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1.
Int J Mol Sci ; 22(7)2021 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-33808501

RESUMEN

In this research, we prepared foam scaffolds based on poly(l-lactide) (PLLA) and apatite whiskers (HAP) using thermally induced phase separation technique supported by the salt leaching process (TIPS-SL). Using sodium chloride having a size of (a) 150-315 µm, (b) 315-400 µm, and (c) 500-600 µm, three types of foams with different pore sizes have been obtained. Internal structure of the obtained materials has been investigated using SEM as well as µCT. The materials have been studied by means of porosity, density, and compression tests. As the most promising, the composite prepared with salt size of 500-600 µm was prepared also with the l-lysine modified apatite. The osteoblast hFOB 1.19 cell response for the scaffolds was also investigated by means of cell viability, proliferation, adhesion/penetration, and biomineralization. Direct contact cytotoxicity assay showed the cytocompatibility of the scaffolds. All types of foam scaffolds containing HAP whiskers, regardless the pore size or l-lysine modification induced significant stimulatory effect on the cal-cium deposits formation in osteoblasts. The PLLA/HAP scaffolds modified with l-lysine stimulated hFOB 1.19 osteoblasts proliferation. Compared to the scaffolds with smaller pores (150-315 µm and 315-400 µm), the PLLA/HAP foams with large pores (500-600 µm) promoted more effective ad-hesion of osteoblasts to the surface of the biomaterial.


Asunto(s)
Durapatita/química , Poliésteres/química , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Apatitas/química , Apatitas/metabolismo , Materiales Biocompatibles/química , Línea Celular Tumoral , Humanos , Ácido Láctico/metabolismo , Lisina/química , Lisina/metabolismo , Osteoblastos/metabolismo , Poliésteres/metabolismo , Polímeros/química , Porosidad
2.
Molecules ; 25(18)2020 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-32942756

RESUMEN

Efficient separation technologies are crucial to the environment and world economy. The challenge posed to scientists is how to engineer selectivity towards a targeted substrate, especially from multicomponent solutions. Polymer-supported reagents have gained a lot of attention in this context, as they eliminate a lot of inconveniences concerning widely used solvent extraction techniques. Nevertheless, the choice of an appropriate ligand for immobilization may be derived from the behavior of soluble compounds under solvent extraction conditions. Organophosphorus compounds play a significant role in separation science and technology. The features they possess, such as variable oxidation states, multivalence, asymmetry and metal-binding properties, highlight their status as a unique and versatile class of compounds, capable of selective separations proceeding through different mechanisms. This review provides a detailed survey of polymers containing phosphoric, phosphonic and phosphinic acid functionalities in the side chain and covers main advances in the preparation and application of these materials in separation science, including the most relevant synthesis routes (Arbuzov, Perkow, Mannich, Kabachnik-Fields reactions, etc.), as well as the main stages in the development of organophosphorus resins and the most important achievements in the field.


Asunto(s)
Resinas de Intercambio Iónico/química , Ácidos Fosfínicos/química , Ácidos Fosfóricos/química , Ácidos Fosforosos/química , Polímeros/química , Quelantes/química , Compuestos Organofosforados/química
3.
J Mol Recognit ; 31(3)2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-28322471

RESUMEN

For the last decades, molecular imprinting is developing intensively, especially in the case of the application of new imprinting techniques. In this work, for the first time, a Pickering emulsion polymerization was used to synthesize the S-naproxen-imprinted polymer spheres following a noncovalent protocol. To enhance the knowledge about imprinting process using mentioned technique, thorough analysis of the synthesis process was performed. Optimization of polymerization conditions included the selection of functional monomer, cross-linking agent, type of porogen, surfactant, and the choice of appropriate amount of the template and porogen. Prepared materials were characterized using scanning electron microscopy and nitrogen adsorption. To study the binding properties, the sorption studies, including adsorption isotherms and competitive binding, were performed. Investigation of the effect of the functional monomer on the selective recognition of S-naproxen showed that the interactions between the template molecule and 4-vinylpyridine resulted in the best recognizing ability. Moreover, the synthesis with application of ethylene glycol dimethacrylae as a cross-linker, toluene as a porogen, and Tween 20 as an additional emulsion stabilizer gave the most desired result. The optimal ratio of the porogen to monomers mixture was 0.1, due to the fact that the increase of the porogen volume resulted in the significant increase of nonspecific uptake. In addition, the tenfold molar excess of functional monomer relative to the template turned out to be optimal. Subsequent binding studies demonstrated that the material synthesized using optimized polymerization conditions consists of imprinted sites that are sensitive for the S-naproxen.


Asunto(s)
Impresión Molecular , Naproxeno/síntesis química , Polímeros/síntesis química , Adsorción , Humanos , Microscopía Electrónica de Rastreo , Naproxeno/química , Naproxeno/uso terapéutico , Nitrógeno , Polimerizacion , Polímeros/química , Piridinas/química
4.
J Sep Sci ; 35(15): 1953-8, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22865758

RESUMEN

Two imidazolium supported ionic liquid phases (SILPs) containing different anions, trifluoromethanesulphonate [CF(3)SO(3)(-)], and tetrafluoroborate [BF(4)(-)], were synthesized and evaluated as solid-phase extraction sorbents for extracting acidic pharmaceuticals from aqueous samples under strong anion-exchange conditions, which include an effective cleanup of the sample. The best SILP material [MI(+)][CF(3)SO(3)(-) ] was selected and successfully applied to the determination of acidic pharmaceuticals in different types of water samples (river water and effluent wastewater). The results were then compared to the previously synthesized SILP material based on [MI(+)][CF(3)COO(-)] and the commercially available Oasis MAX sorbent.


Asunto(s)
Resinas de Intercambio Aniónico/química , Preparaciones Farmacéuticas/análisis , Preparaciones Farmacéuticas/aislamiento & purificación , Extracción en Fase Sólida/métodos , Contaminantes Químicos del Agua/análisis , Adsorción , Boratos , Ácidos Bóricos/química , Líquidos Iónicos , Mesilatos/química , Polímeros/química , Ríos/química , Aguas del Alcantarillado/química , Extracción en Fase Sólida/instrumentación , Contaminantes Químicos del Agua/aislamiento & purificación
5.
Materials (Basel) ; 14(11)2021 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-34071203

RESUMEN

Novel, phosphorus-containing slow release fertilizer hydrogels (SRFHs) composed of interpenetrating polymer networks (IPNs) with very good swelling and mechanical properties have been obtained and characterized. It was found that introducing organophosphorus polymer based on a commercially available monomer, 2-methacryloyloxyethyl phosphate (MEP), as the IPN's first component network results in much better swelling properties than for a terpolymer with acrylic acid (AAc), 2-methacryloyloxyethyl phosphate (MEP) and bis[2-(methacryloyloxy)ethyl] phosphate (BMEP) when the same weight ratios of monomers are employed. The procedure described in this paper enables the introduction of much larger amounts of phosphorus into polymer structures without significant loss of water regain ability, which is crucial in the application of such materials in the agricultural field.

6.
PLoS One ; 7(8): e43354, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22916245

RESUMEN

Novel carbon materials have been prepared by the carbonization of acrylonitrile (AN)/divinylbenzene (DVB) suspension porous copolymers having nominal crosslinking degrees in the range of 30-70% and obtained in the presence of various amounts of porogens. The carbons were obtained by pre-oxidation of AN/DVB copolymers at 250-350°C in air followed by pyrolysis at 850°C in an N(2) atmosphere. Both processes were carried out in one furnace and the resulting material needed no further activation. Resulting materials were characterized by XPS and low temperature nitrogen adsorption/desorption. It was found that maximum pyrolysis yield was ca. 50% depending on the oxidation conditions but almost independent of the crosslinking degree of the polymers. Porous structure of the carbons was characterized for the presence of micropores and macropores, when obtained from highly crosslinked polymers or polymers oxidized at 350°C and meso- and macropores in all other cases. The latter pores are prevailing in the structure of carbons obtained from less porous AN/DVB resins. Specific surface area (BET) of polymer derived carbons can vary between 440 m(2)/g and 250 m(2)/g depending on the amount of porogen used in the synthesis of the AN/DVB polymeric precursors.


Asunto(s)
Acrilonitrilo/química , Carbono/química , Nanoestructuras/química , Polímeros/química , Polivinilos/química
7.
Talanta ; 80(1): 250-6, 2009 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-19782223

RESUMEN

This study reports a material that is based on the concept of ionic liquid analogue: a slightly crosslinked polymer-supported imidazolium trifluoroacetate salt (IL-CF(3)COO(-)) that favorably combines the properties of ionic liquids (ILs) and the advantages of a solid support. The ionic liquid-supported material was evaluated for the first time as a solid-phase extraction (SPE) sorbent for selectively and quantitatively extracting pharmaceuticals from aqueous samples. The novel IL-CF(3)COO(-) was evaluated under reversed-phase (RP), weak anion exchange (WAX), strong anion exchange (SAX) and strong cation exchange (SCX) SPE procedures, and we found that SAX conditions are the most suitable for investigating the behaviour of the IL-CF(3)COO(-) material. Under SAX conditions, the IL-CF(3)COO(-) material was capable of selectively and quantitatively extracting a group of acidic compounds from aqueous samples, while washing basic analytes that were also present in the sample. The SPE method using IL-CF(3)COO(-) material was used to analyse 1000 ml of different aqueous samples (ultrapure, tap and river) with complete recovery of the acidic compounds studied. Moreover, the method provided clean chromatogram and high recoveries when percolating complex real samples, such as 1000 ml of river water and 250 ml of effluent wastewater from a sewage treatment plant spiked at low levels with the analytes studied.


Asunto(s)
Imidazoles/química , Líquidos Iónicos/química , Extracción en Fase Sólida/métodos , Adsorción , Carbamazepina/análisis , Carbamazepina/química , Cromatografía Líquida de Alta Presión/instrumentación , Cromatografía Líquida de Alta Presión/métodos , Agua Dulce/análisis , Agua Dulce/química , Estructura Molecular , Ácido Nalidíxico/análisis , Ácido Nalidíxico/química , Nitrofenoles/análisis , Nitrofenoles/química , Ríos , Ácido Salicílico/análisis , Ácido Salicílico/química , Aguas del Alcantarillado/química , Extracción en Fase Sólida/instrumentación
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