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991.
Multi-residue analytical methods for the determination of pesticides and PPCPs in water by LC-MS/MS: a review 总被引:1,自引:0,他引:1
Ednei G. Primel Sergiane S. Caldas Ana L. V. Escarrone 《Central European Journal of Chemistry》2012,10(3):876-899
Residues of pesticides, pharmaceutical and personal care products (PPCPs) are contaminants of world-wide concern. Consequently,
there is a growing need to develop reliable analytical methods, which enable rapid, sensitive and selective determination
of these pollutants in environmental samples, at trace levels. In this paper, a review of the liquid chromatography-tandem
mass spectrometry (LC-MS/MS) based methods for the determination of pesticides and PPCPs in the environment is presented.
Advanced aspects of current LC-MS/MS methodology, including sample preparation and matrix effects, are discussed. 相似文献
992.
Hydrophilic interaction chromatography (HILIC) is an increasingly popular alternative to conventional HPLC for drug analysis.
It offers increased selectivity and sensitivity, and improved efficiency when quantifying drugs and related compounds in complex
matrices such as biological and environmental samples, pharmaceutical formulations, food, and animal feed. In this review
we summarize HILIC methods recently developed for drug analysis (2006–2011). In addition, a list of important applications
is provided, including experimental conditions and a brief summary of results. The references provide a comprehensive overview
of current HILIC applications in drug analysis.
相似文献
993.
Ana F. Kozmidis-Petrović 《Journal of Non》2012,358(9):1202-1209
Vogel–Fulcher–Tammann (VFT) equation and Mauro, Yue, Ellison, Gupta and Allan (MYEGA) equation for the viscous flow are here expressed using the parameters characteristic for Avramov and Milchev model. This enabled us to represent these functions through 3D diagrams and compare them directly. The 3D diagrams of these functions were compared as functions of the two variables for different temperature (or ratio T/Tr) and in a wide range of x. Tr is referential temperature at which ηTr = 1013 d Pa s.The 3D diagrams were also used to present the differences of these functions. It followed from the 3D diagrams that for x ~ 0.5 and x > 0.8 the most significant differences occur in the values of logη. For that reason equations are additionally tested on concrete silicate systems with such composition of x. The VFT and the MYEGA functions are then modified so that through Tr they include lubricant coefficient k. We show that the 3D diagrams of the so modified VFT and MYEGA functions can predict the behavior of viscosity of silicate systems, both when a component with large k and when a component with small k is present. With these some more frequent anomalies at certain parts of the 3D diagram were observed with the VFT function. The MYEGA function proved to be just as successful as the AM function in predicting the lubricant effect and showed good agreement with the experimental results. 相似文献
994.
A b-colouring of a graph is a colouring of its vertices such that every colour class contains a vertex that has a neighbour in all other classes. The b-chromatic number of a graph is the largest integer such that the graph has a -colouring with colours. We show here how to compute in polynomial time the -chromatic number of an outerplanar graph of girth at least . This generalizes the seminal result of Irving and Manlove on trees. 相似文献
995.
Cavalli S Carbajo D Acosta M Lope-Piedrafita S Candiota AP Arús C Royo M Albericio F 《Chemical communications (Cambridge, England)》2012,48(43):5322-5324
Aniline-catalyzed oxime chemistry was employed to conjugate a γ-amino-proline-derived cell penetrating peptide to superparamagnetic iron oxide nanoparticles (SPIONs). Internalization of the novel nanoconjugate into HeLa cells was found to be remarkably higher compared to the analogous TAT-SPION conjugate. 相似文献
996.
Noffke AL Habtemariam A Pizarro AM Sadler PJ 《Chemical communications (Cambridge, England)》2012,48(43):5219-5246
Bioorganometallic chemistry is a rapidly developing area of research. In recent years organometallic compounds have provided a rich platform for the design of effective catalysts, e.g. for olefin metathesis and transfer hydrogenation. Electronic and steric effects are used to control both the thermodynamics and kinetics of ligand substitution and redox reactions of metal ions, especially Ru(II). Can similar features be incorporated into the design of targeted organometallic drugs? Such complexes offer potential for novel mechanisms of drug action through incorporation of outer-sphere recognition of targets and controlled activation features based on ligand substitution as well as metal- and ligand-based redox processes. We focus here on η(6)-arene, η(5)-cyclopentadienyl sandwich and half-sandwich complexes of Fe(II), Ru(II), Os(II) and Ir(III) with promising activity towards cancer, malaria, and other conditions. 相似文献
997.
Barba-Bon A Costero AM Gil S Parra M Soto J Martínez-Máñez R Sancenón F 《Chemical communications (Cambridge, England)》2012,48(24):3000-3002
A new selective chromo-fluorogenic probe for Fe(3+), Cr(3+) and Al(3+) is reported. Detection limits are in the μM range and the fluorogenic sensing ability could be observed by the naked eye when illuminated with UV-light. No response is observed with divalent cations. 相似文献
998.
AM García-Deibe C Portela-García M Fondo AJ Mota J Sanmartín-Matalobos 《Chemical communications (Cambridge, England)》2012,48(79):9915-9917
A decanuclear Cd complex has been found as a carbonate-containing capsule. The structure strongly resembles a ten-blade waterwheel with a central carbonate ligand surrounded by two superimposed Cd(5)O(5) crowns with a pentagonal antiprism-like disposition. The capsule is doubly capped by two pentadentate perchlorate anions. 相似文献
999.
Antimicrobial and antioxidant activities of essential oils of Satureja thymbra growing wild in Libya
Giweli A Džamić AM Soković M Ristić MS Marin PD 《Molecules (Basel, Switzerland)》2012,17(5):4836-4850
The composition of essential oil isolated from Satureja thymbra, growing wild in Libya, was analyzed by GC and GC-MS. The essential oil was characterized by γ-terpinene (39.23%), thymol (25.16%), p-cymene (7.17%) and carvacrol (4.18%) as the major constituents. Antioxidant activity was analyzed using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging method. It possessed strong antioxidant activity (IC50 = 0.0967 mg/mL). The essential oil was also screened for its antimicrobial activity against eight bacterial and eight fungal species, showing excellent antimicrobial activity against the microorganisms used, in particular against the fungi. The oil of S. thymbra showed bacteriostatic activity at 0.001-0.1 mg/mL and was bactericidal at 0.002-0.2 mg/mL; fungistatic effects at 0.001-0.025 mg/mL and fungicidal effects at 0.001-0.1 mg/mL. The main constituents thymol, carvacrol and γ-terpinene also showed strong antimicrobial activity. The commercial fungicide bifonazole showed much lower antifungal activity than the tested oil. 相似文献
1000.
AM Rojas-Sepúlveda M Mendieta-Serrano MY Mojica E Salas-Vidal S Marquina ML Villarreal AM Puebla JI Delgado L Alvarez 《Molecules (Basel, Switzerland)》2012,17(8):9506-9519
The hydroalcoholic extract of the steam bark of B. fagaroides var. fagaroides displayed potent cytotoxic activity against four cancer cell lines, namely KB (ED50 = 9.6 × 10-2 μg/mL), PC-3 (ED50 = 2.5 × 10-1 μg/mL), MCF-7 (ED50 = 6.6 μg/mL), and HF-6 (ED50 = 7.1 × 10-3 μg/mL). This extract also showed anti-tumour activity when assayed on mice inoculated with L5178Y lymphoma cells. Bioactivity-directed isolation of this extract, afforded seven podophyllotoxin-type lignans identified as podophyllotoxin (1), β-peltatin-A-methylether (2), 5'-desmethoxy-β-peltatin-A-methylether (3), desmethoxy-yatein (4), desoxypodophyllotoxin (5), burseranin (6), and acetyl podophyllotoxin (7) by 1D and 2DNMR and FAB-MS analyses, and comparison with reported values. All the isolated compounds showed potent cytotoxic activity in the cell lines tested, especially compound 3, which exhibited greater activity than camptothecin and podophyllotoxin against PC-3 (ED50 = 1.0 × 10-5 μg/mL), and KB (ED50 = 1.0 × 10-5 μg/mL). This is the first report of the isolation of podophyllotoxin and its acetate in a Bursera species. 相似文献