海洋贝类对纳米银的吸收及其生物效应

Though nanosilver has been widely used in electronic devices, medicine, food, textile, personal care products and environmental remediation applications due to its antibacterial activity, its biological effects to marine organisms and potential ecotoxicity to marine environments are far below well-known. In this study we will use the radiotracer methodology and DGT (Diffusive Gradients in Thin-films) technique to quantify the uptake and bioaccumulation of nanosiver in model biomonitors, the marine bivalves Perna viridis and Ruditapes philippinarum. The defense (metallothionein and glutathione S-transferase) and damage (lactate dehydrogenase and acetylcholinesterase) biomarkers will be examined to explore the nanosiver toxic mechanism in marine bivalves. The post-exposure behavior, being more ecological concerning biomarkers compared to the physio-biochemical markers, will also be studied to investigate the potential ecological effects of nanomaterials. The study will elucidate more on the toxicity and environmental effects of nanomaterials, thus help the sustainable development of nanomaterials and nanotechnologies.

纳米银已广泛应用于电子、医药、食品、纺织、个人护理及水处理等行业，但是其对海洋生物的毒性效应以及潜在的生态危害远不为我们所知。本课题采用同位素示踪手段及薄层扩散梯度技术（Diffusive Gradients in thin-films Technique）研究海洋贝类对纳米银的吸收蓄积；以防御性生化标志物（金属硫蛋白含量及谷胱甘肽-S-转移酶活性）和损伤性生化标志物（乳酸脱氢酶及乙酰胆碱酯酶活性）通过体内研究（in vivo）探讨纳米银对海洋贝类生物防御机制的诱导及机体损伤效应，解析纳米银的致毒机理；同时以个体水平的行为效应（post-exposure behaviroral markers）研究纳米金属胁迫效应的累积而导致的更高水平的生物损害，了解纳米银与离子态银生物效应的异同，为评估海洋环境中纳米金属的潜在生态危害、完善纳米材料环境影响的监管机制及可持续地发展纳米科技提供科学依据。

纳米银在电子、医药、食品、纺织、个人护理及水处理等行业的广泛应用，使得研究其对海洋生物的毒性效应以及潜在的生态危害成为国际热点。本课题以青岛经济贝类菲律宾蛤仔Ruditapes philippinarum为主要模型生物，研究了海洋贝类对纳米银的吸收蓄积，并以防御性生化标志物（金属硫蛋白含量及谷胱甘肽-S-转移酶活性、过氧化氢酶）和损伤性生化标志物为观察体系，通过体内研究（in vivo）探讨了纳米银对海洋贝类生物防御机制的诱导及机体损伤效应，表面了纳米可累本身及其释放的自由离子是两种可能的致毒机理；同时以个体水平的行为效应（post-exposure behaviroral markers）研究了纳米金属胁迫效应的累积而导致的更高水平的生物损害，对比研究了纳米银与离子态银对海洋生物的毒害效应。本研究的结果为全面并正确评估纳米金属在海洋环境中潜在的生态危害、完善纳米材料环境影响的监管机制及可持续地发展纳米科技提供科学依据。环境理化条件也对纳米生物效应有很大影响。