@article{ReinickeReesEspeeletal.2017, author = {Reinicke, Stefan and Rees, Huw C. and Espeel, Pieter and Vanparijs, Nane and Bisterfeld, Carolin and Dick, Markus and Rosencrantz, Ruben R. and Brezesinski, Gerald and de Geest, Bruno G. and Du Prez, Filip E. and Pietruszka, J{\"o}rg and B{\"o}ker, Alexander}, title = {Immobilization of 2-Deoxy-D-ribose-5-phosphate Aldolase in Polymeric Thin Films via the Langmuir-Schaefer Technique}, series = {ACS applied materials \& interfaces}, volume = {9}, journal = {ACS applied materials \& interfaces}, publisher = {American Chemical Society}, address = {Washington}, issn = {1944-8244}, doi = {10.1021/acsami.6b13632}, pages = {8317 -- 8326}, year = {2017}, abstract = {A synthetic protocol for the fabrication of ultrathin polymeric films containing the enzyme 2-deoxy-D-ribose-5-phosphate aldolase from Escherichia coli (DERA(EC)) is presented. Ultrathin enzymatically active films are useful for applications in which only small quantities of active material are needed and at the same time quick response and contact times without diffusion limitation are wanted. We show how DERA as an exemplary enzyme can be immobilized in a thin polymer layer at the air-water interface and transferred to a suitable support by the Langmuir-Schaefer technique under full conservation of enzymatic activity. The polymer in use is a poly(N-isopropylacrylamide-co-N-2-thiolactone acrylamide) (P(NIPAAm-co-TlaAm)) statistical copolymer in which the thiolactone units serve a multitude of purposes including hydrophobization of the polymer, covalent binding of the enzyme and the support and finally cross-linking of the polymer matrix. The application of this type of polymer keeps the whole approach simple as additional cocomponents such as cross-linkers are avoided.}, language = {en} } @article{HentrichTaabacheBrezesinskietal.2017, author = {Hentrich, Doreen and Taabache, Soraya and Brezesinski, Gerald and Lange, Nele and Unger, Wolfgang and Kuebel, Christian and Bertin, Annabelle and Taubert, Andreas}, title = {A Dendritic Amphiphile for Efficient Control of Biomimetic Calcium Phosphate Mineralization}, series = {Macromolecular bioscience}, volume = {17}, journal = {Macromolecular bioscience}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1616-5187}, doi = {10.1002/mabi.201600524}, pages = {2541 -- 2548}, year = {2017}, abstract = {The phase behavior of a dendritic amphiphile containing a Newkome-type dendron as the hydrophilic moiety and a cholesterol unit as the hydrophobic segment is investigated at the air-liquid interface. The amphiphile forms stable monomolecular films at the airliquid interface on different subphases. Furthermore, the mineralization of calcium phosphate beneath the monolayer at different calcium and phosphate concentrations versus mineralization time shows that at low calcium and phosphate concentrations needles form, whereas flakes and spheres dominate at higher concentrations. Energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and electron diffraction confirm the formation of calcium phosphate. High-resolution transmission electron microscopy and electron diffraction confirm the predominant formation of octacalcium phosphate and hydroxyapatite. The data also indicate that the final products form via a complex multistep reaction, including an association step, where nano-needles aggregate into larger flake-like objects.}, language = {en} }