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1.
J Chromatogr A ; 1623: 461192, 2020 Jul 19.
Article in English | MEDLINE | ID: mdl-32505285

ABSTRACT

An imidazolium ionic-liquid-modified phenolic resin (ILPR) was synthesized using 3-aminophenol as a functional monomer, glyoxylic acid as a green cross-linker, and polyethylene glycol 6000 as a porogen. The obtained ILPR showed better extraction of benzoylurea plant hormones thidiazuron and forchlorfenuron than the unmodified phenolic resin because the imidazolium IL provides more interaction modes with the analytes. ILPR, as a tailored adsorbent for solid-phase extraction, was coupled with high-performance liquid chromatography (ILPR‒SPE‒HPLC) for the simultaneous determination of thidiazuron and forchlorfenuron in cucumbers. Good linearity of the ILPR‒SPE‒HPLC method was obtained, ranging from 0.0100 to 5.00 µg g-1 with a correlation coefficient (r) ≥ 0.9999. The recoveries of spiked samples ranged from 91.4% to 100.7% with a relative standard deviation of ≤ 6.0%.


Subject(s)
Cucumis sativus/chemistry , Formaldehyde/chemistry , Imidazoles/chemistry , Ionic Liquids/chemistry , Phenols/chemistry , Phenylurea Compounds/isolation & purification , Polymers/chemistry , Pyridines/isolation & purification , Solid Phase Extraction/methods , Thiadiazoles/isolation & purification , Chromatography, High Pressure Liquid , Formaldehyde/chemical synthesis , Ionic Liquids/chemical synthesis , Kinetics , Phenols/chemical synthesis , Polymers/chemical synthesis , Reproducibility of Results
2.
Carbohydr Polym ; 239: 116217, 2020 Jul 01.
Article in English | MEDLINE | ID: mdl-32414428

ABSTRACT

Formaldehyde was detected in dialdehyde carboxymethyl cellulose (DCMC) tanning agent prepared through periodate oxidation of sodium carboxymethyl cellulose (CMC). Formaldehyde was then introduced into leather through DCMC tanning, which poses a potential risk to human health. The formation mechanism of formaldehyde in DCMC was investigated by composition analysis and intermediate identification of DCMC with different polymerization degrees and sugar unit structures. Formaldehyde was derived from the overoxidation of C-6 on the reducing glucose residue of CMC. Moreover, glucose was produced from the concomitant degradation of CMC during oxidation, and then oxidized to liberate formaldehyde. The low degradation degree and high degree of substitution of CMC reduced the possibility of the formation of reducing glucose residue and glucose during oxidation, thereby resulting in low formaldehyde content in DCMC and DCMC-tanned leather. These findings serve as a foundation for the minimization of formaldehyde in DCMC and the development of ecological tanning approach.


Subject(s)
Carboxymethylcellulose Sodium/chemistry , Cellulose/analogs & derivatives , Formaldehyde/chemical synthesis , Tanning , Carbohydrate Conformation , Cellulose/chemistry , Formaldehyde/chemistry , Oxidation-Reduction
3.
Macromol Rapid Commun ; 41(7): e1900654, 2020 Apr.
Article in English | MEDLINE | ID: mdl-32134544

ABSTRACT

The development of polymers with built-in sensors that provide readily perceptible optical warning signs of mechanical events has received considerable interest. A simple and versatile concept to bestow polymers with mechanochromic behavior is the incorporation of dye-filled microcapsules. Such capsules release their cargo when their shell is damaged, and the dye is subsequently activated through a chemical or physical change that causes a chromogenic response. Here, we report the preparation of fluorescent poly(urea-formaldehyde) microcapsules containing solutions of a solvatochromic cyanostilbene dye and their integration in different polymers. When objects made from such composites are damaged, the dye solution is released from the containers, diffuses into the matrix, and the solvent evaporates. As a result, the polarity around the dye molecules changes, and this leads to a change of the fluorescence color. Alternatively, the dye is blended into the polymer matrix, microcapsules are loaded with a solvent, and the release of the latter triggers the color change. Both mechanisms afford ratiometric signals because the capsules that remain intact or dye molecules that are not exposed to the solvent can be used as a built-in reference; therefore, a quantitative assessment of the damage inflicted on the material is a priori possible.


Subject(s)
Fluorescent Dyes/chemistry , Formaldehyde/chemistry , Polymers/chemistry , Urea/chemistry , Capsules/chemical synthesis , Capsules/chemistry , Fluorescent Dyes/chemical synthesis , Formaldehyde/chemical synthesis , Mechanical Phenomena , Molecular Structure , Particle Size , Polymers/chemical synthesis , Urea/chemical synthesis
4.
J Microencapsul ; 36(4): 410-419, 2019 Jun.
Article in English | MEDLINE | ID: mdl-31269832

ABSTRACT

Poly(urea-formaldehyde) (PUF) microcapsules filled with dicyclopentadiene (DCPD) were prepared by in situ polymerisation and the effect of synthesis parameters, such as pH of the solution and agitation rate, on microcapsules size and shell thickness was evaluated. Scanning electron microscopy (SEM) and Fourier transform infra-red spectroscopy (FTIR) were performed. Adjusted pH conditions (pH = 3.5) and agitation rate (1350 RPM) were found using a design of experiments (DOE). SEM results indicated that microcapsule size was directly affected by agitation rate, whereas shell thickness was mostly affected by pH. After obtaining adjusted synthesis conditions, microcapsules presenting mean size of 60 µm and mean shell thickness of 4 µm were embedded in an epoxy matrix for evaluating the self-healing effect. FTIR and SEM analyses in damaged samples suggested that a healing agent was delivered to the crack location.


Subject(s)
Capsules/chemical synthesis , Formaldehyde/chemical synthesis , Polymers/chemical synthesis , Capsules/chemistry , Chemistry Techniques, Synthetic , Drug Compounding , Formaldehyde/chemistry , Hydrogen-Ion Concentration , Indenes/administration & dosage , Particle Size , Polymerization , Polymers/chemistry
5.
Int J Biol Macromol ; 123: 1125-1131, 2019 Feb 15.
Article in English | MEDLINE | ID: mdl-30462986

ABSTRACT

In this study, porous magnetic resin grafted chitosan (R-g-Ch) beads were prepared for removal of 4-chlorophenol and phenol from aqueous solutions. The R-g-Ch beads were characterized by vibrating sample magnetometer, Fourier-transform infrared spectroscopy, scanning electron microscopy and thermogravimetry methods. The removal of the phenolic compounds was optimized by varying the experimental conditions. Results herein are well fitted to the pseudo-second order kinetic and Langmuir isotherm. The maximum adsorption capacity of phenol and 4-chlorophenol were found to be 188.6 and 99 mg/g, respectively. The thermodynamic studies suggested that the adsorption process was exothermic, irreversible and feasible within the range of 298-318 K.


Subject(s)
Chitosan/chemistry , Magnetics , Microspheres , Phenols/isolation & purification , Resins, Synthetic/chemistry , Adsorption , Chitosan/chemical synthesis , Chlorophenols/isolation & purification , Differential Thermal Analysis , Formaldehyde/chemical synthesis , Formaldehyde/chemistry , Hydrogen-Ion Concentration , Kinetics , Porosity , Resorcinols/chemical synthesis , Resorcinols/chemistry , Solutions , Temperature , Thermogravimetry , Time Factors , Triazines/chemical synthesis , Triazines/chemistry
6.
Macromol Rapid Commun ; 40(17): e1800702, 2019 Sep.
Article in English | MEDLINE | ID: mdl-30556227

ABSTRACT

In this study, an innovative, facile, and low-cost method is developed to prepare phenolic resin (PR) containing boron and silicon (BSiPR). BSiPR is synthesized by a solvent-free, one-pot method using boric acid as the coupling agent instead of silane, and methyltriethoxysilane as the silicon source. The results show that boron and silicon elements are introduced into PR via BOC and BOSi structures. The char yield of the resulting resin at 800 °C is improved to 76%. The reasons for higher char yield are investigated. The formation of BOC can reduce the content of phenolic hydroxyl, which helps to decrease the weight loss. B2 O3 is also formed at 400 °C, and it can prevent the release of carbon oxides. Moreover, thermally stable BOSi and SiO structures remain stable during the pyrolysis. In addition, the mechanical and ablative properties of fiber-reinforced composites are also enhanced.


Subject(s)
Boric Acids/chemistry , Boron/chemistry , Charcoal/chemistry , Formaldehyde/chemical synthesis , Phenols/chemical synthesis , Polymers/chemical synthesis , Silicon/chemistry , Formaldehyde/chemistry , Materials Testing , Phenols/chemistry , Polymers/chemistry , Surface Properties
7.
PLoS One ; 13(5): e0195069, 2018.
Article in English | MEDLINE | ID: mdl-29851953

ABSTRACT

The physico-chemical and application properties of phenol-formaldehyde resins used in the production of laminated plastics depend on such factors as: type and amount of catalyst, formaldehyde-to-phenol mole ratio, temperature and time of the synthesis process. The special impact on the reaction mechanism and kinetics, e.g. on the formation of mono-, di- and trihydroxymethyl derivatives of phenol (PhOH) is a consequence of the type and amount of the catalyst. This paper presents the results of optimisation research of resol resin synthesis catalysed by trimethylamine (TEA) carried out according to 32 experimental design. The aim of the research was to determine the synthesis conditions under which it is possible to achieve products with reduced content of unconverted formaldehyde (CH2O), phenol and its hydroxymetyl derivatives, while maintaining the required physico-chemical properties. The process employing selected polyamines as well as TEA together with polyamine co-catalysts i.e. diethylenetriamine (DETA) and triethylenetetraamine (TETA) was also studied. The results were compared with those of the resins which were synthesised with the use of classic catalysts-ammonia (NH3) and triethylamine for which the content of CH2O, PhOH and its hydroxymethyl derivatives was respectively: NH3-5.13% and 46.27%, TEA-0.33% and 52.41%. In the case DETA was added, the content of phenol and its hydroxymethyl derivatives could be reduced by 52.49% in relation to the resin obtained with the use of TEA and by 46.19% in relation to the resin obtained with the use of ammonia. The formaldehyde content was reduced by 78.79% and 98.64%, respectively. When TETA was added as a co-catalyst, the content of phenol and its derivatives was reduced by 48.04% versus triethylamine-catalysed resin and by 41.15% versus ammonia-catalysed material. The reduction in formaldehyde content reached 84.85% and 99.03%, respectively. The results of kinetic study were also presented, the prediction accuracy of the proposed kinetic model is more than 98% for all the catalysts in the state variable space. Polyamine co-catalysts gave much higher rate constants (0.50 and 0.45 for TETA and DETA, respectively).


Subject(s)
Formaldehyde/chemistry , Models, Statistical , Phenols/chemistry , Polyamines/chemistry , Polymers/chemistry , Catalysis , Formaldehyde/chemical synthesis , Kinetics , Phenols/chemical synthesis , Polymers/chemical synthesis , Temperature
8.
Chemistry ; 23(55): 13734-13741, 2017 Oct 04.
Article in English | MEDLINE | ID: mdl-28699298

ABSTRACT

Highly ordered mesoporous resol-type phenolic resin and the corresponding mesoporous carbon materials were synthesized by using poly(ethylene oxide-b-caprolactone) (PEO-b-PCL) diblock copolymer as a soft template. The self-assembled mesoporous phenolic resin was found to form only in a specific resol concentration range of 40-70 wt % due to an intriguing balance of hydrogen-bonding interactions in the resol/PEO-b-PCL mixtures. Furthermore, morphological transitions of the mesostructures from disordered to gyroid to cylindrical and finally to disordered micelle structure were observed with increasing resol concentration. By calcination under nitrogen atmosphere at 800 °C, the bicontinuous mesostructured gyroid phenolic resin could be converted to mesoporous carbon with large pore size without collapse of the original mesostructure. Furthermore, post-treatment of the mesoporous gyroid phenolic resin with melamine gave rise to N-doped mesoporous carbon with unique electronic properties for realizing high CO2 adsorption capacity (6.72 mmol g-1 at 0 °C).


Subject(s)
Carbon/chemistry , Formaldehyde/chemistry , Nitrogen/chemistry , Phenols/chemistry , Polyesters/chemistry , Polymers/chemistry , Adsorption , Calorimetry, Differential Scanning , Carbon Dioxide/chemistry , Formaldehyde/chemical synthesis , Microscopy, Electron, Transmission , Phenols/chemical synthesis , Polyesters/chemical synthesis , Polymers/chemical synthesis , Porosity , Scattering, Small Angle , Triazines/chemistry , X-Ray Diffraction
9.
ChemSusChem ; 9(20): 2905-2907, 2016 Oct 20.
Article in English | MEDLINE | ID: mdl-27634670

ABSTRACT

Over 30 megatons of formaldehyde are required per year and industrially produced through three high-temperature gas-phase processes: i) natural gas reforming to syngas, ii) methanol synthesis, and iii) partial oxidation to formaldehyde with limited selectivity. In vast contrast to these energy-intensive oxidative and dehydrogenative methods, a reductive "top-down" methodology using CO2 and CO as carbon source would be desirable and is not very well present in the literature for more than 100 years. The key to success is the reaction performance in liquid solution in water or methanol at low temperature.


Subject(s)
Cold Temperature , Formaldehyde/chemical synthesis , Carbon Monoxide/chemistry , Solutions
10.
Org Biomol Chem ; 13(45): 11052-71, 2015 Dec 07.
Article in English | MEDLINE | ID: mdl-26394794

ABSTRACT

A solution phase synthesis of peptide nucleic acid monomers and dimers was developed by using microwave-promoted Ugi multicomponent reactions. A mixture of a functionalized amine, a carboxymethyl nucleobase, paraformaldehyde and an isocyanide as building blocks generates PNA monomers which are then partially deprotected and used in a second Ugi 4CC reaction, leading to PNA dimers. Conformational rotamers were identified by using NMR and MD simulations.


Subject(s)
Peptide Nucleic Acids/chemical synthesis , Cyanides/chemical synthesis , Cyanides/chemistry , Dimerization , Formaldehyde/chemical synthesis , Formaldehyde/chemistry , Magnetic Resonance Spectroscopy , Microwaves , Molecular Dynamics Simulation , Peptide Nucleic Acids/chemistry , Polymers/chemical synthesis , Polymers/chemistry
12.
J Am Chem Soc ; 135(28): 10206-9, 2013 Jul 17.
Article in English | MEDLINE | ID: mdl-23819680

ABSTRACT

It is well established that adding methanol to water could significantly enhance H2 production by TiO2. Recently, we have found that methanol can be photocatalytically dissociated on TiO2(110) at 400 nm via a stepwise mechanism. However, how molecular hydrogen can be formed from the photocatalyzed methanol/TiO2(110) surface is still not clear. In this work, we have investigated deuterium formation from photocatalysis of the fully deuterated methanol (CD3OD) on TiO2(110) at 400 nm using a temperature programmed desorption (TPD) technique. Photocatalytic dissociation products formaldehyde (CD2O) and D-atoms on BBO sites (via D2O TPD product) have been detected. In addition to D2O formation by heating the photocatalyzed methanol/TiO2(110) surface, we have also observed D2 product formation. D2 is clearly formed via thermal recombination of the D-atoms on the BBO sites from photocatalysis of methanol. Experimental results indicate that D2O formation is more important than D2 formation and that D2 formation is clearly affected by the D2O formation process.


Subject(s)
Formaldehyde/chemical synthesis , Hydrogen/chemistry , Methanol/chemistry , Photochemical Processes , Titanium/chemistry , Catalysis , Formaldehyde/chemistry , Surface Properties
13.
J Chem Phys ; 138(18): 184701, 2013 May 14.
Article in English | MEDLINE | ID: mdl-23676058

ABSTRACT

Methanol is the future and clean fuel, and its chemistry on metal surfaces has received much attention. In this paper we explore methanol dissociation on the clean and O or OH covered PdZn(111) that mimics Pd∕ZnO catalyst studied as a promising catalyst for methanol steam reforming, using density functional theory at PW91 level and slab model. Our study demonstrates that unlike the situation on Pd (111), methanol preferentially undergoes the O-H bond scission on the PdZn (111). The presence of O and OH species hinders the C-H bond dissociation, but significantly reduces the O-H bond-breaking barrier. The present results indicate that in the course of methanol steam reforming, methanol first loses the hydrogen atom of the hydroxyl group, forming methoxy. This step is greatly enhanced when there are O and∕or OH species (i.e., after water dissociation happens). Analyses reveal that CH2O is formed mainly from CH3O, not from CH2OH.


Subject(s)
Hydroxides/chemistry , Methanol/chemistry , Oxygen/chemistry , Palladium/chemistry , Quantum Theory , Zinc/chemistry , Adsorption , Formaldehyde/chemical synthesis , Formaldehyde/chemistry , Surface Properties
14.
J Am Chem Soc ; 135(22): 8113-6, 2013 Jun 05.
Article in English | MEDLINE | ID: mdl-23688031

ABSTRACT

We disclose the first catalytic activation of carbohydrates as formaldehyde equivalents to generate acyl anions as one-carbon nucleophilic units for a Stetter reaction. The activation involves N-heterocyclic carbene (NHC)-catalyzed C-C bond cleavage of carbohydrates via a retro-benzoin-type process to generate the acyl anion intermediates. This Stetter reaction constitutes the first success in generating formal formaldehyde-derived acyl anions as one-carbon nucleophiles for non-self-benzoin processes. The renewable nature of carbohydrates, accessible from biomass, further highlights the practical potential of this fundamentally interesting catalytic activation.


Subject(s)
Carbohydrates/chemistry , Formaldehyde/chemical synthesis , Heterocyclic Compounds/chemistry , Ketones/chemistry , Methane/analogs & derivatives , Catalysis , Formaldehyde/chemistry , Methane/chemistry , Molecular Structure
15.
Phys Chem Chem Phys ; 15(13): 4699-706, 2013 Apr 07.
Article in English | MEDLINE | ID: mdl-23422959

ABSTRACT

Reaction of CO with H2 on neutral FemSn clusters in a fast flow reactor is investigated both experimentally and theoretically. Single photon ionization at 118 nm is used to detect neutral cluster distributions through time of flight mass spectrometry. FemSn clusters are generated through laser ablation of a mixed iron-sulfur target in the presence of a pure helium carrier gas. A strong size dependent reactivity of (FeS)m clusters toward CO is characterized. The reaction FeS + CO → Fe + OCS is found for the FeS cluster, and the association product Fe2S2CO is observed for the Fe2S2 cluster. Products Fe2S2(13)COH2 and Fe2S2(13)COH4 are identified for reactions of (13)CO and H2 on Fe2S2 clusters: this suggests that the Fe2S2 cluster has a high catalytic activity for hydrogenation reactions of CO to form formaldehyde and methanol. Density functional theory (DFT) calculations are performed to explore the potential energy surfaces for the two reactions: Fe2S2 + CO + 2H2 → Fe2S2 + CH3OH; and Fe2S2 + CO + H2 → Fe2S2 + CH2O. A barrierless, thermodynamically favorable pathway is obtained for both catalytic processes. Catalytic cycles for formaldehyde and methanol formation from CO and H2 on a Fe2S2 cluster are proposed based on our experimental and theoretical investigations. The various reaction mechanisms explored by DFT are in good agreement with the experimental results. Condensed phase iron sulfide, which contains exposed Fe2S2 units on its surface, is suggested to be a good catalyst for low temperature formaldehyde/methanol synthesis.


Subject(s)
Carbon Monoxide/chemistry , Formaldehyde/chemical synthesis , Hydrogen/chemistry , Iron-Sulfur Proteins/chemistry , Methanol/chemical synthesis , Catalysis , Formaldehyde/chemistry , Gases/chemistry , Methanol/chemistry , Quantum Theory , Thermodynamics
16.
J Enzyme Inhib Med Chem ; 28(2): 337-42, 2013 Apr.
Article in English | MEDLINE | ID: mdl-22994608

ABSTRACT

Mannich bases 2a-f derived from 3,4-dimethylphenol (1), formaldehyde and different amines are prepared and subjected to spectral (IR, (1)H and (13)C NMR) and elemental analyses. The inhibition of two human carbonic anhydrase (hCA, EC 4.2.1.1) isozymes I and II, with 1 and synthesized Mannich bases 2a-f and acetazolamide (AAZ) as a control compound was investigated in vitro by using the hydratase and esterase assays. In relation to hydratase and esterase activities of the half maximal inhibitory concentration (IC(50)) and the inhibition equilibrium constants (K(i))values were determined. Only two compounds (2a and 2e)exhibit weak hCA II inhibitory effects on esterase activity. IC(50) and Ki values for 2a and 2e with respect to esterase activity of hCA II are0.88 × 10(3) and 6.3-7.6 µM and 0.44 × 10(3) and 19.0-96.4 µM,respectively. On the contrary, compounds 2b and 2d might be used as CA activators due to increasing esterase activity of hCA I and hCA II isozymes.


Subject(s)
Amines/pharmacology , Carbonic Anhydrase Inhibitors/pharmacology , Carbonic Anhydrases/metabolism , Formaldehyde/pharmacology , Xylenes/pharmacology , Amines/chemical synthesis , Amines/chemistry , Carbonic Anhydrase Inhibitors/chemical synthesis , Carbonic Anhydrase Inhibitors/chemistry , Carbonic Anhydrases/isolation & purification , Dose-Response Relationship, Drug , Erythrocytes/enzymology , Formaldehyde/chemical synthesis , Formaldehyde/chemistry , Humans , Molecular Structure , Protein Isoforms/antagonists & inhibitors , Protein Isoforms/isolation & purification , Protein Isoforms/metabolism , Structure-Activity Relationship , Xylenes/chemical synthesis , Xylenes/chemistry
17.
Article in English | MEDLINE | ID: mdl-22683552

ABSTRACT

Phenylurea-formaldehyde polymer (PUF) was synthesized via polycondensation of phenylurea and formaldehyde in basic medium, its polymer-metal complexes [PUF-M(II)] were prepared with Mn(II), Co(II), Ni(II), Cu(II), and Zn(II) ions. PUF and PUF-M(II) were characterized with magnetic moment measurements, elemental and spectral (UV-visible, FTIR, 1H-NMR, 13C-NMR and ESR) analysis. The thermal behaviors of all the synthesized polymers were carried out using thermogravimetric analysis (TGA) and differential thermal analysis (DTA). The thermal data revealed that all of the PUF-M(II) showed higher thermal stabilities than the PUF and also ascribed that the PUF-Cu(II) showed better thermal stability than the other PUF-M(II). The kinetic parameters such as activation energy, pre-exponential factor etc., were evaluated for these polymer metal complexes using Coats-Redfern equation. In addition, the antimicrobial activity of the synthesized polymers was tested against several microorganisms using agar well diffusion methods. Among all of the PUF-M(II), the antimicrobial activity of the PUF-Cu(II) showed the highest zone of inhibition because of its higher stability constant and may be used in biomedical applications.


Subject(s)
Anti-Infective Agents/chemical synthesis , Anti-Infective Agents/pharmacology , Coordination Complexes/chemical synthesis , Formaldehyde/chemical synthesis , Formaldehyde/pharmacology , Manganese/pharmacology , Nylons/chemical synthesis , Nylons/pharmacology , Phenylurea Compounds/chemical synthesis , Phenylurea Compounds/pharmacology , Polymers/chemical synthesis , Anti-Bacterial Agents/chemical synthesis , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Anti-Infective Agents/chemistry , Antifungal Agents/chemical synthesis , Antifungal Agents/chemistry , Antifungal Agents/pharmacology , Bacteria/drug effects , Coordination Complexes/chemistry , Coordination Complexes/pharmacology , Differential Thermal Analysis , Electron Spin Resonance Spectroscopy , Formaldehyde/chemistry , Fungi/drug effects , Kinetics , Ligands , Magnetic Phenomena , Magnetic Resonance Spectroscopy , Manganese/chemistry , Microbial Sensitivity Tests , Nylons/chemistry , Phenylurea Compounds/chemistry , Polymers/chemistry , Polymers/pharmacology , Spectroscopy, Fourier Transform Infrared , Thermogravimetry
18.
Chemistry ; 18(30): 9294-9, 2012 Jul 23.
Article in English | MEDLINE | ID: mdl-22744779

ABSTRACT

Multifunctional Ag@Au@ phenol formaldehyde resin (PFR) particles loaded with folic acids (FA) have been designed for killing tumor cells through photothermy conversion under the irradiation of near-infrared (NIR) light. Possessing the virtue of good fluorescence, low toxicity, and good targeting, the nanocomposite consists of an Ag core, an Au layer, a PFR shell, and folic acids on the PFR shell. The Ag@PFR core-shell structure can be prepared with a simple hydrothermal method after preheating. We then filled the PFR shell with a layer of Au by heating and modified the shell with polyelectrolyte to change its surface charge state. To capture tumor cells actively, FA molecules were attached onto the surface of the Ag@Au@PFR particles in the presence of 1-ethyl-3-(3-dimethly aminopropyl) carbodiimide (EDAC) and N-hydroxysuccinimide (NHS). Owing to the excellent property of Au NPs and Ag NPs as photothermal conversion agents, the Ag@Au@ PFR@FA particles can be utilized to kill tumor cells when exposed to NIR light.


Subject(s)
Folic Acid/chemistry , Formaldehyde/chemistry , Formaldehyde/chemical synthesis , Metal Nanoparticles/chemistry , Metal Nanoparticles/therapeutic use , Phenol/chemistry , Phenol/chemical synthesis , Phenols/chemistry , Phenols/chemical synthesis , Polymers/chemistry , Polymers/chemical synthesis , Silver/chemistry , Silver/therapeutic use , Photometry , Phototherapy , Spectroscopy, Near-Infrared , Succinimides/chemistry
19.
Org Biomol Chem ; 10(16): 3164-7, 2012 Apr 28.
Article in English | MEDLINE | ID: mdl-22349519

ABSTRACT

A mild and efficient synthesis of 1-aryl-1-fluoroethenes from benzothiazolyl (aryl)fluoromethyl sulfones and paraformaldehyde, under DBU- or Cs(2)CO(3)-mediated conditions at room temperature, is described. A comparable diethyl fluoro(naphthalen-2-yl)methylphosphonate reagent does not react with paraformaldehyde under these mild conditions. The utility of the methodology for synthesis of terminal α-fluoroalkenes bearing electron-withdrawing functionalities is also shown.


Subject(s)
Chemistry Techniques, Synthetic/methods , Ethylenes/chemical synthesis , Fluorine/chemistry , Chemistry Techniques, Synthetic/economics , Ethylenes/chemistry , Formaldehyde/chemical synthesis , Formaldehyde/chemistry , Halogenation , Polymers/chemical synthesis , Polymers/chemistry , Sulfones/chemical synthesis , Sulfones/chemistry
20.
Chemistry ; 18(4): 1154-60, 2012 Jan 23.
Article in English | MEDLINE | ID: mdl-22190410

ABSTRACT

A magnetic, sensitive, and selective fluorescence resonance energy transfer (FRET) probe for detection of thiols in living cells was designed and prepared. The FRET probe consists of an Fe(3)O(4) core, a green-luminescent phenol formaldehyde resin (PFR) shell, and Au nanoparticles (NPs) as FRET quenching agent on the surface of the PFR shell. The Fe(3)O(4) NPs were used as the core and coated with green-luminescent PFR nanoshells by a simple hydrothermal approach. Au NPs were then loaded onto the surface of the PFR shell by electric charge absorption between Fe(3)O(4)@PFR and Au NPs after modifying the Fe(3)O(4)@PFR nanocomposites with polymers to alter the charge of the PFR shell. Thus, a FRET probe can be designed on the basis of the quenching effect of Au NPs on the fluorescence of Fe(3)O(4)@PFR nanocomposites. This magnetic and sensitive FRET probe was used to detect three kinds of primary biological thiols (glutathione, homocysteine, and cysteine) in cells. Such a multifunctional fluorescent probe shows advantages of strong magnetism for sample separation, sensitive response for sample detection, and low toxicity without injury to cellular components.


Subject(s)
Chemistry Techniques, Analytical/methods , Ferric Compounds/chemistry , Formaldehyde/chemistry , Gold/chemistry , Magnetics , Metal Nanoparticles/chemistry , Phenols/chemistry , Polymers/chemistry , Sulfhydryl Compounds/analysis , Cells/chemistry , Ferric Compounds/chemical synthesis , Fluorescence Resonance Energy Transfer , Fluorescent Dyes/chemistry , Formaldehyde/chemical synthesis , HeLa Cells , Humans , Limit of Detection , Microscopy, Electron, Scanning , Phenols/chemical synthesis , Polymers/chemical synthesis
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