邻苯二甲酸二甲酯在离体人红细胞内的分布和含量研究

邻苯二甲酸酯类污染物(PAEs)在环境中普遍存在,可沿食物链富集,危害人体健康。本文利用荧光光谱法和高效液相色谱法(HPLC)探究了邻苯二甲酸二甲酯(DMP)在离体人红细胞内的分布情况。结果表明,红细胞在310 nm、490 nm和609nm处各具有一个荧光特征峰,其来源分别为:红细胞内的蛋白;还原型烟酰胺腺嘌呤二核苷酸磷酸(NADPH)、黄素腺嘌呤二核苷酸(FAD)和膜脂;锌卟啉和原卟啉。DMP染毒后,310 nm处的荧光峰出现明显下降,其原因为进入红细胞内的DMP与蛋白发生了结合;490 nm和609 nm处的荧光峰变化很小。高效液相色谱(HPLC)实验结果表明,DMP能透过红细胞膜进入细胞内部,其进入量随暴露量增加而增加,进入量和暴露量的比值随暴露量增加而减少。上述研究成果能加深对PAEs在血液运输过程中与红细胞毒性作用的理解,可为PAEs的危险性评估和相关疾病预防提供数据参考。

Distribution and Level of Dimethyl Phthalate in Erythrocytes in Vitro

Phthalate esters (PAEs) is widely present in the environment. It poses a threat to human health through accumulation in the food chain. The distribution of a typical PAEs, i.e., dimethyl phthalate (DMP), in human erythrocytes in vitro was explored by using fluorescence spectroscopy and HPLC. The experimental results indicated that the fluorescence spectrum of erythrocytes have three fluorescence peaks, successively located at 310 nm, 490 nm and 609 nm, which are caused by the protein in erythrocytes; nicotinamide adenine dinucleotide phosphate (NADPH), flavin adenine dinucleotide (FAD) and membrane lipid; zinc porphyrin and porphyrin, respectively. After exposure to DMP, the intensity of the fluorescence peak at 310 nm significantly decreased due to the binding of DMP with the protein in erythrocytes, while no significant change in the intensity of the fluorescence peaks at 490 nm and 609 nm was observed. The experimental results of HPLC indicated that DMP could pass through the cell membrane and enter the cell. The DMP level in the cell increased with the increasing exposure level. The ratio of the DMP level in the cell to the exposure level decreased with increasing exposure level. The results will shed light on the understanding of the cytotoxicity of PAEs in the process of blood transport.