TY  - JOUR
A1  - Kumar, Reddi K.
A1  - Heuchel, Matthias
A1  - Kratz, Karl
A1  - Lendlein, Andreas
A1  - Jankowski, Joachim
A1  - Tetali, Sarada D.
T1  - Effects of extracts prepared from modified porous poly(ether imide) microparticulate absorbers on cytotoxicity, macrophage differentiation and proinflammatory behavior of human monocytic (THP-1) cells
JF  - Clinical hemorheology and microcirculation : blood flow and vessels
N2  - Remaining uremic toxins in the blood of chronic renal failure patients represent one central challenge in hemodialysis therapies. Highly porous poly(ether imide) (PEI) microparticles have been recently introduced as candidate absorber materials, which show a high absorption capacity for uremic toxins and allow hydrophilic surface modification suitable for minimization of serum protein absorption. In this work, the effects of extracts prepared from PEI microparticles modified by nucleophilic reaction with low molecular weight polyethylene imine (Pei) or potassium hydroxide (KOH), on human monocytic (THP-1) cells are studied. The obtained results suggested that the extracts of Pei and KOH modified PEI absorbers have no negative effect on THP-1 cell viability and do not initiate the critical differentiation towards macrophages. The extracts did not enhance transcript or protein levels of investigated proinflammatory markers in THP-1 cells, namely, TNF alpha, MCP1, IL6 and IL8. Based on these findings such modified PEI microparticles should be qualified for further pre-clinical evaluation i.e. in an in vivo animal experiment.
KW  - Chronic kidney disease
KW  - hemodialysis
KW  - Inflammation
KW  - Porous poly(ether imide) microparticulate absorbers
KW  - THP-1 cells
KW  - Uremic toxins
Y1  - 2018
U6  - https://doi.org/10.3233/CH-189112
SN  - 1386-0291
SN  - 1875-8622
VL  - 69
IS  - 1-2
SP  - 175
EP  - 185
PB  - IOS Press
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Wang, Li
A1  - Razzaq, Muhammad Yasar
A1  - Rudolph, Tobias
A1  - Heuchel, Matthias
A1  - Nöchel, Ulrich
A1  - Mansfeld, Ulrich
A1  - Jiang, Yi
A1  - Gould, Oliver E. C.
A1  - Behl, Marc
A1  - Kratz, Karl
A1  - Lendlein, Andreas
T1  - Reprogrammable, magnetically controlled polymeric nanocomposite actuators
JF  - Material horizons
N2  - Soft robots and devices with the advanced capability to perform adaptive motions similar to that of human beings often have stimuli-sensitive polymeric materials as the key actuating component. The external signals triggering the smart polymers’ actuations can be transmitted either via a direct physical connection between actuator and controlling unit (tethered) or remotely without a connecting wire. However, the vast majority of such polymeric actuator materials are limited to one specific type of motion as their geometrical information is chemically fixed. Here, we present magnetically driven nanocomposite actuators, which can be reversibly reprogrammed to different actuation geometries by a solely physical procedure. Our approach is based on nanocomposite materials comprising spatially segregated crystallizable actuation and geometry determining units. Upon exposure to a specific magnetic field strength the actuators’ geometric memory is erased by the melting of the geometry determining units allowing the implementation of a new actuator shape. The actuation performance of the nanocomposites can be tuned and the technical significance was demonstrated in a multi-cyclic experiment with several hundreds of repetitive free-standing shape shifts without losing performance.
Y1  - 2018
U6  - https://doi.org/10.1039/c8mh00266e
SN  - 2051-6347
SN  - 2051-6355
VL  - 5
IS  - 5
SP  - 861
EP  - 867
PB  - Royal Society of Chemistry
CY  - Cambridge
ER  - 
TY  - JOUR
A1  - Wischke, Christian
A1  - Baehr, Elen
A1  - Racheva, Miroslava
A1  - Heuchel, Matthias
A1  - Weigel, Thomas
A1  - Lendlein, Andreas
T1  - Surface immobilization strategies for tyrosinase as biocatalyst applicable to polymer network synthesis
JF  - MRS Advances
N2  - Enzymes have recently attracted increasing attention in material research based on their capacity to catalyze the conversion of polymer-bound moieties for synthesizing polymer networks, particularly bulk hydrogels. hi this study. the surface immobilization of a relevant enzyme. mushroom tyrosinase, should be explored using glass as model surface. In a first step. the glass support was functionalized with silanes to introduce either amine or carboxyl groups, as confirmed e.g. by X-ray photoelectron spectroscopy. By applying glutaraldehyde and EDC/NHS chemistry, respectively, surfaces have been activated for subsequent successful coupling of tyrosinase. Via protein hydrolysis and amino acid characterization by HPLC, the quantity of bound tyrosinase was shown to correspond to a full surface coverage. Based on the visualized enzymatic conversion of a test substrate at the glass support. the functionalized surfaces may be explored for surface-associated material synthesis in the future.
Y1  - 2018
U6  - https://doi.org/10.1557/adv.2018.630
SN  - 2059-8521
VL  - 3
IS  - 63
SP  - 3875
EP  - 3881
PB  - Cambridge Univ. Press
CY  - New York
ER  -