The development of synthetic particles that emulate real viruses in size, shape, and chemical composition is vital to the development of imprinted polymer-based sorbent materials (molecularly imprinted polymers, MIPs). In this study, we address surrogates for adenovirus type 5 (Adv 5) via the synthesis and subsequent modification of icosahedral gold nanoparticles (iAuNPs) decorated with the most abundant protein of the Adv 5 (i.e.
View Article and Find Full Text PDFThis review critically summarizes the latest contributions in the preparation of advanced nano/microparticle-contained polymers from emulsions. The nano- or micro-particles can be dispersed in the phase where the polymerization reaction takes place and, consequently, once the solid is formed, the particles are embedded in the final polymeric structure. This results in the formation of hybrid materials, which combine the unique properties of nano/micro-particles with the inherent properties of the polymers (which depend mainly on the selected monomers).
View Article and Find Full Text PDFMolecular imprinting has proven to be a versatile and simple strategy to obtain selective materials also termed "plastic antibodies" for a wide variety of species, i.e., from ions to macromolecules and viruses.
View Article and Find Full Text PDFNanomaterials (Basel)
November 2021
The development of new methods for the rapid, sensitive, and selective detection of SARS-CoV-2 is a key factor in overcoming the global pandemic that we have been facing for over a year. In this work, we focused on the preparation of magnetic molecularly imprinted polymers (MMIPs) based on the self-polymerization of dopamine at the surface of magnetic nanoparticles (MNPs). Instead of using the whole SARS-CoV-2 virion as a template, a peptide of the viral spike protein, which is present at the viral surface, was innovatively used for the imprinting step.
View Article and Find Full Text PDFTwo types of magnetic hydrophobic solids were prepared by Pickering emulsion photopolymerization using polystyrene-modified magnetic nanoparticles (PS-MNPs) as emulsion stabilizers. Additionally, PS-MNPs provided magnetic character to the final solids. W/O Pickering emulsions were produced with high amounts of oily phase (above 50 wt%), while O/W Pickering emulsions were formed with higher amounts of aqueous phase (above 60 wt%).
View Article and Find Full Text PDFIn recent years, molecularly imprinted polymers (MIPs) have become an excellent solution to the selective and sensitive determination of target molecules in complex matrices where other similar and relative structural compounds could coexist. Although MIPs show the inherent properties of the polymers, including stability, robustness, and easy/cheap synthesis, some of their characteristics can be enhanced, or new functionalities can be obtained when nanoparticles are incorporated in their polymeric structure. The great variety of nanoparticles available significantly increase the possibility of finding the adequate design of nanostructured MIP for each analytical problem.
View Article and Find Full Text PDFHydrophilic solids based on poly(2-hydroxyethyl methacrylate) (pHEMA) with embedded magnetic nanoparticles and amine-modified carbon nanotubes were synthesized by photopolymerization. For this purpose, an oil in water (O/W) emulsion with an aqueous/oil ratio of 60/40 was prepared where the polymerization reaction occurred in the aqueous phase due to the hydrophilicity of pHEMA and the selected nanoparticles. Variables affecting the stability and emulsion formation as well as the initiation and propagation of the polymerization were studied.
View Article and Find Full Text PDFAnal Bioanal Chem
September 2020
A lab-made stirring extraction unit based on a selective monolithic solid was developed. The monolith was formed by interconnected carbon nanotubes which were covered by a thin polymeric layer, where specific cavities were generated to provide selective recognition sites in the material. To reach this goal, a water-in-oil (W/O) medium internal phase emulsion (40/60 w/w%), was prepared and photopolymerized.
View Article and Find Full Text PDFA facile and convenient approach for the preparation of interconnected multiwalled carbon nanotube (MWCNT) monolithic sorbents in recycled plastic caps has been developed. The method, which was based on the photopolymerization of the individual MWCNTs via the formation of a W/O medium internal phase emulsion (40/60 w/w%), provides control over the size of pores, rigidity, and the mechanical stability of the final solid. Pluronic L121 was used as a surfactant containing the water phase inside it and, consequently, the organic and non-polar phase, in which the MWCNTs and the cross-linker were trapped, remained on the outside of the droplets.
View Article and Find Full Text PDFA porous monolithic solid based on single-walled carbon nanohorns dahlia-like structure, produced from a medium internal phase emulsion (MIPE), was prepared in a polypropylene tip using UV energy. Thus, single-walled carbon nanohorns (SWNHs) were added to the organic phase where they polymerized in the presence of a radical initiator. A cross-linker (ethylene dimethacrylate, EDMA) was also used in order to obtain a more robust structure.
View Article and Find Full Text PDFA successful copolymerization of the single-walled carbon nanohorns (SWNHs) with methacrylate monomers was achieved via thermal initiated free-radical polymerization because of the high reactivity of the SWNHs in comparison with other carbon nanostructures. The hybrid solids were deeply characterized in terms of morphology, by scanning electron microscopy (SEM). The effect of the incorporation of the bare or oxidized (o-SWNHs) carbon nanoparticles at different percentages (0-0.
View Article and Find Full Text PDFOne-step methods for fabricating green materials endowed with diverse functions is a challenge to be overcome in terms of reducing environmental risk and cost. We report a fast and easy synthesis of multifunctional materials composed of only fluorescent dots with structural flexibility and high sorption capability. The synthesis consists of a one-pot microwave-assisted reaction for the simultaneous formation of graphene quantum dots (GQDs) from organic precursors and their spontaneous self-assembly forming porous architectures.
View Article and Find Full Text PDFThis article reviews the synthesis and uses of nanoparticle-based hybrid monoliths in microextraction techniques. Synthesizing monolithic solids containing nanoparticles allows the advantages of the two sorbent phases to be synergistically combined. The resulting hybrid material exhibits outstanding capabilities for isolating the target compounds from the samples.
View Article and Find Full Text PDFA monolithic solid based solely on single walled carbon nanohorns (SWNHs) was prepared without the need of radical initiators or gelators. The procedure involves the preparation of a wet jelly-like system of pristine SWNHs followed by slow drying (48 h) at 25 °C. As a result, a robust and stable porous network was formed due to the interaction between SWNHs not only via π-π and van der Waals interactions, but also via the formation of carbon bonds similar to those observed within dahlia aggregates.
View Article and Find Full Text PDFThis article describes a method for the modification of paper with single-wall carbon nanohorns (SWCNHs) to form stable suprastructures. The SWCNHs form stable dahlia-like aggregates in solution that are then self-assembled into superior structures if the solvent is evaporated. Dipping paper sections into a dispersion of SWCNHs leads to the formation of a thin film that can be used for microextraction purposes.
View Article and Find Full Text PDFThis work evaluates the potential of methacrylate monoliths with multi-walled carbon nanotubes incorporated into the polymeric network for the extraction of antidepressants from human urine. The method is based on a micropipette solid-phase extraction tip containing a hybrid monolithic material covalently attached to the polypropylene housing. A polymer layer made from poly(ethylene dimethacrylate) was bound to the inner surface of a polypropylene tip via UV grafting.
View Article and Find Full Text PDFThis article presents a monolithic extraction unit with integrated stirring using carbon nanohorns and methacrylate-based compounds as monomers. The hybrid monolithic material was prepared by thermal polymerization at 70 °C for 24 h, and was applied for the extraction of UV-filters from waters and human urine samples. To achieve the integrated stirring unit, the monolith was grown over an ironware.
View Article and Find Full Text PDFA novel hybrid micro and meso porous silica monolith with embedded carbon nanoparticles (Si-CNPs monolith) was prepared inside a fused silica capillary (3cm in length) and used as a sorbent for solid-phase microextraction. The hybrid monolithic capillary was synthetized by hydrolysis and polycondensation of a mixture of tetraethoxysilane (TEOS), ethanol, and three different carbon nanoparticles such as carboxylated single-walled carbon nanotubes (c-SWCNTs), carboxylated multi-walled carbon nanotubes (c-MWCNTs), and oxidized single-walled carbon nanohorns (o-SWNHs) via a two-step catalytic sol-gel process. Compared with silica monolith without carbon nanoparticles, the developed monolithic capillary column exhibited a higher extraction efficiency towards the analytes which can be ascribed to the presence of the carbon nanoparticles.
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