesopores. 51 In all of these works, the effect of dip-coating speed on the final formed mesopores was not discussed, or limited to only one dip-coating regime.…”

Excess fibrinogen adsorption to monolayers of mixed lipids

“…Laboratory studies using lipid monolayers at the A/W interface of a Langmuir trough can be performed under well-defined experimental conditions that allow for the control over the interfacial microstructure [15]. The advent of analytical surface sensitive techniques such as surface plasmon resonance (SPR) and quartz crystal microbalance (QCM) has motivated us to combine these techniques with the Langmuir trough and thus measure molecular events occurring at the monolayer-solution interface in and ex situ [16, 17]. For example, we have used in situ SPR to monitor the efficacy of packing in poly(ethyleneoxide) containing monolayers to suppress protein binding [16].…”

“…The advent of analytical surface sensitive techniques such as surface plasmon resonance (SPR) and quartz crystal microbalance (QCM) has motivated us to combine these techniques with the Langmuir trough and thus measure molecular events occurring at the monolayer-solution interface in and ex situ [16, 17]. For example, we have used in situ SPR to monitor the efficacy of packing in poly(ethyleneoxide) containing monolayers to suppress protein binding [16]. We have also used ex situ QCM to measure protein binding to lipid monolayer mixtures at the A/W interface [17] and assess the potential of protein-monolayer interactions for imprinting the interaction images of protein molecules into the mixed lipids monolayers [18].…”

Protein interaction with a Pluronic-modified poly(lactic acid) Langmuir monolayer

“…Considering the size of a BSA molecule (4 × 4 × 14 nm) [41], the calculated distance between the PEO chains presents a high enough density to ensure that no gaps or spaces on the PLA surface are left uncovered and also provides hindrance to penetration. The value of PEO chain density obtained for reduced protein interaction of the Pluronic-modified PLA film is somewhat smaller, but close to the PEO surface density 0.1 PEO chain/nm 2 found for the PS-PEO block copolymer layer with "brush" conformation presenting effective inhibition of albumin or ferritin adsorption [42]. The range of reduced BSA penetration also involves the beginning of brush formation (system d).…”