Export 12 results:
Sort by: Author Title Type [ Year  (Asc)]
Ribeiro N, Aguiar-Ricardo A. "A simple acoustic probe for fluid phase equilibria: Application to the CO2 + N(C2H5)3 system." Fluid Phase Equilibria. 2001;185(1-2):295-303. AbstractWebsite
Duarte CMM, Menduiña C, Aguiar-Ricardo A, Nunes Da Ponte M. "Second and third virial coefficients of three binary mixtures containing xenon, at 273 K: Comparison between Xe + C2H6, Xe + C2H4 and Xe + CO2." Physical Chemistry Chemical Physics. 2002;4(19):4709-4715. AbstractWebsite
Brás ARE, Casimiro T, CALDEIRA J, Aguiar-Ricardo A. "Solubility of the nematic liquid crystal E7 in supercritical carbon dioxide." Journal of Chemical and Engineering Data. 2005;50(6):1857-1860. AbstractWebsite
Casimiro T, Banet-Osuna AM, Ramos AM, da Ponte MN, Aguiar-Ricardo A. "Synthesis of highly cross-linked poly(diethylene glycol dimethacrylate) microparticles in supercritical carbon dioxide." European Polymer Journal. 2005;41(9):1947-1953. AbstractWebsite
Temtem M, Casimiro T, Aguiar-Ricardo A. "Solvent power and depressurization rate effects in the formation of polysulfone membranes with CO2-assisted phase inversion method." Journal of Membrane Science. 2006;283(1-2):244-252. AbstractWebsite
Duarte ARC, Casimiro T, Aguiar-Ricardo A, Simplício AL, Duarte CMM. "Supercritical fluid polymerisation and impregnation of molecularly imprinted polymers for drug delivery." Journal of Supercritical Fluids. 2006;39(1):102-106. AbstractWebsite
Temtem M, Pompeu D, Casimiro T, Mano JF, Aguiar-Ricardo A. "Supercritical CO 2 generating chitosan membranes and microparticles.". In: 8th World Biomaterials Congress 2008. Vol. 2.; 2008:. Abstract
Temtem M, Silva LMC, Andrade PZ, dos Santos F, da Silva CL, Cabral JMS, Abecasis MM, Aguiar-Ricardo A. "Supercritical CO2 generating chitosan devices with controlled morphology. Potential application for drug delivery and mesenchymal stem cell culture." Journal of Supercritical Fluids. 2009;48(3):269-277. AbstractWebsite
da Silva MS, Viveiros R, Coelho MB, Aguiar-Ricardo A, Casimiro T. "Supercritical CO2-assisted preparation of a PMMA composite membrane for bisphenol A recognition in aqueous environment." Chemical Engineering Science. 2012;68:94-100. AbstractPDFWebsite

This work reports a novel strategy to prepare affinity composite membranes using supercritical fluid technology. By blending molecularly imprinted polymeric particles with PMMA, a porous hybrid structure with affinity to the template molecule, bisphenol A, was prepared using a supercritical carbon dioxide (scCO2)-assisted method. Membranes were characterized in terms of morphology, mechanical performance and transport properties. The ability of the polymers and hybrid membranes to adsorb bisphenol A was tested in aqueous solutions and fitted to a linearized Langmuir equation, showing that adsorption takes place at homogeneous affinity binding sites within the imprinted surface. Filtration experiments showed that the imprinted hybrid membrane was able to adsorb higher amounts of template even in non-equilibrium dynamic binding conditions. The hybridization of the PMMA membrane herein reported conveys two important improvements over neat PMMA membrane: it introduced molecular affinity towards the template molecule and significantly increased the permeability of the porous structures, which are key parameters in processes that involve membranes. This technique could expand the applications of polymeric beads powders and enhance the efficiency of the membrane's transport properties. Our work presents a new method to confer affinity to a porous structure by immobilization of imprinted polymers, combining polymer synthesis and membrane formation using supercritical fluid technology.

da Silva MS, Viveiros R, Aguiar-Ricardo A, Bonifacio VDB, Casimiro T. "Supercritical fluid technology as a new strategy for the development of semi-covalent molecularly imprinted materials." RSC Adv.. 2012;2:5075-5079. AbstractPDFWebsite

Molecularly imprinted polymeric particles with molecular recognition towards Bisphenol A (BPA) were synthesized for the first time using the semi-covalent imprinting approach in supercritical carbon dioxide (scCO2). The material{'}s affinity to BPA was achieved by co-polymerizing ethylene glycol dimethacrylate (EGDMA) with a template-containing monomer{,} Bisphenol A dimethacrylate (BPADM) in scCO2. Bisphenol A is then cleaved from the polymeric matrix by hydrolysis with tetrabutylammonium hydroxide (n-Bu4OH) also in a supercritical environment{,} taking advantage of the high diffusivity of scCO2. The selectivity of the molecular imprinted polymer (MIP) was assessed by evaluating its capability to bind BPA in comparison with progesterone and [small alpha]-ethinylestradiol. In addition{,} the cross-linked particles were used to prepare a PMMA-based hybrid imprinted membrane by a scCO2-assisted phase inversion method. Results show that the incorporation of MIP particles was able to confer molecular affinity to BPA to the membrane and that at dynamic conditions of filtration{,} this imprinted porous structure was able to adsorb a higher amount of BPA than the corresponding non-imprinted hybrid membrane. Our work represents a valuable greener alternative to conventional methods{,} for the synthesis of affinity materials which are able to maintain molecular recognition properties in water.