Subacute Toxicological Profile Assessment of Silver-Nanoparticles After Topical Mucosal Application in Albino Rats

Aim:The present study aimed to assess the toxicity of topical administration of two concentrations of silver nanoparticles after 28 days exposure. Materials and Methods:Sixty males albino rats were randomly divided into the following experimental groups; Group 1 (vehicle control group): consisted of 20 healthy rats (given 0.5 ml distilled water once daily for 4 weeks topically on ratʼs tongue).Group 2:(nano-silver 50 group): consisted of 20 healthy rats (given 0.5 ml nanosilver solution50 μg/ml once daily for 4 weeks topically on ratʼs tongue in a dose of 10mg/kg).Group 3 (nano-silver 100 group): consisted of 20 healthy rats (given 0.5 ml nanosilver solution100 μg/ ml once daily for 4 weeks topically on ratʼs tongue in a dose of 10mg/kg).By the end of study blood was drawn then analyzed for GOT (glutamic oxaloacetic transaminase), GPT (glutamic pyruvic transminase), CRE (creatinine), and BUN (blood urea nitrogen).Tongue, kidneys, and liver were removed, weighed, fixed, stained, and examined under light microscopy for histopathological study. Results:The results showed that there was no significant difference in the organs weight of rats after 4 weeks of exposure, no significant changes in all four enzymes tested.Histopathologic examination revealed no pathological abnormalities in all treated animals compared to untreated healthy animals.(no inflammatory cell infiltration, no hyperplasia, no fatty degeneration ,no edema ,as well as no necrosis). Conclusion:silver nanoparticle (size 20 nm) in concentrations of 50,100 μg/ml in dosing volume 10mg/kg body weight are safe when applied topically in rats for 28 days.