离子强度对苝与溶解有机质疏水性组分相互作用的影响  

Effects of Ion Strength on Interaction Between Perylene and Hydrophobic Fractions of Dissolved Matter(DOM) Isolated from Lake Water

作　　者：梅毅[1] 王立英[1] 

机构地区：[1]中国科学院地球化学研究所环境地球化学国家重点实验室,贵州贵阳550081

出　　处：《矿物学报》2016年第2期295-300,共6页Acta Mineralogica Sinica

基　　金：国家自然科学基金项目(批准号:41173128;41273148)

摘　　要：自然界水体(如地下水、湖泊、河流及海洋)中的溶解有机质(DOM)因具有显著的生态及环境功能而受到人们的广泛关注:DOM能够影响环境中污染物的命运,比如疏水性有机污染物(HOCs)与天然有机质结合后,其迁移途径、生物可利用性和毒性受到明显的控制,其对环境中生物的危害性减弱。本文运用荧光猝灭法测定了多环芳烃苝(perylene)与提取自红枫湖天然水体的DOM有机组分,计算了苝与DOM有机组分相互作用的分配系数(KDOC),探讨了影响相互作用的因素以及水体离子强度对分配系数的影响。研究认为,红枫湖DOM有机组分对多环芳烃苝的吸附能力与其芳香结构单元有很强的相关性,log KDOC值与有机组分在280 nm处的摩尔吸收(ε280)和分子质量有线性度较高的正比关系。一般而言,离子强度对分配系数的影响比较复杂,就总体趋势而言,增加离子强度有利于对PAHs吸附能力的提高。Dissolved organic matter（DOM） in nature waters（e.g. ground water, lake, river and ocean） receives much attention because of its remarkable ecology and the environment function. More importantly, DOM can affect the fate of the contaminants in environment. For instance, interactions between contaminants and DOM can change their transport, toxicity and bioavailability, attenuating their harm for organisms. In this work, we fractionated large amounts of lake water into hydrophobic DOM-fractions and determined the partitioning coefficients（KDOC） of perylene binding to DOM-fractions by florescence quenching titration. Effect of ion strengthens of the solutions on KDOC of perylene was also examined. Results show that KDOCvalues of perylene was positive correlated with molecular weights and UV absorbance at 280 nm（ε280） and KDOC increased with increasing ion strengthens, suggesting that the binding is controlled by hydrophobic interactions.

关 键 词：溶解有机质 有机组分 疏水性有机污染物 荧光猝灭法 离子强度 

分 类 号：X142[环境科学与工程—环境科学]