TY - JOUR A1 - Hoang, Hoa T. A1 - Mertens, Monique A1 - Wessig, Pablo A1 - Sellrie, Frank A1 - Schenk, Jörg A. A1 - Kumke, Michael Uwe T1 - Antibody Binding at the Liposome-Water Interface BT - a FRET Investigation toward a Liposome-Based Assay JF - ACS Omega N2 - Different signal amplification strategies to improve the detection sensitivity of immunoassays have been applied which utilize enzymatic reactions, nanomaterials, or liposomes. The latter are very attractive materials for signal amplification because liposomes can be loaded with a large amount of signaling molecules, leading to a high sensitivity. In addition, liposomes can be used as a cell-like "bioscaffold" to directly test recognition schemes aiming at cell-related processes. This study demonstrates an easy and fast approach to link the novel hydrophobic optical probe based on [1,3]dioxolo[4,5-f]-[1,3]benzodioxole (DBD dye mm239) with tunable optical properties to hydrophilic recognition elements (e.g., antibodies) using liposomes for signal amplification and as carrier of the hydrophobic dye. The fluorescence properties of mm239 (e.g., long fluorescence lifetime, large Stokes shift, high photostability, and high quantum yield), its high hydrophobicity for efficient anchoring in liposomes, and a maleimide bioreactive group were applied in a unique combination to build a concept for the coupling of antibodies or other protein markers to liposomes (coupling to membranes can be envisaged). The concept further allowed us to avoid multiple dye labeling of the antibody. Here, anti-TAMRA-antibody (DC7-Ab) was attached to the liposomes. In proof-of-concept, steady-state as well as time-resolved fluorescence measurements (e.g., fluorescence depolarization) in combination with single molecule detection (fluorescence correlation spectroscopy, FCS) were used to analyze the binding interaction between DC7-Ab and liposomes as well as the binding of the antigen rhodamine 6G (R6G) to the antibody. Here, the Forster resonance energy transfer (FRET) between mm239 and R6G was monitored. In addition to ensemble FRET data, single-molecule FRET (PIE-FRET) experiments using pulsed interleaved excitation were used to characterize in detail the binding on a single-molecule level to avoid averaging out effects. KW - energy-transfer KW - immunoassay KW - complexes KW - probes Y1 - 2018 U6 - https://doi.org/10.1021/acsomega.8b03016 SN - 2470-1343 VL - 3 IS - 12 SP - 18109 EP - 18116 PB - American Chemical Society CY - Washington ER - TY - THES A1 - Justynska, Justyna T1 - Towards a library of functional block copolymers : synthesis and colloidal properties T1 - Hin zu einer Bibliothek von funktionalen Blockcopolymeren : Synthese und kolloidale Eigenschaften N2 - Understanding the principles of self-organisation exhibited by block copolymers requires the combination of synthetic and physicochemical knowledge. The ability to synthesise block copolymers with desired architecture facilitates the ability to manipulate their aggregation behaviour, thus providing the key to nanotechnology. Apart from relative block volumes, the size and morphology of the produced nanostructures is controlled by the effective incompatibility between the different blocks. Since polymerisation techniques allowing for the synthesis of well-defined block copolymers are restricted to a limited number of monomers, the ability to tune the incompatibility is very limited. Nevertheless, Polymer Analogue Reactions can offer another possibility for the production of functional block copolymers by chemical modifications of well-defined polymer precursors. Therefore, by applying appropriate modification methods both volume fractions and incompatibility, can be adjusted. Moreover, copolymers with introduced functional units allow utilization of the concept of molecular recognition in the world of synthetic polymers. The present work describes a modular synthetic approach towards functional block copolymers. Radical addition of functional mercaptanes was employed for the introduction of diverse functional groups to polybutadiene-containing block copolymers. Various modifications of 1,2-polybutadiene-poly(ethylene oxide) block copolymer precursors are described in detail. Furthermore, extension of the concept to 1,2-polybutadiene-polystyrene block copolymers is demonstrated. Further investigations involved the self-organisation of the modified block copolymers. Formed aggregates in aqueous solutions of block copolymers with introduced carboxylic acid, amine and hydroxyl groups as well as fluorinated chains were characterised. Study of the aggregation behaviour allowed general conclusions to be drawn regarding the influence of the introduced groups on the self-organisation of the modified copolymers. Finally, possibilities for the formation of complexes, based on electrostatic or hydrogen-bonding interactions in mixtures of block copolymers bearing mutually interacting functional groups, were investigated. N2 - Um die Prinzipien der Selbstorganisation von Blockcopolymeren zu verstehen, ist es notwendig das Wissen auf den Gebieten der Synthese und der Physikochemie zu kombinieren. Die Fähigkeit, Blockcopolymere mit gewünschter Architektur zu synthetisieren, gibt einem auch die Möglichkeit das Aggregationsverhalten zu steuern, was wiederum der Schlüssel zur Nanotechnologie ist. Abgesehen von den relativen Blockvolumina, wird die Größe und Morphologie der gebildeten Nanostrukturen durch die effektive Inkompartibilität zwischen den unterschiedlichen Blöcken bestimmt. Da die Polymerisationstechniken, mit denen man gut definierte Blockcopolymere synthetisieren kann, auf bestimmte Monomere beschränkt sind, läßt sich diese Inkompatibilität nur eingeschränkt abstimmen. Polymeranaloge Reaktionen können dagegen eine Möglichkeit bieten, funktionale Blockcopolymere durch die chemische Modifizierung von gut definierten Copolymeren zu erhalten. Somit können, bei Verwendung von geeigneten Modifikationsmethoden, die Volumenanteile sowie die Inkompatibilität der Blöcke angepasst werden. Außerdem können Copolymere, die funktionelle Gruppe enthalten, es ermöglichen das Prinzip der molekularen Erkennung (Schloss-Schlüssel) auf dem Gebiet der synthetischen Polymere anzuwenden. Die vorleigende Arbeit beschreibt einen Ansatz zur modularen Synthese von funktionalen Blockcopolymeren. Durch radikalische Addition von funktionellen Mercaptanen wurden in Copolymere mit einem Polybutadien-Block verschiedenen funktionelle Gruppen eingebracht. Von 1,2-Polybutadien-Polyethylenoxid Blockcopolymeren werden dabei mehrere Modifikationen im Detail beschrieben. Zudem wird die Erweiterung des Konzepts auf 1,2-Polybutadien-Polystyrol Blockcopolymere gezeigt. Die weiteren Untersuchungen betrafen die Selbstorganisation der modifizierten Blockcopolymere in Lösung. Hierbei wurden die Aggregate, die in wässriger Lösung von Blockcopolymeren mit Carbonsäure-, Amin- und Hydroxylgruppen sowie fluorierte Ketten gebildet werden, charakterisiert. Die Untersuchung des Aggregationsverhaltens erlaubt es, generelle Aussagen über den Einfluss der eingebrachten Gruppen auf die Selbstorganisation der modifizierten Copolymere zu treffen. Abschließend wurde die Bildung von Komplexen auf der Basis von elektrostatischer Wechselwirkung oder Wasserstoffbrückenbindung in Mischungen aus Copolymeren, die untereinander Wechselwirkende funktionale Gruppe besitzen, untersucht. T2 - Towards a library of functional block copolymers : synthesis and colloidal properties KW - Blockcopolymere KW - Funktionalisierung KW - Selbstorganisation KW - Kolloid KW - Komplexe KW - Thiole KW - block copolymers KW - functionalization KW - self-organisation KW - colloids KW - complexes Y1 - 2005 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-5907 ER - TY - GEN A1 - McQuade, D. Tyler A1 - O'Brien, Alexander G. A1 - Dörr, Markus A1 - Rajaratnam, Rajathees A1 - Eisold, Ursula A1 - Monnanda, Bopanna A1 - Nobuta, Tomoya A1 - Löhmannsröben, Hans-Gerd A1 - Meggers, Eric A1 - Seeberger, Peter H. T1 - Continuous synthesis of pyridocarbazoles and initial photophysical and bioprobe characterization N2 - Pyridocarbazoles when ligated to transition metals yield high affinity kinase inhibitors. While batch photocyclizations enable the synthesis of these heterocycles, the non-oxidative Mallory reaction only provides modest yields and difficult to purify mixtures. We demonstrate here that a flow-based Mallory cyclization provides superior results and enables observation of a clear isobestic point. The flow method allowed us to rapidly synthesize ten pyridocarbazoles and for the first time to document their interesting photophysical attributes. Preliminary characterization reveals that these molecules might be a new class of fluorescent bioprobe. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 246 KW - protein-kinase inhibitors KW - continuous-flow KW - photochemical synthesis KW - light KW - efficient KW - phenanthrenes KW - complexes Y1 - 2013 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-95214 SP - 4067 EP - 4070 ER -