Knight Shift in 13 C NMR Resonances Confirms the Coordination of N‐Heterocyclic Carbene Ligands to Water‐Soluble Palladium Nanoparticles

2016 ◽  
Vol 56 (3) ◽  
pp. 865-869 ◽  
Author(s):  
Juan M. Asensio ◽  
Simon Tricard ◽  
Yannick Coppel ◽  
Román Andrés ◽  
Bruno Chaudret ◽  
...  
Keyword(s):  
Palladium Nanoparticles ◽  
Knight Shift ◽  
Water Soluble ◽  
Carbene Ligands ◽  
C Nmr

Knight Shift in 13 C NMR Resonances Confirms the Coordination of N‐Heterocyclic Carbene Ligands to Water‐Soluble Palladium Nanoparticles

2016 ◽  
Vol 129 (3) ◽  
pp. 883-887 ◽  
Author(s):  
Juan M. Asensio ◽  
Simon Tricard ◽  
Yannick Coppel ◽  
Román Andrés ◽  
Bruno Chaudret ◽  
...  
Keyword(s):  
Palladium Nanoparticles ◽  
Knight Shift ◽  
Water Soluble ◽  
Carbene Ligands ◽  
C Nmr

Glucan isolated from leaves of Althaea officinalis L.

1983 ◽  
Vol 48 (7) ◽  
pp. 2082-2087 ◽  
Author(s):  
Alžbeta Kardošová ◽  
Jozef Rosík ◽  
Rudolf Toman ◽  
Peter Capek
Keyword(s):  
Medicinal Plant ◽  
Periodate Oxidation ◽  
Linear Structure ◽  
Water Soluble ◽  
Partial Hydrolysis ◽  
Methylation Analysis ◽  
Glycosidic Bonds ◽  
Nmr Data ◽  
Althaea Officinalis ◽  
C Nmr

A water-soluble low-molecular D-glucan was isolated from leaves of the medicinal plant marsh-mallow (Althaea officinalis L.). The results of methylation analysis, partial hydrolysis, periodate oxidation, and 13C NMR data indicated a virtually linear structure with α-(1→6) glycosidic bonds.

scholarly journals Polyethyleneimine-Oleic Acid Micelles-Stabilized Palladium Nanoparticles as Highly Efficient Catalyst to Treat Pollutants with Enhanced Performance

Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1890
Author(s):  
Xiang Lai ◽  
Xuan Zhang ◽  
Shukai Li ◽  
Jie Zhang ◽  
Weifeng Lin ◽  
...  
Keyword(s):  
Oleic Acid ◽  
Metal Nanoparticles ◽  
Noble Metal ◽  
Palladium Nanoparticles ◽  
Human Life ◽  
Catalytic Performance ◽  
Water Soluble ◽  
Noble Metal Nanoparticles ◽  
Hydrodynamic Diameter ◽  
Efficient Catalyst

Water soluble organic molecular pollution endangers human life and health. It becomes necessary to develop highly stable noble metal nanoparticles without aggregation in solution to improve their catalytic performance in treating pollution. Polyethyleneimine (PEI)-based stable micelles have the potential to stabilize noble metal nanoparticles due to the positive charge of PEI. In this study, we synthesized the amphiphilic PEI-oleic acid molecule by acylation reaction. Amphiphilic PEI-oleic acid assembled into stable PEI-oleic acid micelles with a hydrodynamic diameter of about 196 nm and a zeta potential of about 34 mV. The PEI-oleic acid micelles-stabilized palladium nanoparticles (PO-PdNPsn) were prepared by the reduction of sodium tetrachloropalladate using NaBH4 and the palladium nanoparticles (PdNPs) were anchored in the hydrophilic layer of the micelles. The prepared PO-PdNPsn had a small size for PdNPs and good stability in solution. Noteworthily, PO-PdNPs150 had the highest catalytic activity in reducing 4-nitrophenol (4-NP) (Knor = 18.53 s−1mM−1) and oxidizing morin (Knor = 143.57 s−1M−1) in aqueous solution than other previous catalysts. The enhanced property was attributed to the improving the stability of PdNPs by PEI-oleic acid micelles. The method described in this report has great potential to prepare many kinds of stable noble metal nanoparticles for treating aqueous pollution.

Synthesis and Characterization of Highly Water Soluble Ruthenium(II) and Osmium(II) Complexes Bearing Chelating Sulfonated N-Heterocyclic Carbene Ligands

2013 ◽  
Vol 32 (3) ◽  
pp. 741-744 ◽  
Author(s):  
Dominik Jantke ◽  
Mirza Cokoja ◽  
Alexander Pöthig ◽  
Wolfgang A. Herrmann ◽  
Fritz E. Kühn
Keyword(s):  
Water Soluble ◽  
Synthesis And Characterization ◽  
Carbene Ligands

scholarly journals Peptide-coated palladium nanoparticle for highly sensitive bioanalysis of trypsin in human urine samples

2018 ◽  
Vol 8 ◽  
pp. 184798041882039 ◽  
Author(s):  
Guohua Zhou ◽  
Huimin Jiang ◽  
Yanfang Zhou ◽  
Peilian Liu ◽  
Yongmei Jia ◽  
...  
Keyword(s):  
Energy Transfer ◽  
Fluorescence Resonance Energy Transfer ◽  
Palladium Nanoparticles ◽  
Limit Of Detection ◽  
Resonance Energy Transfer ◽  
Resonance Energy ◽  
Water Soluble ◽  
Urine Samples ◽  
Fluorescence Resonance ◽  
Functional Peptide

In recent years, palladium nanoparticles have been proved as energy acceptor candidates in fluorescence resonance energy transfer-based sensors for analytical and biological purposes. In this article, peptide-coated palladium nanoparticles were prepared using a simple one-step preparation method. The peptide Cys-Ala-Leu-Asn-Asn was used as a ligand, whereas hydrazine hydrate was used as a reductant to obtain water-soluble and stable peptide-coated palladium nanoparticles. Additionally, peptide-coated palladium nanoparticles were functionalized by adding the functional peptide CALNNGGARK(FITC) in combination with Cys-Ala-Leu-Asn-Asn during the preparation process. The prepared functionalized peptide-coated palladium nanoparticles were used for trypsin detection based on the fluorescence resonance energy transfer approach. Under optimized conditions, the proposed method can be used for the detection of trypsin concentrations in the range of approximately 0.2–8-μg/mL with a limit of detection of 0.18-μg/mL. The functionalized peptide-coated palladium nanoparticles were successfully applied for the detection of trypsin in urine samples. Our findings also indicated that peptide-coated palladium nanoparticles can highly quench fluorophores and are suitable for the manufacture of off–on state fluorescent sensors. We anticipated that the peptide-coated palladium nanoparticles proposed in this article will have great potential for the detection of trypsin in urine and other analytical, biological, and clinical applications.

Sonogashira reactions catalyzed by water-soluble, β-cyclodextrin-capped palladium nanoparticles

2007 ◽  
Vol 116 (3-4) ◽  
pp. 94-100 ◽  
Author(s):  
Cuihua Xue ◽  
Kumaranand Palaniappan ◽  
Ganesh Arumugam ◽  
Stephen A. Hackney ◽  
Jian Liu ◽  
...  
Keyword(s):  
Palladium Nanoparticles ◽  
Water Soluble ◽  
Sonogashira Reactions

Analysis of the substituent distribution along the chain of water-soluble methyl cellulose by combination of enzymatic and chemical methods

Holzforschung ◽  
2004 ◽  
Vol 58 (1) ◽  
pp. 97-104 ◽  
Author(s):  
B. Saake ◽  
S. Lebioda ◽  
J. Puls
Keyword(s):  
Anion Exchange ◽  
Size Exclusion Chromatography ◽  
Methyl Cellulose ◽  
Anion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Degree Of Substitution ◽  
Water Soluble ◽  
Size Exclusion ◽  
Exclusion Chromatography ◽  
C Nmr

Abstract Four methyl cellulose samples in the degree of substitution range from 0.5 to 2.0 were characterised by combination of different analytical methods. Samples were analysed regarding their partial degree of substitution by hydrolysis and anion exchange chromatography with pulsed amperometric detection. For calibration of the chromatographic system, standard substances were isolated by preparative HPLC and their structure was confirmed by 13C-NMR spectroscopy. For two methyl cellulose samples per-acetylation and 13C-NMR with inverse gated decoupling was carried out for comparison with the chromatographic analysis. Endoglucanase fragmentation of methyl celluloses was performed and water-soluble and insoluble fractions were analysed separately. A preparative size exclusion chromatography system for enzymatic-degraded water-soluble methyl cellulose was developed and the molar masses of the individual fractions were examined by analytical size exclusion chromatography. By combination of endoglucanase fragmentation, preparative chromatography, hydrolysis and anion exchange chromatography an approach for the analysis of the substitutent distribution along the polymeric chain of water-soluble methyl cellulose could be established.

Water-Soluble Palladium Nanoparticles: Click Synthesis and Applications as a Recyclable Catalyst in Suzuki Cross-Couplings in Aqueous Media

2010 ◽  
Vol 2010 (26) ◽  
pp. 5090-5099 ◽  
Author(s):  
Nereida Mejías ◽  
Roser Pleixats ◽  
Alexandr Shafir ◽  
Mercedes Medio-Simón ◽  
Gregorio Asensio
Keyword(s):  
Palladium Nanoparticles ◽  
Aqueous Media ◽  
Recyclable Catalyst ◽  
Water Soluble ◽  
Click Synthesis

scholarly journals Aqueous-biphasic hydroformylation of 1-hexene catalyzed by the complex HCo(CO)[P(o-C6H4SO3Na)]3

2017 ◽  
Vol 61 (2) ◽  
Author(s):  
María Modroño-Alonso ◽  
William Castro ◽  
Francisco Lopez-Linares ◽  
Merlín Rosales ◽  
Pablo Jose Baricelli
Keyword(s):  
Cobalt Complex ◽  
Nitrogen Atmosphere ◽  
Water Soluble ◽  
Catalyst Precursor ◽  
Reaction Conditions ◽  
Moderate Reaction ◽  
H Nmr ◽  
Reductive Carbonylation ◽  
Aqueous Biphasic ◽  
C Nmr

The water soluble cobalt complex HCo(CO)[P(<em>o</em>-C<sub>6</sub>H<sub>4</sub>SO-<sub>3</sub>Na)]<sub>3</sub> was used as catalyst precursor for the biphasic aqueous hydroformylation of 1-hexene. The complex was synthesized by reductive carbonylation of CoCl<sub>2</sub>.6H<sub>2</sub>O in the presence of <em>o</em>-TPPTS ([P(<em>o</em>-C<sub>6</sub>H<sub>4</sub>SO<sub>3</sub>Na)]<sub>3</sub>) under nitrogen atmosphere and characterized by FTIR, <sup>1</sup>H NMR and <sup>31</sup>P {1H} NMR, <sup>13</sup>C NMR, DEPT – 135, COSY, HSQC, MS (ESI). The catalytic activity of the complex in the biphasic hydroformylation reaction of 1-hexene was evaluated under moderate reaction conditions. The pressure and temperature were varied from 4137 – 7584 kPa (600-1100 psi) of syngas and from 353 – 383 K (80 – 110 °C), respectively. The 1-hexene concentration was varied from 0.021-0,11M and the catalyst from 4x10<sup>-4</sup> - 1.1x10<sup>-3</sup> M. The best conversion at 363 K and 7584 kPa and 7.5 h was 62% with selectivity towards aldehydes (heptanal and 2-methyl-hexanal) of 66% to with l/b ratio of 2.6. The recycling of the catalytic precursor after four successive times, did not show any loss on the activity, having selectivity towards aldehyde up to 60%.

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