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High Compatibility (high + compatibility)
Selected AbstractsElectrochemical Detection for Capillary Electrophoresis Microchips: A ReviewELECTROANALYSIS, Issue 13 2005Joseph Wang Abstract Electrochemistry detection offers considerable promise for capillary-electrophoresis (CE) microchips, with features that include remarkable sensitivity, portability, independence of optical path length or sample turbidity, low cost and power requirements, and high compatibility with modern micromachining technologies. This article highlights key strategies in controlled-potential electrochemical detectors for CE microchip systems, along with recent advances and directions. Subjects covered include the design of the electrochemical detection system, its requirements and operational principles, common electrode materials, isolation from the separation voltage, derivatization reactions, typical applications, and future prospects. It is expected that electrochemical detection will become a powerful tool for CE microchip systems and will lead to the creation of truly portable (and possibly disposable) devices. [source] High MS-compatibility of silver nitrate-stained protein spots from 2-DE gels using ZipPlates and AnchorChips for successful protein identificationELECTROPHORESIS, Issue 10 2007Grit Nebrich Abstract The availability of easy-to-handle, sensitive, and cost-effective protein staining protocols for 2-DE, in conjunction with a high compatibility for subsequent MS analysis, is still a prerequisite for successful proteome research. In this article we describe a quick and easy-to-use methodological protocol based on sensitive, homogeneous, and MS-compatible silver nitrate protein staining, in combination with an in-gel digestion, employing the Millipore 96-well ZipPlate system for peptide preparation. The improved quality and MS compatibility of the generated protein digests, as compared to the otherwise weakly MS-compatible silver nitrate staining, were evaluated on real tissue samples by analyzing 192 Coomassie-stained protein spots against their counterparts from a silver-stained 2-DE gel. Furthermore, the applicability of the experimental setup was evaluated and demonstrated by the analysis of a large-scale MALDI-TOF MS experiment, in which we analyzed an additional ,1000 protein spots from 2-DE gels from mouse liver and mouse brain tissue. [source] Solvent-Resistant PDMS Microfluidic Devices with Hybrid Inorganic/Organic Polymer CoatingsADVANCED FUNCTIONAL MATERIALS, Issue 23 2009Bo-Yeol Kim Abstract This study presents a method for the fabrication of solvent-resistant poly(dimethylsiloxane) (PDMS) microfluidic devices by coating the microfluidic channel with a hybrid inorganic/organic polymer (HR4). This modification dramatically increases the resistance of PDMS microfluidic channels to various solvents, because it leads to a significant reduction in the rate of solvent absorption and consequent swelling. The compatibility of modified PDMS with a wide range of solvents is investigated by evaluating the swelling ratio measured through weight changes in a standard block. The HR4-modified PDMS microfluidic device can be applied to the formation of water-in-oil (W/O) and oil-in-water (O/W) emulsions. The generation of organic solvent droplets with high monodispersity in the microfluidic device without swelling problems is demonstrated. The advantage of this proposed method is that it can be used to rapidly fabricate microfluidic devices using the bulk properties of PDMS, while also increasing their resistance to various organic solvents. This high compatibility with a variety of solvents of HR4-modified PDMS can expand the application of microfluidic systems to many research fields. [source] Membranes of cellulose triacetate produced from sugarcane bagasse cellulose as alternative matrices for doxycycline incorporationJOURNAL OF APPLIED POLYMER SCIENCE, Issue 6 2009Guimes Rodrigues Filho Abstract Cellulose triacetate (CTA) membranes were prepared using polyethylene glycol, 600 g mol,1, (PEG) as additive and were utilized in essays of doxycycline (DOX) incorporation using two different procedures: (i) incorporation of the drug during the membrane preparation and (ii) incorporation of the drug to a previously prepared membrane. In the first, the produced membrane presented high compatibility between DOX and CTA, what was evidenced by analyzing the DSC curve for a CTA/PEG 50%/DOX system. Results showed that the drug is homogeneously distributed throughout the matrix, molecularly. In the second method, the drug was molecularly and superficially adsorbed, as seen through the DSC curve for the system CTA/PEG 10%/DOX, which nearly does not present alterations in relation to the original material, and through the isotherm of drug adsorption that follows the Langmuir model. Results showed that the membranes produced from sugarcane bagasse are adequate to produce matrices for drug-controlled release, both for enteric use (Method (i)) and topic use (Method (ii)). © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 [source] PVC modification through polymerization of a monomer absorbed in porous suspension-type PVC particlesJOURNAL OF VINYL & ADDITIVE TECHNOLOGY, Issue 3 2004M. Narkis In-situ polymerization is the polymerization of one monomer in the presence of another polymer. It can be performed by sequential emulsion polymerization, or by reactions in the melt, in the solid phase, or in solution. The current report describes two methods to obtain poly(vinyl chloride) (PVC) modification through polymerization of a monomer absorbed in commercial porous suspension-type PVC particles. The generated modified PVC products differ significantly in their structure and properties. The first approach includes absorption of a monomer/peroxide solution within porous suspension-type PVC particles, followed by polymerization/crosslinking in the solid state at 80°C in an aqueous stabilizer-free dispersion. The monomer/crosslinker pairs selected are styrene/DVB (divinyl benzene), methylmethacrylate/EGDMA (ethylene glycol dimethacrylate), butyl acrylate/EGDMA, and ethylhexyl acrylate/EGDMA. The influence of composition and nature of the polymerizing/crosslinking constituents on the modified PVC particle structure was studied by microscopy methods, porosity measurements, and dynamic mechanical behavior (DMTA). The level of molecular grafting between PVC and the modifying polymer was determined by solvent extraction experiments. This work shows that the different monomers used represent distinct courses of monomer transport through the PVC particles. The characteristics of the modified PVC particle indicate that the polymerization/crosslinking process occurs in both the PVC bulk, i.e., within the walls constituting a particle, and in the PVC pores. No indication of chemical intermolecular interaction within the modified PVC particles was found. In the second approach, a solution of monomer, initiator, and a crosslinking agent is absorbed in commercial suspension-type porous PVC particles, thus forming a dry blend. This dry blend is subsequently reactively polymerized in a twin-screw extruder at an elevated temperature, 180°C, in the molten state. The properties of the reactively extruded PVC/PMMA blends are compared with those of physical blends at similar compositions. Owing to the high polymerization temperature, short-chain polymers are formed in the reactive polymerization process. Reactively extruded PVC/PMMA blends are transparent, form single-phase morphology, have a single Tg, and show mechanical properties comparable with those of the neat PVC. The resulting reactively extruded PVC/PMMA blends have high compatibility. J. Vinyl Addit. Technol. 10:109,120, 2004. © 2004 Society of Plastics Engineers. [source] Effect of the compatibility on toughness of injection-molded polypropylene blended with EPR and SEBSPOLYMER ENGINEERING & SCIENCE, Issue 1 2006Yushi Matsuda The effect of the compatibility between a dispersed phase and a matrix polymer and the annealing on improvement in the toughness of injection-molded isotactic polypropylene (i-PP) blended with elastomers was studied. Two grades of ethylene-propylene copolymer (EPR(A) and EPR(B)) and styrene-ethylene-butadiene-styrene tri-block copolymer (SEBS) were used as elastomer. EPR(B), which has lower strength than EPR(A), was able to improve the toughness of i-PP more effectively than EPR(A). However, SEBS, which has higher strength than EPR(B), was more effective than EPR(B). This result contradicts the toughening mechanism of relaxing the strain constraint due to void formation. Two reasons are probable. First, the volume fraction of the dispersed phase of the i-PP blended with EPR(B), hereinafter referred to as EPR(B)/i-PP, is much lower than that of the i-PP blended with SEBS (SEBS/i-PP) because of the high compatibility between EPR and i-PP. Second, it is possible that the dissolved i-PP in EPR increases the strength of the dispersed phase. In this case, the void formation from the dispersed phase is restricted. Therefore, the efficiency of toughness improvement by relaxing the strain constraint is decreased. The annealing improves the phase separation. As a result, the strength of the dispersed phase is decreased, and therefore the toughness is improved. The effect of the annealing of EPR(B)/i-PP is higher than that of SEBS/i-PP because of the high compatibility between EPR and i-PP. POLYM. ENG. SCI., 46:29,38, 2006. © 2005 Society of Plastics Engineers [source] Engineering of the ,-amylase from Geobacillus stearothermophilus US100 for detergent incorporationBIOTECHNOLOGY & BIOENGINEERING, Issue 2 2009Bassem Khemakhem Abstract AmyUS100,IG is a variant of the most thermoactive and thermostable maltohexaose forming ,-amylase produced by Geobacillus stearothermophilus sp.US100. This enzyme which was designed to improve the thermostability of the wild-type enzyme has acquired a very high resistance to chelator agents. According to modeling structural studies and with the aim of enhancing its resistance towards chemical oxidation, a mutant (AmyUS100,IG/M197A) was created by substituting methionine 197 to alanine. The catalytic proprieties of the resulting mutant show alterations in the specific activity and the profile of starch hydrolysis. Interestingly, AmyUS100,IG/M197A displayed the highest resistance to oxidation compared to the AmyUS100,IG and to Termamyl300®, the well-known commercial amylase used in detergent. Further, performance of the engineered ,-amylase was estimated in the presence of commonly used detergent compounds and a wide range of commercial detergent (liquid and solid). These studies indicated a high compatibility and performance of AmyUS100,IG/M197A, suggesting its potential application in detergent industry. Biotechnol. Bioeng. 2009;102: 380,389. © 2008 Wiley Periodicals, Inc. [source] Ion-Exchange Plasma Membranes for Fuel Cells on a Micrometer Scale,CHEMICAL VAPOR DEPOSITION, Issue 6-7 2007S. Roualdès Abstract Recent advances in,miniaturization technology make polymer electrolyte membrane fuel cells very attractive as power sources for portable devices. Ion-exchange membranes for microscale fuel cells are synthesized by plasma polymerization (using a precursor containing ion-exchange groups) and intensively characterized. Ion-exchange plasma membranes are thin, amorphous, and dense materials with no defects. Spectroscopic analyses reveal a polymer-type matrix containing a rather high concentration of ion-exchange groups. Under the best synthesis conditions, membranes show a satisfying ionic conduction level and a high compatibility with other active layers of fuel cells, making them suitable for insertion in such power-supply devices. [source] | |||||||||||||||||||||||||