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Liquid chromatography-electrospray ionisation mass spectrometry was evaluated in the high-throughput analysis of microcystins and nodularins, cyanobacterial peptide hepatotoxins. Extracts originating from cyanobacterial strains and field material were separated on a 30 mm × 4 mm I.D. Merck Purospher STAR RP-18e column using a rapid gradient of aqueous formic acid and acetonitrile, ionised by electrospray technique and analysed on a Micromass Quattro II triple-quadrupole mass spectrometer operated in the selected ion recording (SIR) mode. The total analysis time per sample was 2.8 min corresponding to 514 samples a day. The system showed good robustness during a series of 320 repetitive injections of a field sample containing three major microcystins. 相似文献
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Summary A new method for the determination of microcystins PR and LR in cyanobacterium was developed using cyano-type prepacked cartridges. The microcystins were extracted with 10% acetic acid and the extract applied to a Baker 10 cyano cartridge. After elution from the cartridge with 0.5M acetic acid-acetonitrile (19) the microcystins were determined by HPLC. Better recoveries and chromatograms were observed than with ODS cartridges. 相似文献
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Analysis of cyanobacterial toxins by hydrophilic interaction liquid chromatography-mass spectrometry 总被引:5,自引:0,他引:5
The combination of hydrophilic interaction liquid chromatography with electrospray mass spectrometry (HILIC-MS) has been investigated as a tool for the analysis of assorted toxins produced by cyanobacteria. Toxins examined included saxitoxin and its various analogues (1-18), anatoxin-a (ATX-a, 19), cylindrospermopsin (CYN, 20), deoxycylindrospermopsin (doCYN, 21), and microcystins-LR (22) and -RR (23). The saxitoxins could be unequivocally detected in one isocratic analysis using a TSK gel Amide-80 column eluted with 65% B, where eluent A is water and B is a 95% acetonitrile/water solution, both containing 2.0 mM ammonium formate and 3.6 mM formic acid. The analysis of ATX-a, CYN and doCYN required 75% B isocratic. Simultaneous determination of 1-21 was also possible by using gradient elution. HILIC proved to be suitable for the analysis of microcystins, but peak shape was not symmetric and it was concluded that these compounds are best analysed using existing reversed-phase methods. The HILIC-MS method was applied to the analysis of field and cultured samples of Anabaena circinalis and Cylindrospermopsis raciborskii. In general, the method proved quite robust with similar results obtained in two different laboratories using different instrumentation. 相似文献
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Shan Y Shi X Dou A Zou C He H Yang Q Zhao S Lu X Xu G 《Journal of chromatography. A》2011,1218(13):1743-1748
Microcystins and nodularins are cyclic peptide hepatotoxins and tumour promoters from cyanobacteria. The present study describes the development, validation and practical application of a fully automated analytical method based on on-line micro solid-phase extraction-capillary liquid chromatography-tandem mass spectrometry for the simultaneous determination of seven microcystins and nodularin-R in tap water and lake water. Aliquots of just 100 μL of water samples are sufficient for the detection and quantification of all eight toxins. Selected reaction monitoring was used to obtain the highest sensitivity. Good linear calibrations were obtained for microcystins (50-2000ng/L) and nodularin-R (25-1000 ng/L) in spiked tap water and lake water samples. Excellent interday and intraday repeatability were achieved for eight toxins with relative standard deviation less than 15.7% in three different concentrations. Acceptable recoveries were achieved in the three concentrations with both tap water matrix and lake water matrix and no significant matrix effect was found in tap water and lake water except for microcystin-RR. The limits of detection (signal to noise ratio=3) of toxins were lower than 56.6 ng/L which is far below the 1 μg/L defined by the World Health Organization provisional guideline for microcystin-LR. Finally, this method was successfully applied to lake water samples from Tai lake and proved to be useful for water quality monitoring. 相似文献
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Marek Trojanowicz 《Journal of separation science》2010,33(3):359-371
Microcystins are cyclic peptide hepatotoxins that are produced during blooming of cyanobacteria. In recent two decades they gained a great interest because of the related ecological and public health risks. Over 70 different analogs of microcystins have been isolated from natural blooms and laboratory cultures of cyanobacteria. Because they are inhibitors of protein phosphatases they act as tumor promoters, but on the other hand, inhibitive enzymatic and ELISA methods may be employed for their screening or quantitative determination. Much larger analytical potential for this purpose have, however high‐performance separation chromatographic and electromigration techniques. Based on about 70 references from original journal papers these methods are reviewed together with presentation of their preconcentration methods and clean‐up procedures for analyzing environmental samples. Some attention is also focused on increasing application of LC/MS methods, and comparison of separation techniques with immunochemical or enzymatic methods. 相似文献
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Microcystins, cyclic heptapeptidic hepatotoxins produced by a number of bloom forming freshwater cyanobacteria, are considered to represent a serious risk to public health through drinking and recreational water. A highly sensitive bioassay relying on the specific inhibition of the human protein phosphatase 2A was applied to the quantification of microcystins. A systematic approach based on the rational testing of seven purified mcyst variants as well as characterized environmental samples allowed to point out the limits and experimental bias associated with this assay. All the seven microcystin variants known as microcystins RR, YR, LR, LY, LA, LW and LF strongly inhibited the enzyme with IC50 ranging between 0.29±0.02 and 0.84±0.07 nM for microcystins LW and YR, respectively. Using the model system of Microcystis aeruginosa PCC7820 axenic cultures and within the 1-year study of a Planktothrix agardhii bloom, the PP2A assay was shown to be strongly correlated to high-performance liquid chromatography (HPLC) coupled to ultra violet diode array detection. However the slope of the linear regression was significantly influenced by the sample composition, as confirmed by HPLC coupled to electrospray ionization mass spectrometry. A model based on pure additivity of mcyst effects was established to describe PP2A inhibition by standard mcyst mixtures, and fully agreed with experimental observations. 相似文献
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Electrochemical detection of microcystins, cyanobacterial peptide hepatotoxins, following high-performance liquid chromatography 总被引:1,自引:0,他引:1
Jussi Meriluoto Brendan Kincaid Malcolm R. Smyth Mikael Wasberg 《Journal of chromatography. A》1998,810(1-2):226-230
A novel amperometric HPLC detection method for the cyanobacterial (blue–green algal) peptide toxins microcystin-LR, -YR and -RR was developed. Purified microcystins and cyanobacterial extracts were chromatographed using an internal surface reversed-phase column with acetate- and phosphate-based mobile phase systems. Electrochemical oxidation reactions at 1.20 V vs. Ag/AgCl (glassy carbon working electrode) were shown to originate in arginine and tyrosine residues of microcystins. 相似文献
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直接进样-高效液相色谱-串联质谱法测定地表水中9种微囊藻毒素 总被引:2,自引:0,他引:2
建立水样直接进样-高效液相色谱-串联质谱分析地表水中9种微囊藻毒素(MCs)的方法.水样过滤后注入高效液相色谱,在电喷雾离子源正离子多反应模式下进行检测.对色谱及质谱条件进行优化,对过滤滤膜进行筛选,并采用本方法测定了实际样品.研究表明,地表水中9种MCs的浓度与峰面积呈良好的线性关系,回收率92.4%~100.1%,相对标准偏差均<7%.方法的检出限为0.007~0.047 μg/L,能够满足WHO及我国地表水中关于微囊藻毒素控制标准的要求.本方法灵敏、快速,适于地表水中9种MCs的测定. 相似文献