@article{WoehlBruhnBadarBertzetal.2012,
  author    = {W{\"o}hl-Bruhn, Stefanie and Badar, Muhammad and Bertz, Andreas and Tiersch, Brigitte and Koetz, Joachim and Menzel, Henning and M{\"u}ller, Peter P. and Bunjes, Heike},
  title     = {Comparison of in vitro and in vivo protein release from hydrogel systems},
  series = {Journal of controlled release},
  volume    = {162},
  journal   = {Journal of controlled release},
  number    = {1},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0168-3659},
  doi       = {10.1016/j.jconrel.2012.05.049},
  pages     = {127 -- 133},
  year      = {2012},
  abstract  = {Hydrogel systems based on hydroxyethyl starch-polyethylene glycol methacrylate (HES-P(EG)(6)MA) or hydroxyethyl starch methacrylate (HES-MA) were used to assess the protein release behavior. Here, we analyzed the in vitro release of FITC-anti-human antibodies incorporated in either HES-P(EG)(6)MA or HES-MA hydrogel delivery systems in PBS or human serum. In addition, hydrogel disks and microparticles prepared from the two polymers were subcutaneously implanted in BALB/c mice. The in vivo release of FITC-IgG was non-invasively monitored by an in vivo imaging system (IVIS 200) over a time period of up to 3 months. The imaging system allowed to asses individual animals over time, therefore only a small number of animals was required to obtain high quality data. The reduction in fluorescence intensity at the site of administration was compared to in vitro release profiles. These investigations demonstrated a sustained release from HES-MA hydrogel disks compared to rapidly degrading HES-P(EG)(6)MA disks and microparticles. The sustained release from HES-MA disks could be further optimized by using increased polymer concentrations. Human serum as in vitro release medium reflected better the in vivo release from HES-P(EG)(6)MA systems than PBS, suggesting that the presence of organic substances like proteins or lipids may play a significant role for the release kinetics.},
  language  = {en}
}
@article{MenzelRuetherStumpeetal.1998,
  author    = {Menzel, Henning and R{\"u}ther, M. and Stumpe, Joachim and Fischer, Thomas M.},
  title     = {Discrimination of structural order and chromophore aggregation as factors effecting the photo-reorientation of azobenzene in co-polyglutamate LB-films},
  year      = {1998},
  language  = {en}
}
@article{MenzelRuetherStumpeetal.1998,
  author    = {Menzel, Henning and R{\"u}ther, M. and Stumpe, Joachim and Fischer, Thomas M.},
  title     = {Discrimination of structural order and chromophore aggregation as factors effecting the photo-reorientation of Azobenzene in copolyglutamate LB-films.},
  year      = {1998},
  language  = {en}
}
@article{BertzWoehlBruhnMietheetal.2013,
  author    = {Bertz, Andreas and W{\"o}hl-Bruhn, Stefanie and Miethe, Sebastian and Tiersch, Brigitte and Koetz, Joachim and Hust, Michael and Bunjes, Heike and Menzel, Henning},
  title     = {Encapsulation of proteins in hydrogel carrier systems for controlled drug delivery influence of network structure and drug size on release rate},
  series = {Journal of biotechnology},
  volume    = {163},
  journal   = {Journal of biotechnology},
  number    = {2},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0168-1656},
  doi       = {10.1016/j.jbiotec.2012.06.036},
  pages     = {243 -- 249},
  year      = {2013},
  abstract  = {Novel hydrogels based on hydroxyethyl starch modified with polyethylene glycol methacrylate (HES-P(EG)(6)MA) were developed as delivery system for the controlled release of proteins. Since the drug release behavior is supposed to be related to the pore structure of the hydrogel network the pore sizes were determined by cryo-SEM, which is a mild technique for imaging on a nanometer scale. The results showed a decreasing pore size and an increase in pore homogeneity with increasing polymer concentration. Furthermore, the mesh sizes of the hydrogels were calculated based on swelling data. Pore and mesh size were significantly different which indicates that both structures are present in the hydrogel. The resulting structural model was correlated with release data for bulk hydrogel cylinders loaded with FITC-dextran and hydrogel microspheres loaded with FITC-IgG and FITC-dextran of different molecular size. The initial release depended much on the relation between hydrodynamic diameter and pore size while the long term release of the incorporated substances was predominantly controlled by degradation of the network of the much smaller meshes.},
  language  = {en}
}
@article{BourgatTierschKoetzetal.2020,
  author    = {Bourgat, Yannick and Tiersch, Brigitte and Koetz, Joachim and Menzel, Henning},
  title     = {Enzyme degradable polymersomes from chitosan-g-[poly-l-lysine-block-epsilon-caprolactone] copolymer},
  series = {Macromolecular bioscience},
  volume    = {21},
  journal   = {Macromolecular bioscience},
  number    = {1},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1616-5187},
  doi       = {10.1002/mabi.202000259},
  pages     = {1 -- 9},
  year      = {2020},
  abstract  = {The scope of this study includes the synthesis of chitosan-g-[peptide-poly-epsilon-caprolactone] and its self-assembly into polymeric vesicles employing the solvent shift method. In this way, well-defined core-shell structures suitable for encapsulation of drugs are generated. The hydrophobic polycaprolactone side-chain and the hydrophilic chitosan backbone are linked via an enzyme-cleavable peptide. The synthetic route involves the functionalization of chitosan with maleimide groups and the preparation of polycaprolactone with alkyne end-groups. A peptide functionalized with a thiol group on one side and an azide group on the other side is prepared. Thiol-ene click-chemistry and azide-alkyne Huisgen cycloaddition are then used to link the chitosan and poly-epsilon-caprolactone chains, respectively, with this peptide. For a preliminary study, poly-l-lysin is a readily available and cleavable peptide that is introduced to investigate the feasibility of the system. The size and shape of the polymersomes are studied by dynamic light scattering and cryo-scanning electron microscopy. Furthermore, degradability is studied by incubating the polymersomes with two enzymes, trypsin and chitosanase. A dispersion of polymersomes is used to coat titanium plates and to further test the stability against enzymatic degradation.},
  language  = {en}
}
@misc{BourgatTierschKoetzetal.2020,
  author    = {Bourgat, Yannick and Tiersch, Brigitte and Koetz, Joachim and Menzel, Henning},
  title     = {Enzyme degradable polymersomes from chitosan-g-[poly-l-lysine-block-epsilon-caprolactone] copolymer},
  series = {Zweitver{\"o}ffentlichungen der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  journal   = {Zweitver{\"o}ffentlichungen der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  number    = {1},
  issn      = {1866-8372},
  doi       = {10.25932/publishup-56658},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-566584},
  pages     = {11},
  year      = {2020},
  abstract  = {The scope of this study includes the synthesis of chitosan-g-[peptide-poly-epsilon-caprolactone] and its self-assembly into polymeric vesicles employing the solvent shift method. In this way, well-defined core-shell structures suitable for encapsulation of drugs are generated. The hydrophobic polycaprolactone side-chain and the hydrophilic chitosan backbone are linked via an enzyme-cleavable peptide. The synthetic route involves the functionalization of chitosan with maleimide groups and the preparation of polycaprolactone with alkyne end-groups. A peptide functionalized with a thiol group on one side and an azide group on the other side is prepared. Thiol-ene click-chemistry and azide-alkyne Huisgen cycloaddition are then used to link the chitosan and poly-epsilon-caprolactone chains, respectively, with this peptide. For a preliminary study, poly-l-lysin is a readily available and cleavable peptide that is introduced to investigate the feasibility of the system. The size and shape of the polymersomes are studied by dynamic light scattering and cryo-scanning electron microscopy. Furthermore, degradability is studied by incubating the polymersomes with two enzymes, trypsin and chitosanase. A dispersion of polymersomes is used to coat titanium plates and to further test the stability against enzymatic degradation.},
  language  = {en}
}
@article{BorgerKuliskovskaHubmannetal.2005,
  author    = {Borger, V. and Kuliskovska, O. and Hubmann, K. G. and Stumpe, Joachim and Huber, M. and Menzel, Henning},
  title     = {Novel polymers to study the influence of the azobenzene content on the photo-induced surface relief grating formation},
  issn      = {1022-1352},
  year      = {2005},
  abstract  = {The influence of the azobenzene concentration on the photo-induced surface relief grating (SRG) formation in polymer films was investigated. Two series of polymers with 4-alkoxy-4'-cyanoazobenzene side groups were synthesized. In series A, the degree of substitution was varied, while in series B, azobenzene and biphenyl groups were introduced in varying composition, but the concentration of non-reacted HEMA-groups was kept constant. Photo-induction of the dichroism and the SRG was studied as function of the azobenzene concentration. An optimum was found for the SRG formation (76\%), while the highest dichroism was induced at the lowest azobenzene concentration of 20\%. The restriction of rotational and translational molecular motions observed at higher azobenzene concentration was explained by pi-pi stacking of the azobenzene moieties and interaction of unreacted HEMA groups},
  language  = {en}
}
@article{ZieglerFischerMenzeletal.1998,
  author    = {Ziegler, A. and Fischer, Thomas M. and Menzel, Henning and Stumpe, Joachim},
  title     = {Photo-Induced modification and photo-orientation in LB-multilayers of thermotropic polymers containing azobenzene side groups},
  year      = {1998},
  language  = {en}
}
@article{StumpeGeueFischeretal.1995,
  author    = {Stumpe, Joachim and Geue, Thomas and Fischer, Thomas M. and Menzel, Henning},
  title     = {Photochemically induced changes of structures in LB-multilayers of amphotropic polymers},
  year      = {1995},
  language  = {en}
}
@article{NavarroShkilnyyTierschetal.2009,
  author    = {Navarro, Salvador and Shkilnyy, Andriy and Tiersch, Brigitte and Taubert, Andreas and Menzel, Henning},
  title     = {Preparation, characterization, and thermal gelation of amphiphilic alkyl-poly(ethyleneimine)},
  issn      = {0743-7463},
  doi       = {10.1021/La9013569},
  year      = {2009},
  abstract  = {Amphiphilic alkyl-poly(ethyleneimine)s (alkyl-PEI) with different degrees of polymerization have been produced by alkaline hydrolysis of alkyl-poly(2-methyl-2-oxazoline). Potentiometric titration of the alkyl-PEI shows the influence of the alkyl chain and the degree of polymerization on the titration curves and hence on the polymer conformation. Karl Fischer titration has been used to determine the water content in the polymers. Subsequent X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and differential scanning calorimetry (DSC) measurements prove the existence of different hydration states of the PEI even under dry storage conditions. Upon cooling from hot aqueous Solutions, hydrogels form. The gelation concentration decreases with increasing degree of polymerization of the PEI segment. Scanning electron microscopy (SEM and cryo-SEM) of the hydrogels reveal an alkyl-PEI fibrous network composed of fan-like units. DSC shows that the percentages of bound and free water in the hydrogels depend on the concentration of polar amino groups.},
  language  = {en}
}