Publications

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2013
Correia VG, Coelho M, Barroso T, Raje VP, Bonifácio VDB, Casimiro T, Pinho MG, Aguiar-Ricardo A. "Anti-biofouling 3D porous systems: the blend effect of oxazoline-based oligomers on chitosan scaffolds." Biofouling. 2013;29(3):273-282. AbstractWebsite
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Reis TC, Correia IJ, Aguiar-Ricardo A. "Electrodynamic tailoring of self-assembled three-dimensional electrospun constructs." Nanoscale. 2013;5(16):7528-7536. AbstractWebsite
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Barroso T, Hussain A, Roque ACA, Aguiar-Ricardo A. "Functional monolithic platforms: Chromatographic tools for antibody purification." Biotechnology Journal. 2013;8(6):671-681. AbstractWebsite
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Raje VP, Morgado PI, Ribeiro MP, Correia IJ, Bonifácio VDB, Branco PS, Aguiar-Ricardo A. "Dual on–off and off–on switchable oligoaziridine biosensor." Biosensors and Bioelectronics. 2013;39:64-69. AbstractWebsite
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2012
Barroso T, Roque ACA, Aguiar-Ricardo A. "Bioinspired and sustainable chitosan-based monoliths for antibody capture and release." RSC Advances. 2012;2(30):11285-11294. AbstractWebsite
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Bonifácio VDB, Correia VG, Pinho MG, Lima JC, Aguiar-Ricardo A. "Blue emission of carbamic acid oligooxazoline biotags." Materials Letters. 2012;81:205-208. AbstractWebsite
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Temtem M, Barroso T, Casimiro T, Mano JF, Aguiar-Ricardo A. "Dual stimuli responsive poly(N-isopropylacrylamide) coated chitosan scaffolds for controlled release prepared from a non residue technology." Journal of Supercritical Fluids. 2012;66:398-404. AbstractWebsite
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Costa E, Lloyd MM, Chopko C, Aguiar-Ricardo A, Hammond PT. "Tuning Smart Microgel Swelling and Responsive Behavior through Strong and Weak Polyelectrolyte Pair Assembly." LangmuirLangmuir. 2012;28(26):10082-10090. AbstractWebsite

The layer-by-layer (LbL) assembly of polyelectrolyte pairs on temperature and pH-sensitive cross-linked poly(N-isopropylacrylamide)-co-(methacrylic acid), poly(NIPAAm-co-MAA), microgels enabled a fine-tuning of the gel swelling and responsive behavior according to the mobility of the assembled polyelectrolyte (PE) pair and the composition of the outermost layer. Microbeads with well-defined morphology were initially prepared by synthesis in supercritical carbon dioxide. Upon LbL assembly of polyelectrolytes, interactions between the multilayers and the soft porous microgel led to differences in swelling and thermoresponsive behavior. For the weak PE pairs, namely poly(l-lysine)/poly(l-glutamic acid) and poly(allylamine hydrochloride)/poly(acrylic acid), polycation-terminated microgels were less swollen and more thermoresponsive than native microgel, whereas polyanion-terminated microgels were more swollen and not significantly responsive to temperature, in a quasi-reversible process with consecutive PE assembly. For the strong PE pair, poly(diallyldimethylammonium chloride)/poly(sodium styrene sulfonate), the differences among polycation and polyanion-terminated microgels are not sustained after the first PE bilayer due to extensive ionic cross-linking between the polyelectrolytes. The tendencies across the explored systems became less noteworthy in solutions with larger ionic strength due to overall charge shielding of the polyelectrolytes and microgel. ATR FT-IR studies correlated the swelling and responsive behavior after LbL assembly on the microgels with the extent of H-bonding and alternating charge distribution within the gel. Thus, the proposed LbL strategy may be a simple and flexible way to engineer smart microgels in terms of size, surface chemistry, overall charge and permeability.The layer-by-layer (LbL) assembly of polyelectrolyte pairs on temperature and pH-sensitive cross-linked poly(N-isopropylacrylamide)-co-(methacrylic acid), poly(NIPAAm-co-MAA), microgels enabled a fine-tuning of the gel swelling and responsive behavior according to the mobility of the assembled polyelectrolyte (PE) pair and the composition of the outermost layer. Microbeads with well-defined morphology were initially prepared by synthesis in supercritical carbon dioxide. Upon LbL assembly of polyelectrolytes, interactions between the multilayers and the soft porous microgel led to differences in swelling and thermoresponsive behavior. For the weak PE pairs, namely poly(l-lysine)/poly(l-glutamic acid) and poly(allylamine hydrochloride)/poly(acrylic acid), polycation-terminated microgels were less swollen and more thermoresponsive than native microgel, whereas polyanion-terminated microgels were more swollen and not significantly responsive to temperature, in a quasi-reversible process with consecutive PE assembly. For the strong PE pair, poly(diallyldimethylammonium chloride)/poly(sodium styrene sulfonate), the differences among polycation and polyanion-terminated microgels are not sustained after the first PE bilayer due to extensive ionic cross-linking between the polyelectrolytes. The tendencies across the explored systems became less noteworthy in solutions with larger ionic strength due to overall charge shielding of the polyelectrolytes and microgel. ATR FT-IR studies correlated the swelling and responsive behavior after LbL assembly on the microgels with the extent of H-bonding and alternating charge distribution within the gel. Thus, the proposed LbL strategy may be a simple and flexible way to engineer smart microgels in terms of size, surface chemistry, overall charge and permeability.

Restani RB, Morgado PI, Ribeiro MP, Correia IJ, Aguiar-Ricardo A, Bonifácio VDB. "Biocompatible Polyurea Dendrimers with pH-Dependent Fluorescence." Angewandte Chemie International Edition. 2012;51:5162-5165. AbstractWebsite

Biocompatible and biodegradable water-soluble dendrimers comprising ureas within the interior and amino groups on the periphery were synthesized in supercritical carbon dioxide (dendrimer of generation 1 shown in picture). This novel class of dendrimers shows a pH-dependent intrinsic blue fluorescence at very low concentrations, which makes them potential polymeric fluorescent cell markers.

Barroso T, Viveiros R, Temtem M, Casimiro T, Botelho do Rego AM, Aguiar-Ricardo A. "A Combined Strategy to Surface-Graft Stimuli-Responsive Hydrogels Using Plasma Activation and Supercritical Carbon Dioxide." ACS Macro Letters. 2012;1:356-360. AbstractWebsite

Differently shaped polymeric matrices were efficiently coated with stimuli-responsive hydrogels for a wide range of applications using a new methodology. By combining plasma surface activation and polymerization in supercritical media at mild conditions, we report the direct smart coating of microcarriers and membranes in gram-scale quantities with a scalable, green, and low-cost approach.

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.

Barroso T, Viveiros R, Coelho M, Casimiro T, Botelho do Rego AM, Aguiar-Ricardo A. "Influence of poly(N-isopropylacrylamide) and poly(N,N′-diethyl acrylamide) coatings on polysulfone/polyacrylonitrile-based membranes for protein separation." Polymers for Advanced Technologies. 2012;23:1381-1393. AbstractWebsite

Herein we describe the design and the assembly of temperature sensitive polysulfone (PS)/polyacrylonitrile (PAN) blend membranes using supercritical fluid technology. Blended membranes were prepared using the CO2-assisted phase inversion method, and their pores were coated with two thermoresponsive hydrogels-poly(N-isopropylacrylamide) (PNIPAAm) and poly(N,N′-diethylacrylamide) (PDEAAm). Permeation experiments of bovine serum albumin (BSA) and lysozyme (LYS) solutions were used to evaluate the performance and temperature-responsive behavior of coated membranes. While membranes coated with PNIPAAm presented similar protein permeation profiles at temperatures below and above its lower critical solution temperature, PDEAAm coating imparted a temperature-responsive behavior to PS/PAN (90:10) membranes and selective permeation of proteins with different sizes. Copyright © 2011 John Wiley & Sons, Ltd.

2011
Barroso T, Temtem M, Casimiro T, Aguiar-Ricardo A. "Antifouling performance of poly(acrylonitrile)-based membranes: From green synthesis to application." Journal of Supercritical Fluids. 2011;56(3):312-321. AbstractWebsite
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Da Silva MS, Viveiros R, Morgado PI, Aguiar-Ricardo A, Correia IJ, Casimiro T. "Development of 2-(dimethylamino)ethyl methacrylate-based molecular recognition devices for controlled drug delivery using supercritical fluid technology." International Journal of Pharmaceutics. 2011;416(1):61-68. AbstractWebsite
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Da Silva MS, Nobrega FL, Aguiar-Ricardo A, Cabrita EJ, Casimiro T. "Development of molecularly imprinted co-polymeric devices for controlled delivery of flufenamic acid using supercritical fluid technology." Journal of Supercritical Fluids. 2011;58(1):150-157. AbstractWebsite
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Correia VG, Bonifácio VD, Raje VP, Casimiro T, Moutinho G, da Silva CL, Pinho MG, Aguiar-Ricardo A. "Oxazoline-Based Antimicrobial Oligomers: Synthesis by CROP Using Supercritical CO 2." Macromolecular Bioscience. 2011;11(8):1128-1137. AbstractWebsite
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Costa E, De-Carvalho J, Casimiro T, da Silva CL, Cidade MT, Aguiar-Ricardo A. "Tailoring thermoresponsive microbeads in supercritical carbon dioxide for biomedical applications." Journal of Supercritical Fluids. 2011;56(3):292-298. AbstractWebsite
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Costa E, Coelho M, Ilharco LM, Aguiar-Ricardo A, Hammond PT. "Tannic acid mediated suppression of PNIPAAm microgels thermoresponsive behavior." Macromolecules. 2011;44(3):612-621. AbstractWebsite
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2010
Da Silva MS, Vão ER, Temtem M, Mafra L, CALDEIRA J, Aguiar-Ricardo A, Casimiro T. "Clean synthesis of molecular recognition polymeric materials with chiral sensing capability using supercritical fluid technology. Application as HPLC stationary phases." Biosensors and Bioelectronics. 2010;25(7):1742-1747. AbstractWebsite
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Restani RB, Correia VG, Bonifácio VDB, Aguiar-Ricardo A. "Development of functional mesoporous microparticles for controlled drug delivery." Journal of Supercritical Fluids. 2010;55(1):333-339. AbstractWebsite
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Barroso T, Viveiros R, Costa E, Temtem M, Casimiro T, Aguiar-Ricardo A. "Development of switchable "smart" biomaterials using an environmental friendly technology.". In: Materials Research Society Symposium Proceedings. Vol. 1220.; 2010:. Abstract
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Barroso T, Temtem M, Hussain A, Aguiar-Ricardo A, Roque ACA. "Preparation and characterization of a cellulose affinity membrane for human immunoglobulin G (IgG) purification." Journal of Membrane Science. 2010;348(1-2):224-230. AbstractWebsite
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2009
Temtem M, Pompeu D, Barroso T, Fernandes J, Simões PC, Casimiro T, Botelho Do Rego AM, Aguiar-Ricardo A. "Development and characterization of a thermoresponsive polysulfone membrane using an environmental friendly technology." Green Chemistry. 2009;11(5):638-645. AbstractWebsite
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