@article{TangSmaczniakTepperetal.2022, author = {Tang, Jo Sing Julia and Smaczniak, Aline Debrassi and Tepper, Lucas and Rosencrantz, Sophia and Aleksanyan, Mina and D{\"a}hne, Lars and Rosencrantz, Ruben R.}, title = {Glycopolymer based LbL multilayer thin films with embedded liposomes}, series = {Macromolecular bioscience}, volume = {22}, journal = {Macromolecular bioscience}, number = {4}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1616-5187}, doi = {10.1002/mabi.202100461}, pages = {9}, year = {2022}, abstract = {Layer-by-layer (LbL) self-assembly emerged as an efficient technique for fabricating coating systems for, e.g., drug delivery systems with great versatility and control. In this work, protecting group free and aqueous-based syntheses of bioinspired glycopolymer electrolytes aredescribed. Thin films of the glycopolymers are fabricated by LbL self-assembly and function as scaffolds for liposomes, which potentially can encapsulate active substances. The adsorbed mass, pH stability, and integrity of glycopolymer coatings as well as the embedded liposomes are investigated via whispering gallery mode (WGM) technology and quartz crystal microbalance with dissipation (QCM-D) monitoring , which enable label-free characterization. Glycopolymer thin films, with and without liposomes, are stable in the physiological pH range. QCM-D measurements verify the integrity of lipid vesicles. Thus, the fabrication of glycopolymer-based surface coatings with embedded and intact liposomes is presented.}, language = {en} } @phdthesis{Tang2022, author = {Tang, Jo Sing Julia}, title = {Biofunctional polymers for medical applications}, doi = {10.25932/publishup-56363}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-563639}, school = {Universit{\"a}t Potsdam}, pages = {III, 150, V}, year = {2022}, abstract = {Carbohydrates are found in every living organism, where they are responsible for numerous, essential biological functions and processes. Synthetic polymers with pendant saccharides, called glycopolymers, mimic natural glycoconjugates in their special properties and functions. Employing such biomimetics furthers the understanding and controlling of biological processes. Hence, glycopolymers are valuable and interesting for applications in the medical and biological field. However, the synthesis of carbohydrate-based materials can be very challenging. In this thesis, the synthesis of biofunctional glycopolymers is presented, with the focus on aqueous-based, protecting group free and short synthesis routes to further advance in the field of glycopolymer synthesis. A practical and versatile precursor for glycopolymers are glycosylamines. To maintain biofunctionality of the saccharides after their amination, regioselective functionalization was performed. This frequently performed synthesis was optimized for different sugars. The optimization was facilitated using a design of experiment (DoE) approach to enable a reduced number of necessary experiments and efficient procedure. Here, the utility of using DoE for optimizing the synthesis of glycosylamines is discussed. The glycosylamines were converted to glycomonomers which were then polymerized to yield biofunctional glycopolymers. Here, the glycopolymers were aimed to be applicable as layer-by-layer (LbL) thin film coatings for drug delivery systems. To enable the LbL technique, complimentary glycopolymer electrolytes were synthesized by polymerization of the glycomonomers and subsequent modification or by post-polymerization modification. For drug delivery, liposomes were embedded into the glycopolymer coating as potential cargo carriers. The stability as well as the integrity of the glycopolymer layers and liposomes were investigated at physiological pH range. Different glycopolymers were also synthesized to be applicable as anti-adhesion therapeutics by providing advanced architectures with multivalent presentations of saccharides, which can inhibit the binding of pathogene lectins. Here, the synthesis of glycopolymer hydrogel particles based on biocompatible poly(N-isopropylacrylamide) (NiPAm) was established using the free-radical precipitation polymerization technique. The influence of synthesis parameters on the sugar content in the gels and on the hydrogel morphology is discussed. The accessibility of the saccharides to model lectins and their enhanced, multivalent interaction were investigated. At the end of this work, the synthesis strategies for the glycopolymers are generally discussed as well as their potential application in medicine.}, language = {en} } @article{RosencrantzTangSchulteOsseilietal.2019, author = {Rosencrantz, Sophia and Tang, Jo Sing Julia and Schulte-Osseili, Christine and B{\"o}ker, Alexander and Rosencrantz, Ruben R.}, title = {Glycopolymers by RAFT Polymerization as Functional Surfaces for Galectin-3}, series = {Macromolecular chemistry and physics}, volume = {220}, journal = {Macromolecular chemistry and physics}, number = {20}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1022-1352}, doi = {10.1002/macp.201900293}, pages = {7}, year = {2019}, abstract = {Glycan-protein interactions are essential biological processes with many disease-related modulations and variations. One of the key proteins involved in tumor progression and metastasis is galectin-3 (Gal-3). A lot of effort is put into the development of Gal-3 inhibitors as new therapeutic agents. The avidity of glycan-protein interactions is strongly enhanced by multivalent ligand presentation. Multivalent presentation of glycans can be accomplished by utilizing glycopolymers, which are polymers with pendent glycan groups. For the production of glycopolymers, glycomonomers are synthesized by a regioselective, microwave-assisted approach starting from lactose. The resulting methacrylamide derivatives are polymerized by RAFT and immobilized on gold surfaces using the trithiocarbonate group of the chain transfer agent. Surface plasmon resonance spectroscopy enables the label free kinetic characterization of Gal-3 binding to these multivalent glycopolymers. The measurements indicate oligomerization of Gal-3 upon exposure to multivalent environments and reveal strong specific interaction with the immobilized polymers.}, language = {en} }