LVEM helps study bioaccumulation of nanoparticles in marine environments
Particles in our oceans
The concern over micro-sized and nano-sized particles in our oceans continues to gain public and research interest. Initial attention has focused on the impact of plastic materials in marine environments, including their potential to degrade into nanoparticle size pieces of plastic. Single use plastic, including food wrappers, has become the largest source of pollution recovered on recent beach cleanup efforts globally.
Yet forward-looking scientists are also concerned about the potential risks posed by more advanced materials that are making their way into society, including carbon nanotubes (CNTs). A recent article by researchers at Université du Québec à Rimouski focused on studying whether CNTs have the potential to bioaccumulate in fish (Soubaneh, 2020). This study involved using radioactively labeled carbon-14 [14C] to create functionalized CNTs ([14C]-f-CNTs) as tracers for uptake in fish, here juvenile Arctic char (Salvelinus alpinus). These tracer functionalized CNTs are relevant because materials scientists often modify CNTs to increase their water solubility or enhance other properties. This creates a greater potential for the nanomaterials to interact with aquatic environments should they ultimately end up there.
Characterizing tracer CNTs
Soubaneh and colleagues purchased commercially available CNT feedstocks, and performed these common processing techniques to impart the functionality and tracer label. This required detailed characterization of the materials before their use in the aquatic studies, and the opportunity for the LVEM5 to shine as a powerful tool for characterizing nanomaterials.
LVEM5 TEM images of tracer functionalized carbon nanotubes used for bioaccumulation studies (Adapted from Soubaneh, 2020).
Using whole body autoradiography to measure the bioaccumulation and distribution of the CNTs in the fish revealed build up in the head of the fish, which the authors attributed to the entry of the CNTs via pores in the bone canals and subsequent interactions with bone materials.
Soubaneh YD, Pelletier E, Desbiens I, Rouleau C. Radiolabeling of amide functionalized multi-walled carbon nanotubes for bioaccumulation study in fish bone using whole-body autoradiography. Environmental Science and Pollution Research. 2020 Feb;27(4):3756-67.
About the author:
Robert I. MacCuspie, Ph.D., has over twenty years of experience in nanotechnology and materials characterization, at national laboratories, academia and corporations, working at the interface of business and science.