Babica Pavel, Kohoutek Jirí, Bláha Ludek, Adamovský Ondrej, Marsálek Blahoslav
Centre for Cyanobacteria and Their Toxins, Institute of Botany, Academy of Sciences of the Czech Republic & RECETOX, Masaryk University, Kamenice 126/3, 62500, Brno, Czech Republic.
Anal Bioanal Chem. 2006 Aug;385(8):1545-51. doi: 10.1007/s00216-006-0545-8. Epub 2006 Jul 8.
The efficiencies of conventional extraction techniques and analytical methods (HPLC-DAD and ELISA) were investigated for analyses of microcystins (MCs) in sediments. Our results showed several limitations. First, the extraction efficiency strongly depends on the extraction solvent, and extraction with 5% acetic acid in 0.2% trifluoroacetic acid (TFA)-methanol was confirmed as being the most appropriate for three different sediments (recovery: 33.1-44.9% of total MCs according to HPLC analyses). Second, the recovery of MCs was affected by the type of sediment but did not clearly correlate with the content of organic carbon. These results suggest that the sorption of MCs onto inorganic materials such as clay minerals is probably a more important process than interactions of the MCs with organic sediment matter. Third, the structure of the MCs is another crucial factor that affects the sorption of MCs and their recovery from sediments. Hydrophilic MC-RR gave much lower recoveries (20.0-38.8%) than MC-YR (44.1-59.5%) or MC-LR (55.3-77.8%) from three different types of spiked sediments. Recovery results analysed with HPLC-DAD correlated well with ELISA analyses. Further, extraction with 5% acetic acid in 0.2% TFA-methanol was used for analyses of MCs in 34 natural sediment samples collected from Brno reservoir (Czech Republic) from April to October 2005. Concentrations of MCs in sediments ranged from 0.003 to 0.380 microg/g sediment d.m. (ELISA results) or 0.016-0.474 microg/g d.m. (HPLC results). These values are equivalent to 0.63-96.47 microg/L of sediment (ELISA) or 4.67-108.68 microg/L (HPLC), respectively. Concentrations of sediment MCs showed both temporal and spatial variability, with the highest MC contents observed in the spring (April and May) and the lowest concentrations in July and August. Our results demonstrate the suitability of the methods described here for studying the occurrence, fate and ecological role of MCs in the aquatic environment.
研究了常规提取技术和分析方法（高效液相色谱-二极管阵列检测法和酶联免疫吸附测定法）用于分析沉积物中微囊藻毒素（MCs）的效率。我们的结果显示了几个局限性。首先，提取效率强烈依赖于提取溶剂，经证实，用0.2%三氟乙酸（TFA）-甲醇中的5%乙酸进行提取最适合三种不同的沉积物（根据高效液相色谱分析，总MCs的回收率为33.1-44.9%）。其次，MCs的回收率受沉积物类型的影响，但与有机碳含量没有明显的相关性。这些结果表明，MCs吸附到无机材料如粘土矿物上可能是比MCs与有机沉积物之间的相互作用更重要的过程。第三，MCs的结构是影响MCs吸附及其从沉积物中回收率的另一个关键因素。从三种不同类型的加标沉积物中，亲水的MC-RR的回收率（20.0-38.8%）远低于MC-YR（44.1-59.5%）或MC-LR（55.3-77.8%）。高效液相色谱-二极管阵列检测法分析的回收率结果与酶联免疫吸附测定法分析结果相关性良好。此外，用0.2% TFA-甲醇中的5%乙酸进行提取，用于分析2005年4月至10月从布尔诺水库（捷克共和国）采集的34个天然沉积物样品中的MCs。沉积物中MCs的浓度范围为每克沉积物干重0.003至0.380微克（酶联免疫吸附测定法结果）或0.016-0.474微克/克干重（高效液相色谱结果）。这些值分别相当于每升沉积物0.63-96.47微克（酶联免疫吸附测定法）或4.67-108.68微克/升（高效液相色谱）。沉积物中MCs浓度呈现出时间和空间变异性，春季（4月和5月）MC含量最高，7月和8月浓度最低。我们的结果证明了这里描述方法适用于研究MCs在水生环境中的发生、归宿和生态作用。
