@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} } @article{DoeringGrigorievTapioetal.2021, author = {Doering, Ulrike and Grigoriev, Dmitry and Tapio, Kosti and Rosencrantz, Sophia and Rosencrantz, Ruben R. and Bald, Ilko and B{\"o}ker, Alexander}, title = {About the mechanism of ultrasonically induced protein capsule formation}, series = {RSC Advances : an international journal to further the chemical sciences / Royal Society of Chemistry}, volume = {11}, journal = {RSC Advances : an international journal to further the chemical sciences / Royal Society of Chemistry}, number = {27}, publisher = {RSC Publishing}, address = {London}, issn = {2046-2069}, doi = {10.1039/d0ra08100k}, pages = {16152 -- 16157}, year = {2021}, abstract = {In this paper, we propose a consistent mechanism of protein microcapsule formation upon ultrasound treatment. Aqueous suspensions of bovine serum albumin (BSA) microcapsules filled with toluene are prepared by use of high-intensity ultrasound following a reported method. Stabilization of the oil-in-water emulsion by the adsorption of the protein molecules at the interface of the emulsion droplets is accompanied by the creation of the cross-linked capsule shell due to formation of intermolecular disulfide bonds caused by highly reactive species like superoxide radicals generated sonochemically. The evidence for this mechanism, which until now remained elusive and was not proven properly, is presented based on experimental data from SDS-PAGE, Raman spectroscopy and dynamic light scattering.}, language = {en} } @article{PacholskiRosencrantzRosencrantzetal.2020, author = {Pacholski, Claudia and Rosencrantz, Sophia and Rosencrantz, Ruben R. and Balderas-Valadez, Ruth Fabiola}, title = {Plasmonic biosensors fabricated by galvanic displacement reactions for monitoring biomolecular interactions in real time}, series = {Analytical and bioanalytical chemistry : a merger of Fresenius' journal of analytical chemistry, Analusis and Quimica analitica}, volume = {412}, journal = {Analytical and bioanalytical chemistry : a merger of Fresenius' journal of analytical chemistry, Analusis and Quimica analitica}, number = {14}, publisher = {Springer}, address = {Heidelberg}, issn = {1618-2642}, doi = {10.1007/s00216-020-02414-0}, pages = {3433 -- 3445}, year = {2020}, abstract = {Optical sensors are prepared by reduction of gold ions using freshly etched hydride-terminated porous silicon, and their ability to specifically detect binding between protein A/rabbit IgG and asialofetuin/Erythrina cristagalli lectin is studied. The fabrication process is simple, fast, and reproducible, and does not require complicated lab equipment. The resulting nanostructured gold layer on silicon shows an optical response in the visible range based on the excitation of localized surface plasmon resonance. Variations in the refractive index of the surrounding medium result in a color change of the sensor which can be observed by the naked eye. By monitoring the spectral position of the localized surface plasmon resonance using reflectance spectroscopy, a bulk sensitivity of 296 nm +/- 3 nm/RIU is determined. Furthermore, selectivity to target analytes is conferred to the sensor through functionalization of its surface with appropriate capture probes. For this purpose, biomolecules are deposited either by physical adsorption or by covalent coupling. Both strategies are successfully tested, i.e., the optical response of the sensor is dependent on the concentration of respective target analyte in the solution facilitating the determination of equilibrium dissociation constants for protein A/rabbit IgG as well as asialofetuin/Erythrina cristagalli lectin which are in accordance with reported values in literature. These results demonstrate the potential of the developed optical sensor for cost-efficient biosensor applications.}, 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} }