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101.
May Lee Low Cheang Wei Chan Pei Ying Ng Ing Hong Ooi Mohd Jamil Maah Soi Moi Chye 《Journal of Coordination Chemistry》2017,70(2):223-241
Three ternary copper(II) complexes, [Cu(phen)(L-phe)Cl]·2H2O, [Cu(phen)(L-leu)Cl]·4½H2O, and [Cu(phen)(L-tyr)Cl]·3H2O, and four binary copper(II) complexes, [Cu(phen)Cl2], Cu(L-phe)2·½H2O, Cu(L-leu)2·½H2O, and Cu(L-tyr)2·H2O (where phen = 110-phenanthroline, L-phe = L-phenylalanine, L-tyr = L-tyrosine, L-leu = L-leucine and Cl- = chloride), were synthesized and characterized by elemental analysis, spectroscopic techniques (FTIR, UV–visible, fluorescence spectroscopy), magnetic susceptibility, molar conductivity, and lipophilicity measurement. X-ray diffraction determination of a single crystal of [Cu(phen)(L-tyr)Cl] showed two independent molecules in the asymmetric unit, each with the same distorted square pyramidal geometry about copper(II). p-Nitrosodimethylaniline assay revealed that the three ternary complexes were better inducers of reactive oxygen species over time than binary complexes, CuCl2, and free ligands. All the copper(II) complexes in this series inhibited the three proteolytic activities in the order Trypsin-like > Caspase-like > Chymotrypsin-like. In terms of anticancer properties, the copper(II)-phen complexes had GI50 values of less than 4 μM against MCF-7, HepG2, CNE1 and A549 cancer cell lines, more potent than cisplatin. 相似文献
102.
Idris Mohd Srivastava Seema Baggi Tulsidas R. Shukla Sudhir Kumar 《平面色谱法杂志一现代薄层色谱法》2010,23(5):339-342
JPC – Journal of Planar Chromatography – Modern TLC - A simple, accurate, and inexpensive high-performance thin-layer chromatography (HPTLC) method has been established for analysis of... 相似文献
103.
Mohd Rafein Zakaria Hidayah Ariffin Suraini Abd-Aziz Yoshihito Shirai 《Polymer Degradation and Stability》2010,95(8):1382-1386
Poly(3-hydroxybutyrate) [P(3HB)] homopolymer and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(3HB-co-3HV)] copolymer was produced by Comamonas sp. EB172 using single and mixture of carbon sources. Poly(3-hydroxyvalerate) P(3HV) incorporation in the copolymer was obtained when propionic and valeric acid was used as precursors. Incorporation of 3HV fractions in the copolymer varied from 45 to 86 mol% when initial pH of the medium was regulated. In fed-batch cultivation, organic acids derived from anaerobically treated palm oil mill effluent (POME) were shown to be suitable carbon sources for polyhydroxyalkanoate (PHA) production by Comamonas sp. EB172. Number average molecular weight (Mn) produced by the strain was in the range of 153-412 kDa with polydispersity index (Mw/Mn) in the range of 2.2-2.6, respectively. Incorporation of higher 3HV units improved the thermal stability of P(3HB-co-3HV) copolymer. Thus the newly isolated bacterium Comamonas sp. EB172 is a suitable candidate for PHA production using POME as renewable and alternative cheap raw materials. 相似文献
104.
105.
Nicolas Droushiotis Uttam Doraswami Douglas Ivey Mohd Hafiz Dzarfan Othman Kang Li Geoff Kelsall 《Electrochemistry communications》2010,12(6):792-795
A phase inversion process was used to co-extrude cerium–gadolinium oxide (Ce0.9Gd0.1O1.95)/NiO–CGO dual-layer hollow fibres (HF), which were then sintered to form, respectively, the electrolyte and high porosity anode precursor of a solid oxide fuel cell (SOFC) with anode inner diameter of 0.8 mm. Graded CGO–lanthanum strontium cobalt ferrite (La0.6Sr0.4Fe0.8Co0.2O3) cathode layers were then painted onto the CGO electrolyte to form a micro-tubular HF-SOFC. With a carefully designed anode current collector, this produced maximum power densities of 1186–5864 W m? 2 at 450–570 °C. High magnification imaging analysis revealed large three-phase boundary regions within the anode, a dense electrolyte layer and clearly highlighted the multiple CGO–LSCF cermet and pure LSCF cathode layers. The performance of the HF-SOFC with a twenty millimetre active length showed no degradation after four thermal cycles between 300 °C and 570 °C. 相似文献
106.
Mohd Marsin Sanagi Mazidatulakmam Miskam Wan Aini Wan Ibrahim Dadan Hermawan Hassan Y. Aboul‐Enein 《Journal of separation science》2010,33(14):2131-2139
A three‐phase hollow fiber liquid‐phase microextraction method coupled with CE was developed and used for the determination of partition coefficients and analysis of selected nitrophenols in water samples. The selected nitrophenols were extracted from 14 mL of aqueous solution (donor solution) with the pH adjusted to pH 3 into an organic phase (1‐octanol) immobilized in the pores of the hollow fiber and finally backextracted into 40.0 μL of the acceptor phase (NaOH) at pH 12.0 located inside the lumen of the hollow fiber. The extractions were carried out under the following optimum conditions: donor solution, 0.05 M H3PO4, pH 3.0; organic solvent, 1‐octanol; acceptor solution, 40 μL of 0.1 M NaOH, pH 12.0; agitation rate, 1050 rpm; extraction time, 15 min. Under optimized conditions, the calibration curves for the analytes were linear in the range of 0.05–0.30 mg/L with r2>0.9900 and LODs were in the range of 0.01–0.04 mg/L with RSDs of 1.25–2.32%. Excellent enrichment factors of up to 398‐folds were obtained. It was found that the partition coefficient (Ka/d) values were high for 2‐nitrophenol, 3‐nitrophenol, 4‐nitrophenol, 2,4‐dinitrophenol and 2,6‐dinitrophenol and that the individual partition coefficients (Korg/d and Ka/org) promoted efficient simultaneous extraction from the donor through the organic phase and further into the acceptor phase. The developed method was successfully applied for the analysis of water samples. 相似文献
107.
Nazim Hasan Hui-Fen Wu Yi-Hsien Li Mohd Nawaz 《Analytical and bioanalytical chemistry》2010,396(8):2909-2919
We introduce a simplified sample preparation method using bare TiO2 nanoparticles (NPs) to serve as multifunctional nanoprobes (desalting, accelerating, and affinity probes) for effective enrichment
of phosphopeptides from microwave-assisted tryptic digestion of phosphoproteins (α-casein, β-casein and milk) in Electrospray
Ionization Mass Spectrometry (ESI-MS) and Matrix Assisted Laser Desorption Ionization Mass Spectrometry (MALDI-MS). The results
demonstrate that TiO2 NPs can effectively enrich and accelerate the digestion reactions of phosphoproteins in aqueous solutions and also from complex
real samples. After the microwave experiments, we directly injected the resulting solutions into the ESI-MS and MALDI-MS systems
for analysis, and excellent sensitivity was achieved without the need for any washing procedure or separation process. The
reasons are attributed to the high binding affinity and selectivity of TiO2 NPs toward phosphopeptides. Thus, phosphopeptides can be adsorbed onto the TiO2 NP surface. The digested or partially digested phosphoproteins can be concentrated onto the TiO2 NP surface. This results in the effective or complete digestion of phosphoproteins in a short period of time (45 s). In addition,
high sensitivity and sequence coverage of phosphopeptide can be obtained using TiO2 NPs as microwave absorbers and affinity probes in MALDI-MS and ESI-MS. This is due to the photocatalytic nature of the TiO2 NPs because the absorption of microwave radiation that can accelerate the activation of trypsin for efficient digestion of
phosphoproteins and enhances the ionization of phosphopeptides. The lowest concentrations detected for ESI-MS and MALDI-MS
were 0.1 μM and 10 fmol, respectively, for α-casein. Comparing the two-step approach of TiO2 NPs with microscale TiO2 particles, the microscale TiO2 particles shows no effect on the microwave-assisted tryptic digestion of phosphoproteins. The current approach offers multiple
advantages, such as great simplicity, high sensitivity and selectivity, straightforward and separation/washing-free technique
for phosphorpeptide enrichment analysis. 相似文献
108.
Zafar A. Siddiqi M. Shahid Mohd Khalid Shabana Noor Sarvendra Kumar 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2010,75(1):61-68
The newly prepared homo-bimetallic complexes [M2(imda)2(H2O)4], [M2(imda)2(Bipy)2] (M = Co, Ni or Cu) and [Fe2(imda)2(H2O)3Cl] (H2imda = iminodiacetic acid and Bipy = 2,2′-bipyridine) have been studied employing IR, FAB-mass, 1H and 13C NMR, EPR and ligand field spectra, which indicated a high-spin state of metal ion with hexa-coordinate environment. 57Fe Mössbauer data of the homo-bimetallic complex [Fe2(imda)2(H2O)3Cl] confirm a high-spin configuration with Fe (±3/2 → 1/2) nuclear transitions and the presence of Kramer's double degeneracy. At RT, the spin–spin interactions of the neighbouring nuclei (Fe3+–Fe3+ = S5/2–S5/2) are anti-ferromagnetically coupled. However, at LNT, the complex acquires a mixed-valent [FeIII–FeII] composition corroborated from the X-band EPR data. CV studies indicated the presence of quasi-reversible redox CuII/I, CuII/III, FeIII/II, FeIII/I and FeII/I couples. 相似文献
109.
Zafar A. Siddiqi Mohd Khalid Sarvendra Kumar M. Shahid Shabana Noor 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2010,75(2):841-845
Spectral and molecular model computations on homo-dinuclear complexes [M2L2(H2O)2Cl2] [L = 1-(salicylaldeneamino)-3-hydroxypropane, M = Cr3+, Mn3+, Fe3+, Co3+, Ni3+ or Cu3+] are consistent with a distorted hexa-coordinate geometry. X-band EPR spectral data indicated a rhombic distortion around Cu(II) ion. Magnetic moment and 57Fe Mössbauer data confirmed a high-spin state electronic configuration (t2g3eg2, S = 5/2) and asymmetric ligand environment around Fe(III) with nuclear transitions Fe(±3/2 → 1/2) exhibiting Kramer's double degeneracy. The neighboring Fe(III) nuclei in the homo-dinuclear species are antiferromagnetically coupled. 相似文献
110.
Hong Heng See Peter C. Hauser Wan Aini Wan Ibrahim Mohd Marsin Sanagi 《Electrophoresis》2010,31(3):575-582
Rapid and direct online preconcentration followed by CE with capacitively coupled contactless conductivity detection (CE‐C4D) is evaluated as a new approach for the determination of glyphosate, glufosinate (GLUF), and aminophosphonic acid (AMPA) in drinking water. Two online preconcentration techniques, namely large volume sample stacking without polarity switching and field‐enhanced sample injection, coupled with CE‐C4D were successfully developed and optimized. Under optimized conditions, LODs in the range of 0.01–0.1 μM (1.7–11.1 μg/L) and sensitivity enhancements of 48‐ to 53‐fold were achieved with the large volume sample stacking‐CE‐C4D method. By performing the field‐enhanced sample injection‐CE‐C4D procedure, excellent LODs down to 0.0005–0.02 μM (0.1–2.2 μg/L) as well as sensitivity enhancements of up to 245‐ to 1002‐fold were obtained. Both techniques showed satisfactory reproducibility with RSDs of peak height of better than 10%. The newly established approaches were successfully applied to the analysis of glyphosate, glufosinate, and aminophosphonic acid in spiked tap drinking water. 相似文献