TY  - JOUR
A1  - Hentrich, Doreen
A1  - Taabache, Soraya
A1  - Brezesinski, Gerald
A1  - Lange, Nele
A1  - Unger, Wolfgang
A1  - Kuebel, Christian
A1  - Bertin, Annabelle
A1  - Taubert, Andreas
T1  - A Dendritic Amphiphile for Efficient Control of Biomimetic Calcium Phosphate Mineralization
JF  - Macromolecular bioscience
N2  - 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.
Y1  - 2017
U6  - https://doi.org/10.1002/mabi.201600524
SN  - 1616-5187
SN  - 1616-5195
VL  - 17
SP  - 2541
EP  - 2548
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Hentrich, Doreen
A1  - Brezesinski, Gerald
A1  - Kuebel, Christian
A1  - Bruns, Michael
A1  - Taubert, Andreas
T1  - Cholesteryl Hemisuccinate Monolayers Efficiently Control Calcium Phosphate Nucleation and Growth
JF  - Crystal growth & design : integrating the fields of crystal engineering and crystal growth for the synthesis and applications of new materials
N2  - The article describes the phase behavior of cholesteryl hemisuccinate at the air-liquid interface and its effect on calcium phosphate (CP) mineralization. The amphiphile forms stable monolayers with phase transitions at the air-liquid interface from a gas to a tilted liquid-condensed (TLC) and finally to an untilted liquid-condensed (ULC) phase. CP mineralization beneath these monolayers leads to crumpled CP layers made from individual plates. The main crystal phase is octacalcium phosphate (OCP) along with a minor fraction of hydroxyapatite (HAP), as confirmed by X-ray photoelectron spectroscopy, energy dispersive X-ray spectroscopy, bright field transmission electron microscopy, and electron diffraction.
Y1  - 2017
U6  - https://doi.org/10.1021/acs.cgd.7b00753
SN  - 1528-7483
SN  - 1528-7505
VL  - 17
SP  - 5764
EP  - 5774
PB  - American Chemical Society
CY  - Washington
ER  - 
TY  - JOUR
A1  - Reinicke, Stefan
A1  - Rees, Huw C.
A1  - Espeel, Pieter
A1  - Vanparijs, Nane
A1  - Bisterfeld, Carolin
A1  - Dick, Markus
A1  - Rosencrantz, Ruben R.
A1  - Brezesinski, Gerald
A1  - de Geest, Bruno G.
A1  - Du Prez, Filip E.
A1  - Pietruszka, Jörg
A1  - Böker, Alexander
T1  - Immobilization of 2-Deoxy-D-ribose-5-phosphate Aldolase in Polymeric Thin Films via the Langmuir-Schaefer Technique
JF  - ACS applied materials & interfaces
N2  - 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.
KW  - Langmuir-Schaefer
KW  - enzyme immobilization
KW  - 2-deoxy-D-ribose-5-phosphate aldolase
KW  - polymeric thin film
KW  - poly(N-isopropylacrylamide)
KW  - thiolactone
Y1  - 2017
U6  - https://doi.org/10.1021/acsami.6b13632
SN  - 1944-8244
VL  - 9
SP  - 8317
EP  - 8326
PB  - American Chemical Society
CY  - Washington
ER  -