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'Host-guest' interactions between self-assembled micellar nanostructures from amphiphilic invertible polymers (AIPs) and two peptides, swine-origin Influenza A surface protein Hemagglutinin and research antibody peptide V5, are investigated by changing the polymer concentration and polymer/peptide ratio in the aqueous solution. Formation of mixed micellar assemblies from AIP and each peptide is revealed using detailed 1H NMR spectroscopic study. Peptide molecule localization in the micellar assemblies depends on the specific interactions between amino acid functional groups of the peptide and polymer fragments. The resulting mixed micellar structures can be considered as a promising material toward delivery and stimuli-responsive sustained release of peptides. [ABSTRACT FROM AUTHOR]

The enzymogel nanoparticle made of a magnetic core and polymer brush shell demonstrates a novel type of remote controlled phase-boundary biocatalysis that involves remotely directed binding to and engulfing insoluble substrates, high mobility, and stability of the catalytic centers. The mobile enzymes reside in the polymer brush scaffold and shuttle between the enzymogel interior and surface of the engulfed substrate in the bioconversion process. Biocatalytic activity of the mobile enzymes is preserved in the enzymogel while the brush-like architecture favors the efficient interfacial interaction when the enzymogel spreads over the substrate and extends substantially the reaction area as compared with rigid particles. [ABSTRACT FROM AUTHOR]

A new synthetic route for two different amphiphilic macromolecular structures containing hydrophilic poly(ethylene glycol) (PEG) and lipophilic cholesterol fragments is described. The novelty of the synthesis is in combining hydrophilic and lipophilic fragments in a backbone using functional groups of the pyromellitic dianhydride (PMDA) molecule. The ability of the new oligomers to undergo self-assembly and solubilization of lipophilic molecules in an aqueous medium is compared. The new oligomers form self-assemblies capable of solubilizing lipophilic 'guest' molecules in an aqueous medium. Their high solubilization capacity and biodegradability, as well as other properties (size distribution, ζ-potential), make the synthesized macromolecules good candidates for biomedical applications. Using the developed approach, amphiphilic macromolecules with regulated surface activity can be synthesized by combining PEG of varying lengths with different hydrophobic fragments (for example, fatty alcohols) in the backbone. [ABSTRACT FROM AUTHOR]

The article discusses a study which synthesized porous polyacrylamide (PAAm) hydrogels with improved mechanical properties and regular pore distribution. It notes that leaching out of chemically modified silica particles was used to form hydrogel pores. Results of the study showed that the dispersibility of the porogen material in the hydrogel composition was improved by the grafted PAAM layer on the silica surface. It cites the steps involved in developing porous hydrogels.

A functionalization of iron oxide nanoparticles (NPs) of different diameters by the amphiphilic invertible polymer, (PEG600‐alt‐PTHF650)k (PEG and PTHF stand for poly(ethylene glycol) and poly(tetrahydrofuran), respectively), leads to different NP/polymer architectures for dye/drug uptake and release, as is reported here for the first time. It is demonstrated that 18.6 ± 1.4 and 11.9 ± 0.6 nm NPs are individually coated by this polymer, while 5.9 ± 0.6 nm NPs form nanoparticle clusters (NPCs) which could be isolated by either ultracentrifugation or magnetic separation. This phenomenon is most likely due to the character of the (PEG600‐alt‐PTHF650)k macromolecule with alternating hydrophilic and hydrophobic fragments and its dimensions sufficient to cause NP clustering. Utilizing Rhodamine B base (RBB) and doxorubicin (DOX), the data on uptake upon mixing and further release via inversion into octanol (mimicking the penetration of the cell biomembrane) are presented. The magnetic NPCs display enhanced uptake and release of both RBB and DOX most likely due to the higher retained polymer amount. The NPCs also display exceptional magnetic resonance imaging properties. This and the high uptake/release efficiency of the NPCs combined with easy magnetic separation make them promising for theranostic probes for magnetically targeted drug delivery. [ABSTRACT FROM AUTHOR]

Ein Enzymogel mit einer neuen Variante der Biokatalyse an der Phasengrenze wird von S. Minko, A. Voronov et al. in der Zuschrift auf S. 493 ff. vorgestellt. Die Enzymogelpartikel vereinen die Enzymkatalyse im Partikel mit der reizausgelösten extrakapsulären Biokatalyse – der biokatalytischen Umwandlung von Substraten, die mit dem Enzymogel in Kontakt stehen, wenn das Enzym das Substrat einhüllt – und der reizausgelösten Wiederaufnahme der freigesetzten Enzyme zur Wiederverwertung (Titelbild: Ella Marushchenko). [ABSTRACT FROM AUTHOR]

An enzymogel that shows a novel type of phase‐boundary biocatalysis is described by S. Minko, A. Voronov, et al. in their Communication on page 483 ff. The enzymogel particles combine biocatalysis involving enzymes in the particle, stimuli‐triggered extracapsular biocatalysis, biocatalytic conversion of substrates contacting the enzymogel when the enzymes engulf the substrate, and stimuli‐triggered reattachment of the released enzymes for their reuse (cover image courtesy of Ella Marushchenko). [ABSTRACT FROM AUTHOR]