Safety assessment and biochemical evaluation of the effect of biogenic silver nanoparticles (using bark extract of C. zeylanicum) on Rattus norvegicus rats

Abstract

Background: Biosynthesized silver nanoparticles (AgNPs) are widely used in various biomedical applications. However, limited reports are currently available about the safety of biofabricated AgNPs using Cinnamomum zeylanicum bark extracts. Objectives: The current study is aimed to assess the potential toxicity of biosynthesized AgNPs (using C. zeylanicum) by subacute oral administration in experimental rats. Methods: AgNPs were biofabricated using methanol extract of C. zeylanicum bark and characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Twenty-four Rattus norvegicus female rats were divided into 4 groups (6 animals per group) as follows: Group-I was the control, while groups II, III, and IV were given 0.85, 1.76 and 3.53 mg/kg doses of AgNPs, respectively for 14 consecutive days. After 14 days of oral administration of AgNPs, serum levels of malondialdehyde (MDA), superoxide dismutase (SOD) and catalase (CAT) were measured using an ELISA technique. Serum concentrations of urea, creatinine, aspartate transaminase (AST) and alanine transaminase (ALT) were also determined as well as histopathologic features of the liver and the kidney. Results: AgNPs did not induce any changes in mean body weight, biochemical parameters (AST, ALT, urea and creatinine), oxidative stress biomarkers (MDA, SOD and CAT) and histopathologic features (of the liver and kidneys) of the treated groups when compared to control group. Conclusions: Our findings suggest that the oral administration of biogenic AgNPs (biofabricated using methanol extract of C. zeylanicum) to rats at a specific dose is relatively safe and does not show any signs of toxicity.