@article{NeffevonRuestenLangeBrauneetal.2013, author = {Neffe, Axel T. and von R{\"u}sten-Lange, Maik and Braune, Steffen and L{\"u}tzow, Karola and Roch, Toralf and Richau, Klaus and Jung, Friedrich and Lendlein, Andreas}, title = {Poly(ethylene glycol) grafting to Poly(ether imide) membranes - influence on protein adsorption and Thrombocyte adhesion}, series = {Macromolecular bioscience}, volume = {13}, journal = {Macromolecular bioscience}, number = {12}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1616-5187}, doi = {10.1002/mabi.201300309}, pages = {1720 -- 1729}, year = {2013}, abstract = {The chain length and end groups of linear PEG grafted on smooth surfaces is known to influence protein adsorption and thrombocyte adhesion. Here, it is explored whether established structure function relationships can be transferred to application relevant, rough surfaces. Functionalization of poly(ether imide) (PEI) membranes by grafting with monoamino PEG of different chain lengths (M-n=1kDa or 10kDa) and end groups (methoxy or hydroxyl) is proven by spectroscopy, changes of surface hydrophilicity, and surface shielding effects. The surface functionalization does lead to reduction of adsorption of BSA, but not of fibrinogen. The thrombocyte adhesion is increased compared to untreated PEI surfaces. Conclusively, rough instead of smooth polymer or gold surfaces should be investigated as relevant models.}, language = {en} } @article{FedericoPiercePilusoetal.2015, author = {Federico, Stefania and Pierce, Benjamin F. and Piluso, Susanna and Wischke, Christian and Lendlein, Andreas and Neffe, Axel T.}, title = {Design of Decorin-Based Peptides That Bind to CollagenI and their Potential as Adhesion Moieties in Biomaterials}, series = {Angewandte Chemie : a journal of the Gesellschaft Deutscher Chemiker ; International edition}, volume = {54}, journal = {Angewandte Chemie : a journal of the Gesellschaft Deutscher Chemiker ; International edition}, number = {37}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1433-7851}, doi = {10.1002/anie.201505227}, pages = {10980 -- 10984}, year = {2015}, abstract = {Mimicking the binding epitopes of protein-protein interactions by using small peptides is important for generating modular biomimetic systems. A strategy is described for the design of such bioactive peptides without accessible structural data for the targeted interaction, and the effect of incorporating such adhesion peptides in complex biomaterial systems is demonstrated. The highly repetitive structure of decorin was analyzed to identify peptides that are representative of the inner and outer surface, and it was shown that only peptides based on the inner surface of decorin bind to collagen. The peptide with the highest binding affinity for collagenI, LHERHLNNN, served to slow down the diffusion of a conjugated dye in a collagen gel, while its dimer could physically crosslink collagen, thereby enhancing the elastic modulus of the gel by one order of magnitude. These results show the potential of the identified peptides for the design of biomaterials for applications in regenerative medicine.}, language = {en} } @article{VukicevicNeffeLuetzowetal.2015, author = {Vukicevic, Radovan and Neffe, Axel T. and Luetzow, Karola and Pierce, Benjamin F. and Lendlein, Andreas}, title = {Conditional Ultrasound Sensitivity of Poly[(N-isopropylacrylamide)-co-(vinyl imidazole)] Microgels for Controlled Lipase Release}, series = {Macromolecular rapid communications}, volume = {36}, journal = {Macromolecular rapid communications}, number = {21}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1022-1336}, doi = {10.1002/marc.201500311}, pages = {1891 -- 1896}, year = {2015}, abstract = {Triggering the release of cargo from a polymer network by ultrasonication as an external, non-invasive stimulus can be an interesting concept for on-demand release. Here, it is shown that, in pH-and thermosensitive microgels, the ultrasound sensitivity of the polymer network depends on the external conditions. Crosslinked poly[(N-isopropylacrylamide)-co-(vinyl imidazole)] microgels showed a volume phase transition temperature (VPTT) of 25-50 degrees C, which increases with decreasing pH. Above the VPTT the polymer chains are collapsed, while below VPTT they are extended. Only in the case of maximum observed swelling, where the polymer chains are expanded, the microgels are mechanically fragmented through ultrasonication. In contrast, when the polymer chains are partially collapsed it is not possible to manipulate the microgels by ultrasound. Additionally, the ultrasound-induced on-demand release of wheat germ lipase from the microgels could be demonstrated successfully. The principle of conditional ultrasound sensitivity is likely to be general and can be used for selection of matrix-cargo combinations.}, language = {en} }