Showing papers on "Thioglycolic acid published in 2016"
TL;DR: Graphene oxide was modified with third-generation poly(amidoamine) (PAMAM) to obtain dendrimer-grafted GO (DGO) with high content of functional groups.
Abstract: Graphene oxide was modified with third-generation poly(amidoamine) (PAMAM) to obtain dendrimer-grafted GO (DGO) with high content of functional groups. DGO's amine groups were conjugated with S-(thiobenzoyl)thioglycolic acid as proved by XPS and poly(acrylic acid) was grafted onto surface via RAFT polymerization (DGO@PAA). FT-IR results approved the synthesis of samples whereas TGA revealed 40.3% grafting of PAA. XRD patterns showed that with further modification, d-spacing increased. According to Raman spectra, modification resulted in more disordered structure whereas DGO@PAA showed a high value of ID/IG. Morphological studies were performed by SEM and TEM that showed a polymeric layer covered the surface of nanosheets.
48 citations
TL;DR: In this article, a facile photoelectrochemical sensor for the determination of hydrogen sulfide (H 2 S) is developed, where the surface of TiO 2 nanotubes was modified by a layer of thioglycolic acid (TGA) to introduce thiol groups which can adsorb and immobilize Cd ions.
42 citations
TL;DR: A rapid, simple and inexpensive spectrofluorimetric sensor for determination of doxycycline based on its interaction with thioglycolic acid-capped cadmium telluride quantum dots (TGA/CdTe QDs) has been developed and revealed that doxy cycline could quench the fluorescence of TGA/ CdTeQDs via electron transfer from the QDs through a dynamic quenching mechanism.
35 citations
TL;DR: The biocompatibility, peculiar morphology and thiol moieties of TCS as stent coating material appear application potential for vascular stent, which favored HUVECs adhesion and proliferation.
31 citations
TL;DR: In this paper, different Schiff's base templates have been obtained to mediate phase selective synthesis of α- or γ-Fe2O3 from the same temperature condition, and the inherent phase transformation tendency (γ-Fe 2 O3 to α-Fe O3) is found to be inhibited.
Abstract: Different Schiff's base (SB) templates have been obtained to mediate phase selective synthesis of α- or γ-Fe2O3 from the same temperature condition. The inherent phase transformation tendency (γ-Fe2O3 to α-Fe2O3) is found to be inhibited. Again, the phase selective evolution emerges out of the binding modes of SBs which has been illustrated here. The nature of SBs governs the shape and size distribution of Fe2O3 NPs. As both the phases are magenetically active, easy magnetic separation of them widens their applicability in catalysis. Magnetically active both α- and γ-Fe2O3 mimic interesting peroxidase like activity by oxidising colourless 3,3′,5,5′-tetramethylbenzidine (TMB) to blue coloured oxidised product (Ox-TMB) in aqueous H2O2. These results prompted us to improvise further to detect thioglycolic acid (TGA) at a micromolar level which provides commercial applicability.
31 citations
TL;DR: In this article, the authors synthesized and studied a support of NiMo using ammonium heptamolybdate and nickel nitrate and compared the results with TGA.
Abstract: Nb modified mesoporous SBA-15 and HMS materials were synthesized and studied as a support of NiMo. Calcined co-impregnated NiMo catalysts were prepared using ammonium heptamolybdate and nickel nitrate. Moreover, NiMo catalysts prepared in this manner were treated with thioglycolic acid (TGA). For comparison, NiMo catalysts were prepared by a simultaneous impregnation of the supports with Ni, Mo precursors and TGA. The TGA:Mo molar ratio was 4.0. The supports and NiMo catalysts were characterized by N 2 physisorption, small- and wide-angle XRD, TPD-NH 3 , SEM, UV–vis DRS, FTIR and XPS. Catalyst activity was examined in hydrodesulfurization (HDS) reactions of 1-benzothiophene and thiophene at 350 °C. It was found that simultaneous impregnation by Ni, Mo and TGA led to higher HDS activities than the sequential treatment of the calcined NiMo catalysts by TGA.
31 citations
TL;DR: The developed method was successfully applied to the determination of Cu(2+) in water samples and good recoveries of 93-104%, with a relative standard deviation of < 6% demonstrated that the developed simple method was accurate and reliable.
Abstract: CdTe quantum dots (QDs) capped with different stabilizers, i.e. thioglycolic acid (TGA), 3-mercaptopropionic acid (MPA) and glutathione (GSH) were investigated as fluorescent probes for the determination of Cu(2+). The stabilizer was shown to play an important role in both the sensitivity and selectivity for the determination of Cu(2+). TGA-capped CdTe QDs showed the highest sensitivity, followed by the MPA and GSH-capped CdTe QDs, respectively. The TGA- and MPA-capped CdTe QDs were not selective for Cu(2+) that was affected by Ag(+). The GSH-capped CdTe QDs were insensitive to Ag(+) and were used to determine Cu(2+) in water samples. Under optimal conditions, quenching of the fluorescence intensity (F0/F) increased linearly with the concentration of Cu(2+) over a range of 0.10-4.0 µg/mL and the detection limit was 0.06 µg/mL. The developed method was successfully applied to the determination of Cu(2+) in water samples. Good recoveries of 93-104%, with a relative standard deviation of < 6% demonstrated that the developed simple method was accurate and reliable. The quenching mechanisms were also described.
31 citations
TL;DR: In this article, the preparation of a nanocomposite consisting of soluble eggshell membrane protein (SEP) doped with reduced graphene oxide (rGO) as a sorbent for the preconcentration of mercury(II) by solid phase extraction (SPE).
Abstract: This article describes the preparation of a nanocomposite consisting of soluble eggshell membrane protein (SEP) doped with reduced graphene oxide (rGO) as a sorbent for the preconcentration of mercury(II) by solid phase extraction (SPE). Incorporation of rGO was accomplished by dissolving the eggshell membrane in a mixture of thioglycolic acid and acetic acid, adding graphene oxide, and sonicating the solution. The brown GO-SEP nanocomposite was then chemically reduced to black rGO-SEP using hydrazine as the reducing agent. The nanocomposite was found to be an efficient nanosorbent for SPE of mercury(II). Following desorption of Hg(II) ions from the sorbent with thiourea, Hg(II) was quantified by anodic stripping voltammetry. Under optimized extraction and electroanalytical conditions, the method has a wide analytical range that is linear in the 0.5–80 ng mL−1 Hg(II) concentration range. The lower detection limit is 0.14 mg mL−1, the enrichment factor is 50, and the sorption capacity is as high as 77 mg g−1.
27 citations
TL;DR: The reaction of aromatic aldehydes with Meldrum's acid and malononitrile dimer in the presence of triethylamine led to the formation of (4-aryl-3-cyano-6-oxopiperidin-2-ylidene)malononitriles.
Abstract: The reaction of aromatic aldehydes with Meldrum's acid and malononitrile dimer in the presence of triethylamine led to the formation of (4-aryl-3-cyano-6-oxo-1,4,5,6-tetrahydropyridin-2-yl)malononitrile triethylammonium salts, which were converted upon acidification to (4-aryl-3-cyano-6-oxopiperidin-2-ylidene)malononitriles. The reaction of these compounds with thioglycolic acid anilide was observed to produce derivatives of 1,6-naphthyridine or thieno[2,3-h][1,6]naphthyridine, depending on the conditions. Structures of (3-cyano-6-oxo-4-phenylpiperidin-2-ylidene)malononitrile and its triethylammonium salt were studied by X-ray structural analysis.
26 citations
TL;DR: In this article, water-soluble thioglycolic acid-capped ZnS quantum dots were synthesized by chemical precipitation method using x-ray diffraction and transmission electron microscopy.
Abstract: In this research, water-soluble thioglycolic acid-capped ZnS quantum dots (QDs) are synthesized by the chemical precipitation method. The prepared QDs are characterized using x-ray diffraction and transmission electron microscopy. Results revealed that ZnS QDs have a 2.73 nm crystallite size, cubic zinc blende structure, and spherical morphology with a diameter less than 10 nm. Photoluminescence (PL) spectroscopy is performed to determine the presence of low concentrations of starch. Four emission peaks are observed at 348 nm, 387 nm, 422 nm, and 486 nm and their intensities are quenched by increasing concentration of starch. PL intensity variations in the studied concentrations range (0–100 ppm) are best described by a Michaelis–Menten model. The Michaelis constant (K
m) for immobilized α-amylase in this system is about 101.07 ppm. This implies a great tendency for the enzyme to hydrolyze the starch as substrate. Finally, the limit of detection is found to be about 6.64 ppm.
23 citations
TL;DR: In this paper, a new approach was proposed to synthesize the CdSe@Ag 2 Se core-shell fluorescent quantum dots as a novel and sensitive electrochemical sensor for methyldopa.
Abstract: In this work, we offer a new approach to synthesize the CdSe@Ag 2 Se core–shell fluorescent quantum dots as a novel and sensitive electrochemical sensor for methyldopa by casting of an aliquot of thioglycolic acid capped CdSe@Ag 2 Se on a glassy carbon electrode surface. Characterizing the CdSe@Ag 2 Se was investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD), FT-IR spectroscopy, photoluminescence spectroscopy, UV–vis and cyclic voltammetry techniques. Under the optimal experimental conditions (pH = 2), the current response of the electrochemical sensor obtained with differential pulse voltammetry was increased linearly with methyldopa concentrations in the wide range from 0.09 to 60 μmol L −1 , with the detection limit of 0.04 μmol L −1 . The proposed sensor was successfully used for analysis of methyldopa in biological and pharmaceutical samples without any interference from uric acid and ascorbic acid due to its high sensitivity and selectivity, good repeatability and reproducibility, and low detection limit.
TL;DR: In the present research, water soluble thioglycolic acid-capped CdS quantum dots (QDs) were synthesized by chemical precipitation method and the characteristics of prepared quantum dots were determined using X-Ray Diffraction and Transmission Electron Microscopy.
Abstract: In the present research, water soluble thioglycolic acid-capped CdS quantum dots (QDs) were synthesized by chemical precipitation method. The characteristics of prepared quantum dots were determined using X-Ray Diffraction (XRD) and Transmission Electron Microscopy (TEM). The obtained results revealed that CdS QDs have 5.60 nm crystallite size, hexagonal wurtzite structure and spherical morphology with less than 10 nm diameter. The photoluminescence (PL) spectroscopy was performed in order to study the effect of the presence of starch solutions. Blue emission peaks were positioned at 488 nm and its intensity quenched by increasing the concentration of starch solutions. The result of PL quenches in range of studied concentrations (0-100 ppm) was best described by Michaelis-Menten model. The amount of Michaelis constant (Km) for immobilized α-amylase in this system was about 68.08 ppm which showed a great tendency of enzyme to hydrolyze the starch as substrate. Finally, the limit of detection (LOD) was found to be about 2.24 ppm.
TL;DR: Hair keratin peptides were electrospun with PVA and subjected to morphological, mechanical, thermal and biological characterizations to help in understanding the extraction-structure-function aspect of the hydrolysates stressing the role of extraction methods on the choice of application.
Abstract: Drawing inspiration from the field of designer self-assembling materials, this work is aimed to focus on the self-assembling nature of extracted peptides. Hair keratin, a proteinacious reject in tanning industry has been chosen since they have been extracted and used for wide range of applications. Keratin source was subjected to five hydrolysis treatments (viz., sulphitolysis, β-mercaptoethanol, ionic liquid, thioglycolic acid and alkali) and assayed for functional groups. This was followed by the prediction of secondary structure using circular dichroism, determining the microstructural level to which the extracted peptide has self-assembled. Sulphitolysis and thioglycolic acid based hydrolysates exist in monomeric conformation, whereas β-mercaptoethanol based hydrolysate exhibited dimeric conformation. The subsequent part of the study is to incorporate these peptides into the nanofibers to study the structural implication of keratin peptides on its characteristics. Accordingly, the peptides were electrospun with PVA and subjected to morphological, mechanical, thermal and biological characterizations. Monomeric nanofiber mat has high tensile strength of around 5.5 MPa and offered lower mass transport resistance, whereas dimeric mat has high Tm of around 290 °C and was more biocompatible. These results help in understanding the extraction-structure-function aspect of the hydrolysates stressing the role of extraction methods on the choice of application.
TL;DR: An energy-efficient eco-friendly methodology for the synthesis of a series of pharmacologically important spiro[indoline-3,2′-thiazolidinones] has been developed by the reaction of primary amines with various isatin derivatives and thioglycolic acid in the presence of p-dodecylbenzenesulfonic acid (DBSA) as an efficient Bronsted acid surfactant combined catalyst in aqueous medium at 25°C as mentioned in this paper.
TL;DR: In this paper, different heterocyclic compounds were prepared starting from 2-hydroxy benzohydrazide; the structures of all newly isolated compounds were confirmed using 1H NMR, IR spectra, and elemental analyses.
10 Oct 2016
TL;DR: A facile and cadmium-free approach to prepare water-soluble fluorescent ZnSe@ZnS core-shell quantum dots (QDs), using thioglycolic acid (TGA) ligand as stabilizer and thiourea as a sulfur source, was reported in this paper.
Abstract: Herein we report a facile and cadmium-free approach to prepare water-soluble fluorescent ZnSe@ZnS core–shell quantum dots (QDs), using thioglycolic acid (TGA) ligand as a stabilizer and thiourea as a sulfur source. The optical properties and morphology of the obtained core–shell QDs were characterized by UV–vis and fluorescence spectroscopy, transmission electron microscopy (TEM), energy-dispersive x-ray analysis (EDX), x-ray diffraction (XRD), electrophoresis and dynamic light scattering (DLS) techniques. TEM analysis, and electrophoresis data showed that ZnSe core had an average size of 3.60 ± 0.12 nm and zeta potential of −38 mV; and for ZnSe@ZnS QDs, the mean size was 4.80 ± 0.20 nm and zeta potential was −45 mV. Compared to the core ZnSe QDs, the quantum yield of these core–shell structures was higher (13% versus 32%). These were interacted with five common bioanalytes such as, ascorbic acid, citric acid, oxalic acid, glucose and cholesterol which revealed fluorescence quenching due to concentration dependent binding of analytes to the core only, and core–shell QDs. The binding pattern followed the sequence: cholesterol < glucose < ascorbic acid < oxalic acid < citric acid for ZnSe, and cholesterol < glucose < oxalic acid < ascorbic acid < citric acid for core–shell QDs. Thus, enhanced binding was noticed for the analyte citric acid which may facilitate development of a fluorescence-based sensor based on the ZnSe core-only quantum dot platform. Further, the hydrophilic core–shell structure may find use in cell imaging applications.
TL;DR: In this article, an eco-friendly procedure for synthesis of 2-(2-oxo-2H-chromen-4-yl)-3-arylthiazolidin-4 -one derivatives by three-component reaction with tetramethylbutane-1,4-diammonium acetate as a low-cost ionic liquid catalyst is described.
TL;DR: In this paper, a simple hydrothermal method by employing Zn(OAc)2, InCl3, and thioglycolic acid (TGA) as the starting reagents was used as both the sulfur source and the capping agent.
Abstract: In the present study, ZnIn2S4 quantum dot was successfully synthesized via a simple hydrothermal method by employing Zn(OAc)2, InCl3, and thioglycolic acid (TGA) as the starting reagents. TGA was used as both the sulfur source and the capping agent. The obtained ZnIn2S4 quantum dot was characterized by XRD, SEM, TEM, EDS, Pl and DRS. The ZnIn2S4 quantum dot exhibited enhanced photocatalytic activity in the degradation of methylene blue under visible light irradiation. Furthermore, to examine the solar cell application of as-synthesized ZnIn2S4 quantum dot, FTO/TiO2/ZIS-QDs/N719/Pt-FTO structure was created by deposited ZnIn2S4 film on top of the TiO2 layer by Doctor’s blade method.
TL;DR: A series of 2-aryl-3-alkanamido-4 H -thiazolidin-4-ones were synthesized from long chain fatty acid hydrazides and studied for their in vitro antibacterial activity.
TL;DR: Results showed that thioglycolic acid n-butyl ester was an effective derivatizing reagent that could be applied for arsenic speciation and using methanol as modifier of the supercritical CO2 can raise the extraction efficiency.
Abstract: A method using derivatization and supercritical fluid extraction coupled with gas chromatography was developed for the analysis of dimethylarsinate, monomethylarsonate and inorganic arsenic simultaneously in solid matrices. Thioglycolic acid n-butyl ester was used as a novel derivatizing reagent. A systematic discussion was made to investigate the effects of pressure, temperature, flow rate of the supercritical CO2 , extraction time, concentration of the modifier, and microemulsion on extraction efficiency. The application for real environmental samples was also studied. Results showed that thioglycolic acid n-butyl ester was an effective derivatizing reagent that could be applied for arsenic speciation. Using methanol as modifier of the supercritical CO2 can raise the extraction efficiency, which can be further enhanced by adding a microemulsion that contains Triton X-405. The optimum extraction conditions were: 25 MPa, 90°C, static extraction for 10 min, dynamic extraction for 25 min with a flow rate of 2.0 mL/min of supercritical CO2 modified by 5% v/v methanol and microemulsion. The detection limits of dimethylarsinate, monomethylarsonate, and inorganic arsenic in solid matrices were 0.12, 0.26, and 1.1 mg/kg, respectively. The optimized method was sensitive, convenient, and reliable for the extraction and analysis of different arsenic species in solid samples.
TL;DR: Barium molybdate (BaMoO4) nanopowder was successfully synthesized via a simple precipitation route without any surfactant as mentioned in this paper, which was applied for the facile synthesis of 2,3-diarylthiazolidin-4-one derivatives using cyclization reaction of aromatic aldehydes, aromatic amines, and thioglycolic acid under ambient condition.
Abstract: Barium molybdate (BaMoO4) nanopowder was successfully synthesized via a simple precipitation route without any surfactant. The prepared nanopowder was applied for the facile synthesis of 2,3-diarylthiazolidin-4-one derivatives using cyclization reaction of aromatic aldehydes, aromatic amines, and thioglycolic acid under ambient condition.
TL;DR: In this paper, a one-pot three-component reaction for the synthesis of 4-thiazolidinone derivatives has been established by reacting readily available and inexpensive starting materials of amines, aldehydes and thioglycolic acid using Y(OTf)3 (5 mol%) as catalyst in tetrahydrofuran.
TL;DR: In this article, the effect of N 2 gas bubbling, insertion of thioglycolic acid (TGA) and cobalt doping with Co/Zn= x : 0, 0.1%, 0.3%, and 0.5% was studied by means of scanning electron microscopy, transmission electron microscope, x-ray diffraction, Furrier transformed infrared(FTIR) spectroscopy, UV-Vis spectroscope and photoluminescence (PL) measurement.
TL;DR: Combining organic and inorganic semiconductors leads to increase of the effective absorption cross section of the QDs which can be utilized in novel nanoscale designs for light-emitting, photovoltaic and sensor applications.
TL;DR: It was found that compound 3b was the most potent antibacterial compound which showed good activity against four Gram positive bacterial strains and also exhibited excellent antifungal activity against a fungal strain.
TL;DR: In this paper, the acid hydrazide derivatives were converted into pyrazolone, triazinone, and schiff bases, and the structures of newly synthesized compounds were established on the basis of IR, 1H-NMR, mass spectral data, and elemental analyses.
TL;DR: In this paper, the reaction of tripropylammonium fluorochromate (TriPAFC) and thioacids in N, N -dimethyl formamide (DMF) has been studied.
Patent•
09 Nov 2016TL;DR: In this article, an imidazopyridine thioglycolic acid derivative and a preparation method and application thereof were described and an application of the compound in preparation of drugs for resisting gout.
Abstract: The invention relates to an imidazopyridine thioglycolic acid derivative and a preparation method and application thereof. The compound has the structure as shown in a formula I or a formula II or a formula III. The invention further relates to a preparation method of the compound with the structure as shown in the formula I or the formula II or the formula III and pharmaceutical compositions. The invention further provides application of the compound in preparation of drugs for resisting gout. Please see the formula in the description.
TL;DR: 2(3H)-Furanone 1 was utilized for the construction of thiazolidinone derivatives and some of the tested compounds showed promising activities.
TL;DR: A dual-channel optical sensing platform which combines the advantages of dual-wavelength overlapping resonance Rayleigh scattering (DWO-RRS) and fluorescence has been designed for the detection of diminazene aceturate (DA) with satisfactory results.