Quantification of particulate Ag in rainbow trout organs following dietary exposure to silver nitrate, or two forms of engineered silver nanoparticles

Abstract

Following exposure to a diet containing a control (no added Ag), AgNO3, Ag NPs or Ag2S NPs, Ag-containing particles were found in organs of all treatments, with the highest concentrations following exposure to AgNO3 or Ag NP.

Uptake and depuration of Ag nanoparticles versus Ag ions by zebrafish through dietary exposure: characterization of Ag nanoparticle formation and dissolution in vivo and toxicokinetic modeling

“…26 The identity of the biogenic Ag particles was predicted using Visual MINTEQ with the results showing that the reaction of Ag + with gut fluid Cl − formed fairly insoluble AgCl (s) particles. 26 Our data show for the first time (Fig. 3 and S7 †) that the biogenic Ag nanoparticles resulting from dietary Ag + exposure to zebrafish were zerovalent Ag, Ag 2 S, and/or their composite nanoparticles.…”

“…The biogenic Ag particles formed in the fish treated with dietary Ag + were first reported in a very recent study on the dietary uptake of Ag + by juvenile rainbow trout. 26 The identity of the biogenic Ag particles was predicted using Visual MINTEQ with the results showing that the reaction of Ag + with gut fluid Cl − formed fairly insoluble AgCl (s) particles. 26 Our data show for the first time (Fig.…”

“…1a–d), in contrast to the strong formation of biogenic particles with levels comparable to that of the dietary AgNP uptake in the earlier work. 26 One possible reason for this difference might be the varied fish species used. No prior study has shown Ag 2 S nanoparticle or AgNP formation in fish upon exposure to Ag + .…”

“…23,24 Recent studies have employed the spICP-MS method to show that the form of Ag uptaken by rainbow trout following the dietary AgNP exposure remained as a particulate form, and that even dietary exposure to Ag + resulted in the biogenic Ag particle accumulation in vivo. 25,26 The identity of the biogenic Ag particles formed was predicted to be insoluble AgCl (s) resulted from the reaction of Ag + with the gut fluid Cl − ions. 26 It is noted that the spICP-MS method has some limitations, as it does not directly analyze the speciation of particles and that the accurate sizing actually requires prior knowledge of the particle composition.…”

“…25,26 The identity of the biogenic Ag particles formed was predicted to be insoluble AgCl (s) resulted from the reaction of Ag + with the gut fluid Cl − ions. 26 It is noted that the spICP-MS method has some limitations, as it does not directly analyze the speciation of particles and that the accurate sizing actually requires prior knowledge of the particle composition. 27,28 Thus, complementary methods are necessary to achieve a clearer picture of the nature and biological fate of Ag particles bioaccumulated in biota.…”