Abstract

One of the major challenges in metal ecotoxicology is to identify the sites and forms of metal bindings which are subsequently linked with the metal functions such as bioavailability, trophic transfer, bioaccumulation, and toxicity. Over the past decades, there had been numerous efforts to tease out the metal speciation and binding strategies with further identification of their biological significance. Bioimaging by directly visualizing the metal distribution in different biological systems (cells, tissues or whole individuals) has emerged as a new tool in metal ecotoxicological studies. This review examines the various modern technologies for nanoscale (subcellular) or macroscale (tissues or individuals) imaging of metals in aquatic organisms, including autoradiography, mass spectrometry (laser ablation inductively coupled plasma mass spectrometry, nano-secondary ion mass spectrometry), X-ray fluorescence, and fluorescent bioprobes. Some of the techniques are more advanced and sophisticated than the others, and each of them has its own advantages and disadvantages. Currently, there are very few studies which attempted to link the metal imaging with functionality. With the advent of modern sophisticated technology, it is clear that bioimaging will become an important tool in metal toxicological studies and reveal many mechanisms underlying metal transport in biological systems with their potential implications for metal toxicity. Other technology needs to be further supplemented for metals, especially by coupling with speciation analysis. One exciting potential is to study the cellular (or organismic) responses to different metals by combining different bioimaging technologies. While bioimaging is mainly qualitative in nature, quantitative assessment should be further explored.

摘要

金属生态毒理学的主要挑战之一是确定金属结合的位点和形式，这些位点和形式随后与金属功能有关，如生物利用度、营养转移、生物积累和毒性。在过去的几十年里，人们进行了许多努力来梳理金属形态和结合策略，并进一步确定它们的生物学意义。通过直接可视化不同生物系统（细胞、组织或整个个体）中的金属分布进行生物成像已成为金属生态毒理学研究的新工具。本综述探讨了各种现代技术，用于对水生生物中的金属进行纳米级（亚细胞）或宏观（组织或个体）成像，包括放射自显影，质谱（激光烧蚀电感耦合等离子体质谱、纳米二次离子质谱）、X 射线荧光和荧光生物探针。其中一些技术比其他技术更先进和复杂，并且每种技术都有其自身的优点和缺点。目前，很少有研究试图将金属成像与功能联系起来。随着现代尖端技术的出现，很明显，生物成像将成为金属毒理学研究的重要工具，并揭示生物系统中金属转运的许多机制及其对金属毒性的潜在影响。其他技术需要进一步补充金属，特别是与形态分析相结合。一个令人兴奋的潜力是通过结合不同的生物成像技术来研究细胞（或有机体）对不同金属的反应。虽然生物成像本质上主要是定性的，但应进一步探索定量评估。