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BACKGROUND: Graphene layers are potential candidates in a large number of applications due to their novel properties. However, little is known about their behaviors and associated potential risks largely as a result of a lack of quantification techniques in complex environmental matrices. OBJECTIVES: Radioactively labeled graphene was synthesized and used to evaluate its uptake, depuration, and maternal transfer in Daphnia magna. METHODS: Graphene was synthesized by means of graphitization and exfoliation of sandwich-like FePO4/dodecylamine hybrid nanosheets, and 14C was incorporated in the synthesis. 14C-labeled graphene was spiked to artificial fresh water and the uptake and depuration of graphene were assessed by aquatic organism Daphnia magna. Gravid Daphnia were used to assess maternal transfer of graphene. RESULTS: After exposure for 24 h to a 250 µg L-1 solution of graphene, the graphene concentration in the organism was nearly 1% of the organism dry mass. These organisms were able to excrete the graphene to clean artificial freshwater and achieve roughly constant body burdens after 24 h depuration periods regardless of the initial graphene exposure concentration. Addition of algae and humic acid (HA) to the water during the depuration period resulted in release of a significant fraction (90%) of the accumulated graphene, but some still remained in the organism. TEM of the graphene excreted by Daphnia suggest that they dramatically impact the physical properties of graphene. Accumulated graphene in maternal Daphnia was likely inherited by the neonates. CONCLUSIONS: 14C-labeled graphene a) was able to overcome significant previous limitations for their quantification in environmental and biological media; b) may be accumulated in maternal Daphnia and inherited by the neonates; and c) was accumulated up to nearly 1% of the organism dry mass but was eliminated in the presence of algae.
Guo, X.
, Dong, S.
, Petersen, E.
, Gao, S.
, Huang, Q.
, Gu, C.
and Mao, L.
(2013),
Biological Uptake and Depuration of Radio-labeled Graphene by Daphnia magna, Environmental Health Perspectives, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=914056
(Accessed October 14, 2025)