量子点被广泛应用于生命科学研究中的多个领域。由于含有镉（Cd）元素，其生物学毒性效应及其对环境、健康的影响成为新的研究热点。量子点降解或团聚与其潜在毒性密切相关，但适合复杂样本的分离分析方法目前尚无研究。本项目组在前期工作基础上，运用电泳技术鉴定和分离纳米颗粒这一新思路，将抗干扰能力强、高分辨并且环保的毛细管电泳（CE）分离技术与超灵敏的电感耦合等离子体/质谱（ICP-MS）检测技术联机，建立适合水体样本、细胞培养液和生物样本的灵敏准确的量子点及其降解与团聚物的CE-ICP/MS分析方法，并对其进行方法效能指标的评价。基于CE-ICP/MS分析方法，结合MTT、SCGE等实验，研究量子点在不同反应体系中降解与团聚的变化规律；分析量子点降解与团聚物的含量及存在形式与细胞毒性的关系，以及对生物蓄积、排泄和靶器官生理功能的影响，旨在为量子点的分析检测和毒性研究提供新的方法和关键技术支撑。

Quantum dots (QDs) are widely used in the fields of life science research. Because they are cadmium-containing materials, evaluation of their biological toxicity， effects on the environment and human health are of increasing concerns.Our project team have identified various patterns of the elements composition of QDs in animal organs, which demonstrate that QDs have been part of the degradation and/or aggregation in vivo. It had been proven that the degradation and/or aggregation contribute to the overall toxicity of QDs.However, up to now, there has been few study on the analysis methods of QDs' degradation and/or aggregation in complex samples. We noticed that capillary electrophoresis (CE) offers higher separation efficiency with strong anti-interference ability and requires much smaller volume of sample. We also noticed that inductively coupled plasma mass spectrometry (ICP-MS) is a highly sensitive method for detecting metallic elements, for the detection limit for 111Cd can even approach to 0.1 ppb (ng/ml).Based on our latest study and the two notions above, this project would (1) use the new idea of electrophoresis technology for nanoparticles' separation and purification, coupling CE with ICP-MS to develop a method of capillary electrophoresis-inductively coupled plasma mass spectrometry ( CE-ICP/MS)for the detection of QDs' degradation and/or aggregation in water ,cell culture medium and biological samples, (2) evaluate the method of CE-ICP/MS,(3)using CE-ICP/MS, study on the change laws of QDs'degradation and/or aggregation in various system, and explore the relationship between the contents and patterns of QDs'degradation and/or aggregation with cytotoxicity,biological accumulation, excretion and physiological function, combined with MTT，SCGE and many other analysis methods. Our project aims for providing pivotal method and technology for the analysis and toxicity studies of QDs.