The formation of an on-specific protein corona around nanoparticles (NPs) has been identified as one of the culprits for failed nanomedicine.T he amount and type of adsorbed protein from the blood plasma are knownt o determine the fate of NPs and the accessibility of targeting ligands.H erein, we show that the adsorbed protein may not only enlarge the NPs and change their surface properties but also,i nt he case of soft NPs such as polymer micelles,l ead to deformation. Poly(1-O-methacryloyl -b-D-fructopyranose)-bpoly(methylmethacrylate) (P(1-O-MAFru)-b-PMMA) block co-polymers were self-assembled into NPs with as pherical core-shell morphology as determined by small angle neutron scattering (SANS). Upon incubation with albumin, TEM, SANS,a nd small angle X-rays cattering (SAXS) revealed the adsorption of albumin and deformation of the NPs with aspheroid geometry.Removal of the protein led to the reversal of the morphology backt ot he spherical core-shell structure. Structural studies and cell studies of uptake of the NPs imply that the observed deformation mayinfluence blood circulation time and cell uptake.

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One can take advantage of the influence of a polymer conjugated with a protein to control the thermal stability and the deployment of the protein. Here, the structural properties are reported of the protein–polymer conjugate myoglobin (Mb)‐poly(ethyl ethylene phosphate) (PEEP) in the native and unfolded conformations, in order to understand the respective roles of the protein and of the polymer size in the stability of the conjugate. The effect is also investigated of the grafting density of the linear biodegradable polyphosphoesters covalently attached to the protein. It is observed that, while the conjugation process at room temperature does not modify the secondary and tertiary structure of the Mb, the unfolding process, as a function of temperature, depends on the grafting density. Small angle neutron scattering reveals that, at room temperature, conjugation does not alter the size of the native protein and that the thickness of the polymer shell around the protein increases as a function of grafting density and of polymer molecular weight. The denatured form of all conjugates is described by an unfolded chain and a correlation length due to the presence of local stiffness.

The supramolecular assembly process is a widespread phenomenon found in both synthetically engineered and naturally occurring systems, such as colloids, liquid crystals, and micelles. However, a basic understanding of the...