Protein-Mimetic, Molecularly Imprinted Nanoparticles for Selective Binding of Bile Salt Derivatives in Water

A tripropargylammonium surfactant with a methacrylate-terminated hydrophobic tail was combined with a bile salt derivative, divinyl benzene (DVB), and a photo-cross-linker above its critical micelle concentration (CMC). Surface-cross-linking with a diazide, surface-functionalization with an azido sugar derivative, and free-radical-core-cross-linking under UV irradiation yielded molecularly imprinted nanoparticles (MINPs) with template-specific binding pockets. The MINPs resemble protein receptors in size, complete water-solubility, and tailored binding sites in their hydrophobic cores. Strong and selective binding of bile salt derivatives was obtained, depending on the cross-linking density of the system

Development of a high throughput synthesis technique for the optimization of MIPs for 17β-Estradiol

ABSTRACTA high throughput synthesis technique was developed for the combinatorial optimization of polymers imprinted with 17□-Estradiol. This incorporated a liquid handling robot for the rapid dispensing of monomers, templates, solvents and initiator into the reaction vessels of a 96-well plate. A library of 80 polymers, each ca 80mg, was prepared using functional monomers containing acid functionalities (methacrylic acid (MAA), trifluoromethylacrylic acid (TFMAA)), basic functionalities (2-vinylpyridine (2-Vpy), 4-vinylpyridine (4-Vpy), diethyl-2-aminoethylmethycrylate (DEAEMA)) or neutral functional groups (2-hydroxyethylmethacrylate (HEMA), methacrylamide (MAAM), N-vinylpyrrolidone (NVP), acetoxystyrene (AST)). Four replicas each of imprinted and nonimprinted polymers were made for each functional monomer using ethyleneglycoldimethacrylate (EDMA) as crosslinking monomer and acetonitrile as solvent. Polymer washing and exchange of incubation solutions could be effectively carried out after transfer of the polymers to solvent resistant filter plates. The binding properties of the polymers could then be rapidly assessed in the batch mode by quantifying non-bound fractions in parallel using a fluorescence monochromator plate reader. These data showed an acceptable agreement with the data from a corresponding HPLC evaluation of the rebinding solutions. In agreement with other reports, the acid functional monomers MAA and TFMAA, the basic DEAEMA and the neutral MAAM exhibited the highest imprinting factors.</jats:p

Quantification of the torrefaction effects on the grindability and the hygroscopicity of wood chips

International audienceIn the field of biomass torrefaction, lots of product properties have been widely investigated at the lab scale but some uncertainties remain about the gains in terms of grindability and hygroscopicity of torrefied products. In this study, beech wood chips (with an initial moisture content of 10-12%) have been torrefied in a pilot-scale rotary kiln. The torrefaction severity was controlled by adjusting the temperature, the treatment duration and the solid hold-up in the kiln. Mass losses ranging between 1.7% and 25% have been obtained. Properties of torrefied wood chips were then analyzed in terms of composition, heat content, hygroscopicity and grinding energy requirement. Dynamic vapor sorption measurements show that a minimum of hygroscopicity is reached for a mass loss (ML) between 1.7 and 7.8%. The moisture uptakes for mass losses above this optimum remain stable at values twice lower than that of raw biomass. Finally, a new method is proposed to estimate the grindability of wood chips. This method takes into account the grinding energy consumption and the particle size distribution of ground samples. A reduction by a factor of 6.3 of the apparent specific surface grinding energy is observed between a moisture content of 41% and the dryness. This energy measurement is in turn reduced by a further factor of 8.1 after torrefaction with a 25% mass loss