Substrate-independent approach for polymer brush growth by surface atom transfer radical polymerization

A simple method for growing polymer brushes by atom transfer radical polymerization (ATRP) off solid surfaces has been devised. This entails pulsed plasmachemical deposition of a halogen-containing initiator layer, followed by either organic or aqueous phase controlled surface polymerization. The wide-scale applicability of this approach is exemplified by functionalizing flat substrates, microbeads, and nonwoven textiles.     

Functionalization of solid surfaces with thermoresponsive protein-resistant films

Pulsed plasma polymerization of N-isopropylacrylamide leads to the deposition of thermoresponsive films. The reversible (switching) behavior of these poly(N-isopropylacrylamide) surfaces has been exemplified by screening the adsorption of fibrinogen and fluorescein isothiocyanate labeled bovine serum albumin proteins by surface plasmon resonance (SPR) and fluorescence microscopy at low and elevated temperatures.     

Poly(N-acryloylsarcosine methyl ester) protein-resistant surfaces

A new class of protein-resistant film based on N-substituted glycine derivatives is described. Pulsed plasma deposited poly(N-acryloylsarcosine methyl ester) coatings are shown to be resistant toward the adsorption of fibrinogen and lysozyme. Deposition and UV irradiation of the polymer through a masked grid are found to be effective ways for generating negative and positive image protein arrays, respectively, onto a range of different substrate materials.     

Synthesis of deuterium labelled L- and D-glutamate semialdehydes and their evaluation as substrates for carboxymethylproline synthase (CarB)--implications for carbapenem biosynthesis

Carboxymethylproline synthase was shown to condense L-glutamate semialdehyde with malonyl-coenzyme A to produce (2S,5S)-carboxymethylproline, while incubation of D-glutamate semialdehyde results only in uncoupled turnover of malonyl-CoA.     

Infrared measurements and calculations on H2O.HO

We have measured the infrared spectrum of H2O.HO in argon matrices at 11.5 +/- 0.5 K. We have also calculated the vibrational frequencies and intensities of the H2O.HO complex. As a result of these measurements and calculations, we have assigned a previously unassigned absorption band at 3442.1 cm-1 to the OH stretch in the radical complexed to the water molecule. This absorption originates from a complex that is situated in a different site within the argon matrix to those absorptions already assigned to this vibration at 3452.2 and 3428.0 cm-1. We observe a decrease in intensity of the OH radical stretching vibration of the H2O.HO complex upon isotopic substitution of D for H that agrees well with our calculations.     

An Investigation of the N-Arylsulfonylation of 2-Azetidinones

N-Arylsulfonylation of 2-azetidinones can lead to the diastereoselective formation of oligomerization products. However, a simple increase of arylsulfonyl chloride concentration minimized oligomerization and allowed preparation of 1-arylsulfonyl-2-azetidinones in good yield.     

Multi‐material incompressible flow simulation using the moment‐of‐fluid method

This paper compares the numerical performance of the moment‐of‐fluid (MOF) interface reconstruction technique with Youngs, LVIRA, power diagram (PD), and Swartz interface reconstruction techniques in the context of a volume‐of‐fluid (VOF) based finite element projection method for the numerical simulation of variable‐density incompressible viscous flows. In pure advection tests with multiple materials MOF shows dramatic improvements in accuracy compared with the other methods. In incompressible flows where density differences determine the flow evolution, all the methods perform similarly for two material flows on structured grids. On unstructured grids, the second‐order MOF, LVIRA, and Swartz methods perform similarly and show improvement over the first‐order Youngs' and PD methods. For flow simulations with more than two materials, MOF shows increased accuracy in interface positions on coarse meshes. In most cases, the convergence and accuracy of the computed flow solution was not strongly affected by interface reconstruction method. Published in 2009 by John Wiley & Sons, Ltd.     

Structural and mechanistic studies on γ-butyrobetaine hydroxylase

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Highlights? Crystal structure of γ-butyrobetaine hydroxylase in complex with substrate and inhibitor ? N-terminal Zn-binding domain involved in dimerization ? The clinically used inhibitor, THP, is also a substrate for BBOX ? BBOX catalyzed rearrangement reaction