Berlin, Germany
Berlin, Germany

Time filter

Source Type

Eichhorn T.,Danube University Krems | Ivanov A.E.,Protista Biotechnology AB | Dainiak M.B.,Protista Biotechnology AB | Leistner A.,Polymerics GmbH | And 5 more authors.
Journal of Chemistry | Year: 2013

Composite monolithic adsorbents were prepared by the incorporation of neutral polystyrene divinylbenzene (PS-DVB) microparticles into macroporous polymer structures produced by cryogelation of agarose or poly(vinyl alcohol). The composite materials exhibited excellent flow-through properties. Scanning electron microscopy of the composite cryogels revealed that the microparticles were covered by thin films of poly(vinyl alcohol) or agarose and thus were withheld in the monolith structure. Plain PS-DVB microparticles showed efficient adsorption of albumin-bound toxins related to liver failure (bilirubin and cholic acid) and of cytokines (tumor necrosis factor-alpha and interleukin-6). The rates of adsorption and the amount of adsorbed factors were lower for the embedded microparticles as compared to the parent PS-DVB microparticles, indicating the importance of the accessibility of the adsorbent pores. Still, the macroporous composite materials showed efficient adsorption of albumin-bound toxins related to liver failure as well as efficient binding of cytokines, combined with good blood compatibility. Thus, the incorporation of microparticles into macroporous polymer structures may provide an option for the development of adsorption modules for extracorporeal blood purification. © 2013 Tanja Eichhorn et al.


Savina I.N.,University of Brighton | English C.J.,University of Brighton | Whitby R.L.D.,University of Brighton | Zheng Y.,University of Brighton | And 3 more authors.
Journal of Hazardous Materials | Year: 2011

Novel nanocomposite materials where iron nanoparticles are embedded into the walls of a macroporous polymer were produced and their efficiency for the removal of As(III) from aqueous media was studied. Nanocomposite gels containing α-Fe 2O 3 and Fe 3O 4 nanoparticles were prepared by cryopolymerisation resulting in a monolithic structure with large interconnected pores up to 100μm in diameter and possessing a high permeability (ca. 3×10 -3ms -1). The nanocomposite devices showed excellent capability for the removal of trace concentrations of As(III) from solution, with a total capacity of up to 3mg As/g of nanoparticles. The leaching of iron was minimal and the device could operate in a pH range 3-9 without diminishing removal efficiency. The effect of competing ions such as SO 4 2- and PO 4 3- was negligible. The macroporous composites can be easily configured into a variety of shapes and structures and the polymer matrix can be selected from a variety of monomers, offering high potential as flexible metal cation remediation devices. © 2011 Elsevier B.V.


Siebler D.,BAM Federal Institute of Materials Research and Testing | Rohwetter P.,BAM Federal Institute of Materials Research and Testing | Brusenbach R.,TU Berlin | Lothongkam C.,BAM Federal Institute of Materials Research and Testing | And 3 more authors.
POF 2014 - 23rd International Conference on Plastic Optical Fibers, Proceedings | Year: 2014

A new fluorescent polymer optical fibre sensor (F-POF) has been tested in combination with different single photon counting modules in real-scale model of a translucent high voltage (HV) stress cone for the detection of inner partial discharges (PDs). In experiments with different artificial PD sources these sensors were capable to detect discharges with an apparent charge down to the limit of a few hundred femto Coulombs even with an unfavorable sensor location. By combining the datasets of the electrical and optical PD measurement (coincidence window ±100 ns) it is possible to suppress background noise and to undoubtedly assign signals to real inner PD events. First results of an optical/optical coincident PD measurement (coincidence interval ±100 ns) including an AC phase-correlated filtering show several coincident photon counts in the range of 1-2 pC over the whole observation interval, indicating the potential of this new alternative PD measurement and evaluation method. © 2014 ICPOF.


Hajizadeh S.,Lund University | Kirsebom H.,Lund University | Leistner A.,Polymerics GmbH | Mattiasson B.,Lund University
Journal of Separation Science | Year: 2012

Composite cryogels containing porous adsorbent particles were prepared under cryogelation conditions. The composites with immobilized concanavalin A (Con A) were used for capturing glycoproteins. Adsorbent particles were introduced into the structure in order to improve the capacity and to facilitate the handling of the particles. The monolithic composite cryogels were produced from suspensions of polyvinyl alcohol particles and porous adsorbent particles and cross-linked under acidic conditions at sub-zero temperature. The cryogels were epoxy activated and Con A was immobilized as an affinity ligand. Binding and elution of horseradish peroxidase (HRP) was studied in batch experiment and in a chromatographic setup. Increasing adsorbent concentration in composite cryogels will increase ligand density, which therefore enhances the amount of bound HRP from 0.98 till 2.9 (milligram enzyme per milliliter of gel) in the chromatographic system. The material was evaluated in 10 cycles for binding and elution of HRP. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Tripisciano C.,Danube University Krems | Leistner A.,Polymerics GmbH | Linsberger I.,Danube University Krems | Falkenhagen D.,Danube University Krems | Weber V.,Danube University Krems
Biomacromolecules | Year: 2012

In liver failure, hydrophobic toxins accumulate in the blood circulation. To support hepatic function, extracorporeal blood purification systems have been developed, in which both cationic and neutral adsorbents are used to remove albumin-bound metabolites from blood. An issue of these systems is the additional removal of coagulation factors containing negatively charged γ-carboxyglutamate (Gla) domains, which, in physiological conditions, are shielded by calcium ions. We hypothesized that complexation of calcium ions by citrate leads to exposure of negative Gla domains, resulting in their binding to the positively charged adsorbents. The data presented here confirm that the binding of coagulation factors containing Gla domains to positively charged polymers is enhanced in the presence of citrate as compared to heparin. This effect increased with increasing charge density of the polymer and has important implications for the clinical application of positively charged polymers. © 2012 American Chemical Society.

Loading Polymerics GmbH collaborators
Loading Polymerics GmbH collaborators