Synthesis and characterization of carbonate-encapsulated ytterbium- and yttrium-containing polyoxotungstates

A sandwiched-type carbonate-encapsulated yttrium-containing arsenotungstate(III) has been synthesized under mild reaction conditions. The polyanion [NaCH3COO{Y2(H2O)3(B-α-AsW9O33)2(W2O5)(CO3)}]12− (1) was isolated as a solid crystalline material by the reaction of a YIII salt with the sodium salt of trilacunary [AsW9O33]9− in sodium acetate solution. The sodium salt of the polyanion, i.e. Na12[Na(CH3COO){Y2(AsW9O33)2(W2O5)(CO3)(H3O)3}]·22H2O (1a), was characterized by various analytical techniques, such as FT–IR, single-crystal X-ray diffraction (SC–XRD), TGA (thermogravimetric analysis), 13C NMR and ESI–MS (electrospray ionization mass spectrometry). SC–XRD studies revealed that the polyanion crystallizes in the triclinic space group P\overline{1}. The structure showed that the polyanion is a carbonate-encapsulated sandwich-type species, consisting of two trilacunary B-α-[AsW9O33]9−, with a lone-pair-containing AsIII heteroatom, together with two extra tungsten centres and two yttrium cations at the sandwich position, where CH3COO− and Na+ ions act as linkers between the two polyanion units. In addition, we have also synthesized two carbonate-encapsulated germanotungstates(IV), without lone-pair-containing heteroatoms, with the formula [Ln3(A-β-GeW9O34)2(CO3)(H2O)3]13− [Ln = YIII (2) and YbIII (3)], i.e. Y2K3Na4[Y3(A-β-GeW9O34)2(CO3)(H2O)3]·19H2O (2a) and YbK8Na2[Yb(A-β-GeW9O34)2(CO3)(H2O)3]·16H2O (3a), and characterized them by FT–IR, SC–XRD, TGA and ESI–MS. Here, the lanthanide ions act as linkers, extending the structures into higher dimensions. Sodium and potassium ions also play a key role as linkers, further extending the structure. The packing shows the presence of certain hydrophilic pores within the structure.

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A highly sensitive octopus-like azobenzene fluorescent probe for determination of abamectin B1 in apples

Scientific Reports ◽

10.1038/s41598-021-84221-w ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Zhenlong Guo ◽

YiFei Su ◽

Kexin Li ◽

MengYi Tang ◽

Qiang Li ◽

...

Keyword(s):

Fluorescent Probe ◽

Limit Of Detection ◽

Quantitative Detection ◽

Fluorescence Signal ◽

Ionization Mass ◽

Limit Of Quantification ◽

Visible Absorption ◽

Esi Ms ◽

Relative Standard ◽

Ft Ir

AbstractThe development of detecting residual level of abamectin B1 in apples is of great importance to public health. Herein, we synthesized a octopus-like azobenzene fluorescent probe 1,3,5-tris (5′-[(E)-(p-phenoxyazo) diazenyl)] benzene-1,3-dicarboxylic acid) benzene (TPB) for preliminary detection of abamectin B1 in apples. The TPB molecule has been characterized by ultraviolet–visible absorption spectrometry, 1H-nuclear magnetic resonance, fourier-transform infrared (FT-IR), electrospray ionization mass spectroscopy (ESI-MS) and fluorescent spectra. A proper determination condition was optimized, with limit of detection and limit of quantification of 1.3 µg L−1 and 4.4 μg L−1, respectively. The mechanism of this probe to identify abamectin B1 was illustrated in terms of undergoing aromatic nucleophilic substitution, by comparing fluorescence changes, FT-IR and ESI-MS. Furthermore, a facile quantitative detection of the residual abamectin B1 in apples was achieved. Good reproducibility was present based on relative standard deviation of 2.2%. Six carboxyl recognition sites, three azo groups and unique fluorescence signal towards abamectin B1 of this fluorescent probe demonstrated reasonable sensitivity, specificity and selectivity. The results indicate that the octopus-like azobenzene fluorescent probe can be expected to be reliable for evaluating abamectin B1 in agricultural foods.

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The Basis of Bentazon Antagonism on Sethoxydim Absorption and Activity

Weed Science ◽

10.1017/s004317450007212x ◽

1989 ◽

Vol 37 (3) ◽

pp. 400-404 ◽

Cited By ~ 45

Author(s):

Gunawan Wanamarta ◽

Donald Penner ◽

James J. Kells

Keyword(s):

Sodium Salt ◽

Sodium Acetate ◽

Tomato Fruit ◽

Weak Acid ◽

Antagonistic Effect ◽

Hydroxyl Group ◽

Sodium Acetate Solution ◽

Acetate Solution ◽

Spray Solution ◽

Leaf Surfaces

The antagonistic effect of bentazon on sethoxydim adsorption and activity was studied in quackgrass. The diffusion of14C-sethoxydim into and through an isolated tomato fruit cuticle was inhibited in the presence of the sodium salt of bentazon. Bentazon also increased the partitioning of14C-sethoxydim into CH2Cl2and water; however, it decreased partitioning into ethyl acetate. Removal of epicuticular wax from quackgrass leaf surfaces did not prevent the antagonism. Addition of sodium acetate or sodium bicarbonate to the sethoxydim spray solution at 10 mM reduced uptake of14C-sethoxydim by quackgrass similar to the effect of bentazon. Sodium ions in the bentazon formulation appeared responsible for the antagonism by exchanging with the H+of the sethoxydim hydroxyl group to form a more polar sodium salt of sethoxydim. The addition of Li+, K+, Cs+, Ca++, and Mg++cations associated with a weak acid also reduced14C-sethoxydim absorption. Addition of organic acids to the spray solution overcame the antagonism by preventing the formation of sodium salt of sethoxydim. In the field, the addition of a 3000 ppm sodium acetate solution delivering 0.56 kg/ha produced the same antagonism as bentazon on quackgrass control with sethoxydim.

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Study on Soy-Based Adhesives Enhanced by Phenol Formaldehyde Cross-Linker

Polymers ◽

10.3390/polym11020365 ◽

2019 ◽

Vol 11 (2) ◽

pp. 365 ◽

Cited By ~ 7

Author(s):

Zhigang Wu ◽

Xuedong Xi ◽

Hong Lei ◽

Jiankun Liang ◽

Jingjing Liao ◽

...

Keyword(s):

13C Nmr ◽

Soy Protein ◽

Water Resistance ◽

Phenol Formaldehyde ◽

Ionization Mass ◽

Model Compounds ◽

Esi Ms ◽

13C Nuclear Magnetic Resonance ◽

Ft Ir ◽

Cross Linker

To find the effects of cross-linker phenol-formaldehyde (PF) resin on the performance of soy-based adhesives, the reaction between model compounds hydroxymethyl phenol (HPF) and glutamic acid were studied in this paper. HPF prepared in laboratory conditions showed higher content of hydroxymethyl groups than normal PF resin, which was proved by the results of Electrospray Ionization Mass Spectrometry (ESI-MS) and 13C Nuclear Magnetic Resonance (13C-NMR). The results of ESI-MS, Fourier transform infrared spectroscopy (FT-IR), and 13C-NMR based on resultant products obtained from model compounds showed better water resistance of the soy protein-based adhesive modified by PF-based resin, which indicated the reaction between PF resin and soy protein. However, it seemed that the soy-based adhesive cross-linked by HPF with the maximum content of hydroxymethyl groups did not show the best water resistance.

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Conformational Analysis and Binding Affinity Determination for Host—Guest Complexation of Alkali Metal Ions with Bis-Crown Ethers by Electrospray Mass Spectrometry and Molecular Modeling

European Journal of Mass Spectrometry ◽

10.1255/ejms.516 ◽

2002 ◽

Vol 8 (5) ◽

pp. 375-380 ◽

Cited By ~ 9

Author(s):

Hui-Fen Wu ◽

Shun-Min Huan ◽

Chun-Fu Wu

Keyword(s):

Mass Spectrometry ◽

Alkali Metal ◽

Metal Ions ◽

Binding Affinity ◽

Alkali Metal Ions ◽

Ionization Mass ◽

Potassium Ions ◽

Esi Ms ◽

Sandwich Type

This study presents the application of electrospray ionization mass spectrometry (ESI/MS) to investigate the host–guest complexation phenomenon for an array of alkali metal ions with bis[(benzo-15–crown-5)-15–ylmethyl] pimelate (BBCP). The results have shown that potassium ions possess the best binding affinity with the BBCP, owing to formation of the very stable sandwich-type (1:1) complexes and the strong K+ cation-π electron interactions between the K+ ion and the benzene rings of BBCP. The results of the competition experiments indicate the selectivity for BBCP toward the alkali metal ions is K+ > Rb+ > Cs+ > Na+ > Li+. In addition, combining the results of ESI/MS and molecular mechanics conformational searches reveal that the formation of sandwich-type (1:1) complexes can be observed for larger metal ions including K+, Rb+ and Cs+. As for Na+ ions, both 1:1 and 1:2 complexes can be observed.

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A highly sensitive octopus-like azobenzene fluorescent probe for determination of abamectin B1 in apples

10.21203/rs.3.rs-109482/v1 ◽

2020 ◽

Author(s):

Zhenlong Guo ◽

YiFei Su ◽

Kexin Li ◽

MengYi Tang ◽

Qiang Li ◽

...

Keyword(s):

Fluorescent Probe ◽

Limit Of Detection ◽

Quantitative Detection ◽

Fluorescence Signal ◽

Ionization Mass ◽

Limit Of Quantification ◽

Visible Absorption ◽

Esi Ms ◽

Relative Standard ◽

Ft Ir

Abstract The development of detecting residual level of abamectin B1 in apples is of great importance to public health. Herein, we synthesized a octopus-like azobenzene fluorescent probe 1,3,5-tris (5'-[(E)-(p-phenoxyazo) diazenyl)] benzene-1,3-dicarboxylic acid) benzene (TPB) for preliminary detection of abamectin B1 in apples. The TPB molecule was characterized by ultraviolet-visible absorption spectrometry, 1H-nuclear magnetic resonance, fourier-transform infrared (FT-IR), electrospray ionization mass spectroscopy (ESI-MS) and fluorescent spectrum. A proper determination condition was optimized, with limit of detection and limit of quantification of 1.3 µg L-1 and 4.4 μg L-1, respectively. The mechanism of this probe to identify abamectin B1 was illustrated in terms of undergoing aromatic nucleophilic substitution, by comparing fluorescence changes, FT-IR and ESI-MS. Furthermore, a facile quantitative detection of the residual abamectin B1 in apples was achieved. Good reproducibility was shown based on relative standard deviation of 2.20%. Six carboxyl recognition sites, three azo groups and unique fluorescence signal towards abamectin B1 of this fluorescent probe decided ideal sensitivity, specificity and selectivity. The results show that the octopus-like azobenzene fluorescent probe may be promising for evaluating abamectin B1 in agricultural foods.

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Mass spectrometry-based procedure for the identification of ovine casein heterogeneity

Journal of Dairy Research ◽

10.1017/s0022029900004611 ◽

2001 ◽

Vol 68 (1) ◽

pp. 35-51 ◽

Cited By ~ 23

Author(s):

PASQUALE FERRANTI ◽

ROSA PIZZANO ◽

GIUSEPPINA GARRO ◽

SIMONETTA CAIRA ◽

LINA CHIANESE ◽

...

Keyword(s):

Mass Spectrometry ◽

Analytical Techniques ◽

Reversed Phase ◽

Ionization Mass ◽

Esi Ms ◽

On Line ◽

Protein Components ◽

Rapid Characterization ◽

A Minor ◽

Reference Tools

The efficiency of reversed-phase HPLC, capillary electrophoresis (CE), PAGE and isoelectric focusing with immunoblotting in separating ovine caseins has been evaluated. The assessment was carried out by employing electrospray ionization–mass spectrometry (ESI–MS) and matrix-assisted laser desorption ionization–time of flight as reference tools for identifying protein components. Ovine casein was fractionated by HPLC into four major peaks. With ESI–MS, each peak contained components belonging to only one of the four casein families. On-line liquid chromatography–ESI–MS allowed us to determine each fraction's composition by detecting thirteen αs1-, eleven αs2-, seven β-, and three κ-casein (CN) components. The αs1-CN and αs2-CN consisted of eight and two protein chains respectively of lengths differing through the deletion of one or more peptide sequences; they were also discretely phosphorylated as κ-CN and β-CN. By CE at pH 2·5, each casein fraction was as heterogeneous as that resulting from ESI–MS for the single HPLC-derived fractions. The separation of αs1-CN and αs2-CN proved to be excellent, with the exception of a co-migration of κ0-CN with a minor αs1-CN component and of a glycosylated κ-CN form with low-phosphorylated αs1-CN and β-CN components. Dephosphorylation of whole casein was used to reduce the heterogeneity of the native fractions and by applying currently used analytical techniques it was possible to visualize the protein moiety difference along the CE profile. CE, HPLC, and immunoblotting were all equally capable of effecting an accurate separation of the four dephosphorylated casein families. The spectra obtained by ESI–MS directly on dephosphorylated whole ovine casein samples contained the signals of the four casein families and the relative αs1-CN variants, the non-allelic αs1-CN and αs2-CN forms, dimeric κ-CN and other newly formed peptides. We suggest using this procedure for rapid characterization of whole casein.

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Chitosan hydrogel/silk fibroin/Mg(OH)2 nanobiocomposite as a novel scaffold with antimicrobial activity and improved mechanical properties

Scientific Reports ◽

10.1038/s41598-020-80133-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Reza Eivazzadeh-Keihan ◽

Fateme Radinekiyan ◽

Hooman Aghamirza Moghim Aliabadi ◽

Sima Sukhtezari ◽

Behnam Tahmasebi ◽

...

Keyword(s):

Antibacterial Activity ◽

Cell Viability ◽

Silk Fibroin ◽

Analytical Techniques ◽

Structural Features ◽

Mechanical Tests ◽

Chitosan Hydrogel ◽

Biological Capacity ◽

Ft Ir ◽

Novel Scaffold

AbstractHerein, a novel nanobiocomposite scaffold based on modifying synthesized cross-linked terephthaloyl thiourea-chitosan hydrogel (CTT-CS hydrogel) substrate using the extracted silk fibroin (SF) biopolymer and prepared Mg(OH)2 nanoparticles was designed and synthesized. The biological capacity of this nanobiocomposite scaffold was evaluated by cell viability method, red blood cells hemolytic and anti-biofilm assays. According to the obtained results from 3 and 7 days, the cell viability of CTT-CS/SF/Mg(OH)2 nanobiocomposite scaffold was accompanied by a considerable increment from 62.5 to 89.6% respectively. Furthermore, its low hemolytic effect (4.5%), and as well, the high anti-biofilm activity and prevention of the P. aeruginosa biofilm formation confirmed its promising hemocompatibility and antibacterial activity. Apart from the cell viability, blood biocompatibility, and antibacterial activity of CTT-CS/SF/Mg(OH)2 nanobiocomposite scaffold, its structural features were characterized using spectral and analytical techniques (FT-IR, EDX, FE-SEM and TG). As well as, given the mechanical tests, it was indicated that the addition of SF and Mg(OH)2 nanoparticles to the CTT-CS hydrogel could improve its compressive strength from 65.42 to 649.56 kPa.

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Structure of aqueous sodium acetate solutions by X-Ray scattering and density functional theory

Pure and Applied Chemistry ◽

10.1515/pac-2020-0402 ◽

2020 ◽

Vol 92 (10) ◽

pp. 1627-1641

Author(s):

Guangguo Wang ◽

Yongquan Zhou ◽

He Lin ◽

Zhuanfang Jing ◽

Hongyan Liu ◽

...

Keyword(s):

Sodium Acetate ◽

Density Functional ◽

Hydration Shell ◽

Ion Pair ◽

Water Molecules ◽

Sodium Acetate Solution ◽

Acetate Solution ◽

X Ray ◽

X Ray Scattering ◽

Ray Scattering

AbstractThe structure of aq. sodium acetate solution (CH3COONa, NaOAc) was studied by X-ray scattering and density function theory (DFT). For the first hydrated layer of Na+, coordination number (CN) between Na+ and O(W, I) decreases from 5.02 ± 0.85 at 0.976 mol/L to 3.62 ± 1.21 at 4.453 mol/L. The hydration of carbonyl oxygen (OC) and hydroxyl oxygen (OOC) of CH3COO− were investigated separately and the OC shows a stronger hydration bonds comparing with OOC. With concentrations increasing, the hydration shell structures of CH3COO− are not affected by the presence of large number of ions, each CH3COO− group binds about 6.23 ± 2.01 to 7.35 ± 1.73 water molecules, which indicates a relatively strong interaction between CH3COO− and water molecules. The larger uncertainty of the CN of Na+ and OC(OOC) reflects the relative looseness of Na-OC and Na-OOC ion pairs in aq. NaOAc solutions, even at the highest concentration (4.453 mol/L), suggesting the lack of contact ion pair (CIP) formation. In aq. NaOAc solutions, the so called “structure breaking” property of Na+ and CH3COO− become effective only for the second hydration sphere of bulk water. The DFT calculations of CH3COONa (H2O)n=5–7 clusters suggest that the solvent-shared ion pair (SIP) structures appear at n = 6 and become dominant at n = 7, which is well consistent with the result from X-ray scattering.

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Multifunctional application of PVA-aided Zn–Fe–Mn coupled oxide nanocomposite

Nanoscale Research Letters ◽

10.1186/s11671-020-03464-0 ◽

2021 ◽

Vol 16 (1) ◽

Author(s):

Buzuayehu Abebe ◽

H. C. Ananda Murthy ◽

Enyew Amare Zereffa

Keyword(s):

Charge Transfer ◽

Analytical Techniques ◽

Antibacterial Activities ◽

Poly Vinyl Alcohol ◽

Blue Dye ◽

Ternary Oxide ◽

Gram Positive Bacteria ◽

Transfer Capability ◽

Ft Ir ◽

Synthesized Materials

AbstractZinc oxide (ZnO) is a fascinating semiconductor material with many applications such as adsorption, photocatalysis, sensor, and antibacterial activities. By using a poly (vinyl alcohol) (PVA) polymer as a capping agent and metal oxides (iron and manganese) as a couple, the porous PVA-aided Zn/Fe/Mn ternary oxide nanocomposite material (PTMO-NCM) was synthesized. The thermal, optical, crystallinity, chemical bonding, porosity, morphological, charge transfer properties of the synthesized materials were confirmed by DTG/DSC, UV–Vis-DRS, XRD, FT-IR, BET, SEM-EDAX/TEM-HRTEM-SAED, and CV/EIS/amperometric analytical techniques, respectively. The PTMO-NCM showed an enhanced surface area and charge transfer capability, compared to ZnO. Using the XRD pattern and TEM image analysis, the crystalline size of the materials was confirmed to be in the nanometer range. The porosity and superior charge transfer capabilities of the PTMO-NCM were confirmed from the BET, HRTEM (IFFT)/SAED, and CV/EIS analysis. The adsorption kinetics (adsorption reaction/adsorption diffusion) and adsorption isotherm test confirmed the presence of a chemisorption type of adsorbate/methylene blue dye-adsorbent/PTMO-NCM interaction. The photocatalytic performance was tested on the Congo red and Acid Orange-8 dyes. The superior ascorbic acid sensing capability of the material was understood from CV and amperometric analysis. The noble antibacterial activities of the material were also confirmed on both gram-negative and gram-positive bacteria.

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