Journal: Environmental Science & Technology
Article Title: Quantitative Assessment of Particulate Matter Biodistribution Using 14 C‑Nanotracing and Accelerator Mass Spectrometry
doi: 10.1021/acs.est.5c11834
Figure Lengend Snippet: Schematic overview of the 14 C-nanotracing strategy and labeling process for particulate matter (PM). (A) Schematic representation of the 14 C-nanotracing workflow for PM. 14 C-labeled PM is generated through pyrolysis of 14 C-labeled hydrocarbons. The resulting PM is oxidized to CO 2 using a sample oxidizer and captured in a scintillation cocktail for quantification via liquid scintillation counting (LSC). The labeled PM is administered to mice under defined exposure conditions, after which organs are harvested and pretreated for radiocarbon analysis. LSC is employed for samples with high 14 C activity, while AMS is used for samples with low radioactivity. (B) Schematic of the PM labeling process via 14 C-incorporated pyrolysis. 14 C-labeled n -hexane (“hot”) is blended with unlabeled n -hexane (“cold”) to achieve the desired 14 C concentration. The mixture is introduced into a pyrolysis system, where thermal decomposition generates reactive radicals and small hydrocarbon fragments. These intermediates undergo recombination to form graphitization precursors, leading to carbonaceous PM formation. During this process, 14 C atoms are randomly incorporated into the carbon matrix, resulting in uniformly 14 C-labeled PM.
Article Snippet: Homogenates were digested using Solvable (6NE9100, PerkinElmer, USA) according to the manufacturer’s instructions, mixed with liquid scintillation cocktail, and analyzed over 2 h periods using a LSC system (TRI-CARB 4810TR, PerkinElmer, USA).
Techniques: Labeling, Generated, Pyrolysis, Activity Assay, Radioactivity, Concentration Assay