PHEMA grafts

Fig.44 (left) Dry thickness (in nm) of a poly(2-hydroxyethyl methacrylate) (PHEMA) brush in an orthogonal gradient as a function of the PHEMA grafting density and molecular weight The scale represents the thickness of dry polymer (in nm). (right) Adsorbed amount of lysozyme as a fimction of the position on the orthogonal PHEMA gradient. The scale represents the fluorescence intensity (in a.u.). (Reproduced with permission from [164])... 

Plot of molecular weight Mpui vs elution volume v for pullulans (filled squares and solid curve) and proteins (open circles) eluted through the PHEMA-grafted monolithic column. The molecular weights of the proteins are the reduced values independently determined by pullulan-calibrated GPC. The arrow head shows the so-called ghost peak of the eluent. The flow rate was 0.2 ml/min with PBS as eluent at room temperature. The inset shows a cartoon illustrating two size-exclusion modes of the brush-modified monolith. 

When these proteins were injected into the BHE-immobilized column (without PHEMA brush), no elution peak was observed. On the other hand, all the proteins injected into the PHEMA-grafted... 

The Mpui value is plotted against the elution volume v for each protein in Figure 11.2b. The data for the largestfour proteins fell on the pullulan-elution curve, suggesting no affinity interaction with the PHEMA-grafted column. More specifically, those large proteins were almost all excluded from the brush layer, separated only in the size-exclusion mode by the mesopores without... 

Collagen immobilization onto a silicone rubber surface which underwent plasma-induced graft polymerization of PHEMA was also reported to have improved attachment and growth of corneal epithelial cells onto the rubber surface [48,50,182]. 

These suppressive effects of SA copolymers on cellular adsorption and shape change were observed for rat lymphocytes as well as platelets (58,59). Figure 2 clearly demonstrates the elimination of adsorption of lymphocytes on albuminated surfaces of SA copolymers containing 9 wt% polyamine branches (SA9). A change in the back-bone structure of the graft copolymer from polystyrene to the more hydrophilic poly(2-hydroxyethyl methacrylate) (PHEMA)... 

Surface radicals produced in the exposed areas may also serve directly as polymerization initiators. However, their concentration will not be very high because they may be rapidly deactivated at the relatively high temperatures reached locally and because of possible reaction with volatile reaction products. Still, it was reported that poly(hydroxyethyl methacrylate) (PHEMA) could be grafted from PDMS surfaces treated with a C02-pulsed laser via the peroxide route [10]. However, the capability of the method to obtain surface structures was not explored in this case. 

Figure 4.12 Effect of grafting PHEMA and PPEGMA on PU surfaces. (Top) Reduced microfouling—that is, bacterial cell viability on surface grafted with PHEMA and PPEGMA compared to pristine PU and PU with covalently bound macroinitiator (PU-Br). (Bottom) Reduced macrofoulmg—that is, reduction m the amount of settled, live barnacle cyprids. Source Adapted from Pranantyo et al. [24], with permission from RSC Publishing.

Akgol, S. et al., Immobilization of catalase via adsorption onto L-histidine grafted functional pHEMA based membrane, J. Mol. Catal. B Enzym., 15, 197, 2001. 

The living nature of CNT-initiated ATRP promised block copolymerization from CNT surfaces. Kong et al. first conducted ATRP of hydroxyethyl methacrylate (HEMA) using PMMA-grafted MWCNTs as the initiator and CuBr/PMDETA as the catalyst to prepare PHEMA-i-PMMA-grafted MWCNTs in DMF at 60 °C for 20 h. A representative TEM image is shown... 

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