Reading out the temperature-memory of polymers, which is their ability to remember the temperature where they were deformed recently, is thus far unavoidably linked to erasing this memory effect. Here temperature-memory polymer actuators (TMPAs) based on cross-linked copolymer networks exhibiting a broad melting temperature range (ΔT m ) are presented, which are capable of a long-term temperature-memory enabling more than 250 cyclic thermally controlled actuations with almost constant performance. The characteristic actuation temperatures T act s of TMPAs can be adjusted by a purely physical process, guiding a directed crystallization in a temperature range of up to 40°C by variation of the parameter T sep in a nearly linear correlation. The temperature T sep divides ΔT m into an upper T m range (T > T sep ) forming a reshapeable actuation geometry that determines the skeleton and a lower T m range (T < T sep ) that enables the temperature-controlled bidirectional actuation by crystallization-induced elongation and melting-induced contraction. The macroscopic bidirectional shape changes in TMPAs could be correlated with changes in the nanostructure of the crystallizable domains as a result of in situ Xray investigations. Potential applications of TMPAs include heat engines with adjustable rotation rate and active building facades with self-regulating sun protectors.reversible shape-memory polymer | active movement T he alignment and coupling of thermally controlled volume changes on the nanoscale has emerged as most important working principle to translate shape changes from the nanolevel to the macrolevel in polymers (1-4). In stimuli-responsive polymers capable of a free-standing shape-changing effect, this alignment is achieved during synthesis or processing by either application of external stress or the utilization of templates and fixed by covalent cross-links (5-12). Once synthesis is completed, the geometry of the shape change cannot be changed anymore (13-15) and the actuation temperature is fixed; this relies on thermal transitions with a defined temperature. Here we explored whether it is possible to implement a thermally controlled bidirectional actuation into free-standing polymers by purely physical manipulation enabling to adjust (repeatedly) the actuation temperature and (shape changing) geometry.Although programmable shape changes have been realized in shape-memory polymers (SMPs), this effect is generally a onetime, one-way effect in free-standing SMPs (16-18). In SMPs the switching domains, which can solidify by crystallization or vitrification, provide two functions: they determine the geometry of the shape change and cause the entropy elastic recovery. A reversible movement could be observed when polymers with crystallizable segments are held under an externally applied constant stress (3,8). Recently temperature-memory polymers (TMPs) enabled the programming of the switching temperature (19,20). Also this temperature-memory effect (TME) is limited to a onetime, one-way effect. The aim of th...

Vascular endothelial growth factor type protein (VEGF), a potent angiogenic effector molecule, was successfully covalently immobilized onto the surfaces of the resorbable polymers poly(L‐lactic acid) (PLLA) and poly(ε‐caprolactone) (PCL) through a three‐step strategy. The surfaces were first covalently grafted with poly(acrylic acid) using non‐destructive and solvent free vapor‐phase grafting. A diamine spacer was coupled to the carboxylic acid pendant groups on the graft chains using EDC/NHS chemistry and VEGF was finally covalently attached to the amine linkers. The chemistry and topography of the modified substrates were quantitatively and qualitatively verified with XPS, ATR‐FTIR, UV–VIS, SEM, and ELISA. Copyright © 2010 John Wiley & Sons, Ltd.

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1. The metabolism of Meloxicam (ME) and the cytochrome(s) P450 (CYPs) involved were analysed by using primary human hepatocytes, human liver microsomes and microsomes from recombinant human B-lymphoblastoid cell lines. 2. While human hepatocytes were capable of converting ME to a 5-hydroxymethyl metabolite (M7) and then to a 5-carboxyderivative (M5), human liver microsomes formed mostly only the 5-hydroxymethylderivative. The kinetics of the formation of M7 by human liver microsomes were biphasic with Km = 13.6 +/- 9.5 and 381 +/- 55.2 microM respectively. The corresponding Vmax were 33.7 +/- 24.2 and 143 +/- 83.9 pmol/min/mg protein respectively. 3. CYP2C9 and, to a much lesser extent, CYP3A4 were found to convert ME to M7. The involvement of 2C9 was demonstrated by inhibition of tolbutamide hydroxylase activity in the presence of ME, inhibition of ME metabolism by sulphaphenazole, correlation between ME metabolism and tolbutamide hydroxylase activity and active metabolism of ME by recombinant 2C9. The involvement of 3A4 was shown by inhibition of ME metabolism by ketoconazole, correlation between ME metabolism and nifedipine oxidase activity and metabolism of ME by recombinant 3A4. Kinetics of the formation of M7 by the individual enzymes resulted in a Km = 9.6 microM and Vmax = 8.4 pmol/min/mg protein for 2C9 and a Km = 475 microM and Vmax = 23 pmol/min/mg protein for 3A4.