TY - GEN A1 - Machatschek, Rainhard Gabriel A1 - Schöne, Anne-Christin A1 - Raschdorf, Elisa A1 - Ihlenburg, Ramona A1 - Schulz, Burkhard A1 - Lendlein, Andreas T1 - Interfacial properties of morpholine-2,5-dione-based oligodepsipeptides and multiblock copolymers T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Oligodepsipeptides (ODPs) with alternating amide and ester bonds prepared by ring-opening polymerization of morpholine-2,5-dione derivatives are promising matrices for drug delivery systems and building blocks for multifunctional biomaterials. Here, we elucidate the behavior of three telechelic ODPs and one multiblock copolymer containing ODP blocks at the air-water interface. Surprisingly, whereas the oligomers and multiblock copolymers crystallize in bulk, no crystallization is observed at the air-water interface. Furthermore, polarization modulation infrared reflection absorption spectroscopy is used to elucidate hydrogen bonding and secondary structures in ODP monolayers. The results will direct the development of the next ODP-based biomaterial generation with tailored properties for highly sophisticated applications. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1106 KW - block-copolymer KW - enzymatic degradation KW - poly(ester amide)s KW - controlled-release KW - films KW - nanocarriers Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-469755 SN - 1866-8372 IS - 1106 SP - 170 EP - 180 ER - TY - JOUR A1 - Schöne, Anne-Christin A1 - Roch, Toralf A1 - Schulz, Burkhard A1 - Lendlein, Andreas T1 - Evaluating polymeric biomaterial-environment interfaces by Langmuir monolayer techniques JF - Interface : journal of the Royal Society N2 - Polymeric biomaterials are of specific relevance in medical and pharmaceutical applications due to their wide range of tailorable properties and functionalities. The knowledge about interactions of biomaterials with their biological environment is of crucial importance for developing highly sophisticated medical devices. To achieve optimal in vivo performance, a description at the molecular level is required to gain better understanding about the surface of synthetic materials for tailoring their properties. This is still challenging and requires the comprehensive characterization of morphological structures, polymer chain arrangements and degradation behaviour. The review discusses selected aspects for evaluating polymeric biomaterial-environment interfaces by Langmuir monolayer methods as powerful techniques for studying interfacial properties, such as morphological and degradation processes. The combination of spectroscopic, microscopic and scattering methods with the Langmuir techniques adapted to polymers can substantially improve the understanding of their in vivo behaviour. KW - Langmuir monolayer KW - biodegradable polymers KW - air - water interface KW - protein Langmuir layers Y1 - 2017 U6 - https://doi.org/10.1098/rsif.2016.1028 SN - 1742-5689 SN - 1742-5662 VL - 14 PB - Royal Society CY - London ER - TY - JOUR A1 - Schöne, Anne-Christin A1 - Kratz, Karl A1 - Schulz, Burkhard A1 - Lendlein, Andreas T1 - Polymer architecture versus chemical structure as adjusting tools for the enzymatic degradation of oligo(epsilon-caprolactone) based films at the air-water interface JF - Polymer Degradation and Stability N2 - The enzymatic degradation of oligo(epsilon-caprolactone) (OCL) based films at the air-water interface is investigated by Langmuir monolayer degradation (LMD) experiments to elucidate the influence of the molecular architecture and of the chemical structure on the chain scission process. For that purpose, the interactions of 2D monolayers of two star-shaped poly(epsilon-caprolactone)s (PCLs) and three linear OCL based copolyesterurethanes (P(OCL-U)) with the lipase from Pseudomonas cepacia are evaluated in comparison to linear OCL. While the architecture of star-shaped PCL Langmuir layers slightly influences their degradability compared to OCL films, significantly retarded degradations are observed for P(OCL-U) films containing urethane junction units derived from 2, 2 (4), 4-trimethyl hexamethylene diisocyanate (TMDI), hexamethylene diisocyanate (HDI) or lysine ethyl ester diisocyanate (LDI). The enzymatic degradation of the OCL based 2D structures is related to the presence of hydrophilic groups within the macromolecules rather than to the packing density of the film or to the molecular weight. The results reveal that the LMD technique allows the parallel analysis of both the film/enzyme interactions and the degradation process on the molecular level. (C) 2016 Elsevier Ltd. All rights reserved. KW - Langmuir technique KW - Oligo(epsilon-caprolactone) KW - Enzymatic degradation KW - Polymer architecture Y1 - 2016 U6 - https://doi.org/10.1016/j.polymdegradstab.2016.07.010 SN - 0141-3910 SN - 1873-2321 VL - 131 SP - 114 EP - 121 PB - Elsevier CY - Oxford ER - TY - JOUR A1 - Schöne, Anne-Christin A1 - Kratz, Karl A1 - Schulz, Burkhard A1 - Lendlein, Andreas T1 - The relevance of hydrophobic segments in multiblock copolyesterurethanes for their enzymatic degradation at the air-water interface JF - Polymer : the international journal for the science and technology of polymers N2 - The interplay of an enzyme with a multiblock copolymer PDLCL containing two segments of different hydrophilicity and degradability is explored in thin films at the air-water interface. The enzymatic degradation was studied in homogenous Langmuir monolayers, which are formed when containing more than 40 wt% oligo(epsilon-caprolactone) (OCL). Enzymatic degradation rates were significantly reduced with increasing content of hydrophobic oligo(omega-pentadecalactone) (OPDL). The apparent deceleration of the enzymatic process is caused by smaller portion of water-soluble degradation fragments formed from degradable OCL fragments. Beside the film degradation, a second competing process occurs after adding lipase from Pseudomonas cepacia into the subphase, namely the enrichment of the lipase molecules in the polymeric monolayer. The incorporation of the lipase into the Langmuir film is experimentally revealed by concurrent surface area enlargement and by Brewster angle microscopy (BAM). Aside from the ability to provide information about the degradation behavior of polymers, the Langmuir monolayer degradation (LMD) approach enables to investigate polymer-enzyme interactions for non-degradable polymers. (C) 2016 Elsevier Ltd. All rights reserved. KW - Multiblock copolymer KW - Enzymatic polymer degradation KW - Oligo(omega-pentadecalactone) KW - Oligo(epsilon-caprolactone) KW - Langmuir monolayer degradation technique Y1 - 2016 U6 - https://doi.org/10.1016/j.polymer.2016.09.001 SN - 0032-3861 SN - 1873-2291 VL - 102 SP - 92 EP - 98 PB - Elsevier CY - Oxford ER - TY - JOUR A1 - Schöne, Anne-Christin A1 - Schulz, Burkhard A1 - Lendlein, Andreas T1 - Stimuli Responsive and Multifunctional Polymers: Progress in Materials and Applications JF - Macromolecular rapid communications Y1 - 2016 U6 - https://doi.org/10.1002/marc.201600650 SN - 1022-1336 SN - 1521-3927 VL - 37 SP - 1856 EP - 1859 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Schöne, Anne-Christin A1 - Richau, Klaus A1 - Kratz, Karl A1 - Schulz, Burkhard A1 - Lendlein, Andreas T1 - Influence of Diurethane Linkers on the Langmuir Layer Behavior of Oligo[(rac-lactide)-co-glycolide]-based Polyesterurethanes JF - Macromolecular rapid communications N2 - Three oligo[(rac-lactide)-co-glycolide] based polyesterurethanes (OLGA-PUs) containing different diurethane linkers are investigated by the Langmuir monolayer technique and compared to poly[(rac-lactide)-co-glycolide] (PLGA) to elucidate the influence of the diurethane junction units on hydrophilicity and packing motifs of these polymers at the air-water interface. The presence of diurethane linkers does not manifest itself in the Langmuir layer behavior both in compression and expansion experiments when monomolecular films of OLGA-PUs are spread on the water surface. However, the linker retard the evolution of morphological structures at intermediate compression level under isobaric conditions (with a surface pressure greater than 11 mN m(-1)) compared to the PLGA, independent on the chemical structure of the diurethane moiety. The layer thicknesses of both OLGA-PU and PLGA films decrease in the high compression state with decreasing surface pressure, as deduced from ellipsometric data. All films must be described with the effective medium approximation as water swollen layers. KW - Brewster angle microscopy KW - Langmuir monolayer KW - poly[(rac-lactide)-co-glycolide] KW - polyesterurethanes KW - spectroscopic ellipsometry Y1 - 2015 U6 - https://doi.org/10.1002/marc.201500316 SN - 1022-1336 SN - 1521-3927 VL - 36 IS - 21 SP - 1910 EP - 1915 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Schöne, Anne-Christin A1 - Schulz, Burkhard A1 - Richau, Klaus A1 - Kratz, Karl A1 - Lendlein, Andreas T1 - Characterization of Langmuir films prepared from copolyesterurethanes based on oligo(omega-pentadecalactone) and oligo(epsilon-caprolactone)segments JF - Macromolecular chemistry and physics N2 - A series of multiblock copolymers (PDLCL) synthesized from oligo(omega-pentadecalactone) diol (OPDL) and oligo(epsilon-caprolactone) diol (OCL), which are linked by 2,2(4), 4-trimethyl-hexamethylene diisocyanate (TMDI), is investigated by the Langmuir monolayer technique at the air-water interface. Brewster angle microscopy (BAM) and spectroscopic ellipsometry are employed to characterize the polymer film morphologies in situ. PDLCL containing >= 40 wt% OCL segments form homogeneous Langmuir monofilms after spreading. The film elasticity modulus decreases with increasing amounts of OPDL segments in the copolymer. In contrast, the OCL-free polyesterurethane OPDL-TMDI cannot be spread to monomolecular films on the water surface properly, and movable slabs are observed by BAM even at low surface pressures. The results of the in situ morphological characterization clearly show that essential information concerning the reliability of Langmuir monolayer degradation (LMD) experiments cannot be obtained from the evaluation of the pi-A isotherms only. Consequently, in situ morphological characterization turns out to be indispensable for characterization of Langmuir layers before LMD experiments. KW - brewster angle microscopy KW - ellipsometry KW - Langmuir layers KW - morphology KW - polyesterurethanes Y1 - 2014 U6 - https://doi.org/10.1002/macp.201400377 SN - 1022-1352 SN - 1521-3935 VL - 215 IS - 24 SP - 2437 EP - 2445 PB - Wiley-VCH CY - Weinheim ER -