Department of Environmental Engineering, Technical University of Denmark, Building 113, DK-2800 Kgs. Lyngby, Denmark.
Nanotoxicology. 2013 Sep;7(6):1082-94. doi: 10.3109/17435390.2012.710657. Epub 2012 Aug 16.
Aquatic toxicology of engineered nanoparticles is challenged by methodological difficulties stemming partly from highly dynamic and poorly understood behavior of nanoparticles in biological test systems. In this paper scientific and technical challenges of testing not readily soluble nanoparticles in standardised algal growth inhibition tests are highlighted with specific focus on biomass quantification methods. This is illustrated through tests with TiO2 and Au nanoparticles, for which cell-nanoparticle interactions and behavior was studied during incubation. Au NP coating layers changed over time and TiO2 nanoparticle aggregation/agglomeration increased as a function of concentration. Three biomass surrogate measuring techniques were evaluated (coulter counting, cell counting in haemocytometer, and fluorescence of pigment extracts) and out of these the fluorometric methods was found to be most suitable. Background correction was identified as a key issue for biomass quantification, complicated by algae-particle interactions and nanoparticle transformation. Optimisation of the method is needed to reduce further particle interference on measurements.
由于纳米颗粒在生物测试系统中的高度动态和理解不足的行为，工程纳米颗粒的水生毒理学受到方法学困难的挑战。本文重点介绍了在标准化藻类生长抑制测试中测试不易溶解的纳米颗粒的科学和技术挑战，特别关注生物量定量方法。通过对 TiO2 和 Au 纳米颗粒的测试说明了这一点，在孵育过程中研究了细胞-纳米颗粒相互作用和行为。Au NP 涂层随时间变化，TiO2 纳米颗粒的聚集/团聚随着浓度的增加而增加。评估了三种生物量替代测量技术（库尔特计数、血球计数器中的细胞计数和色素提取物的荧光），其中荧光法被认为是最适合的方法。背景校正被确定为生物量定量的关键问题，这是由藻类-颗粒相互作用和纳米颗粒转化引起的。需要对该方法进行优化，以进一步减少颗粒对测量的干扰。
