Abstract
The goal of the present study was to investigate the toxicity of biologically prepared small size of silver nanoparticles in human lung epithelial adenocarcinoma cells A549. Herein, we describe a facile method for the synthesis of silver nanoparticles by treating the supernatant from a culture of Escherichia coli with silver nitrate. The formation of silver nanoparticles was characterized using various analytical techniques. The results from UV-visible (UV-vis) spectroscopy and X-ray diffraction analysis show a characteristic strong resonance centered at 420 nm and a single crystalline nature, respectively. Fourier transform infrared spectroscopy confirmed the possible bio-molecules responsible for the reduction of silver from silver nitrate into nanoparticles. The particle size analyzer and transmission electron microscopy results suggest that silver nanoparticles are spherical in shape with an average diameter of 15 nm. The results derived from in vitro studies showed a concentration-dependent decrease in cell viability when A549 cells were exposed to silver nanoparticles. This decrease in cell viability corresponded to increased leakage of lactate dehydrogenase (LDH), increased intracellular reactive oxygen species generation (ROS), and decreased mitochondrial transmembrane potential (MTP). Furthermore, uptake and intracellular localization of silver nanoparticles were observed and were accompanied by accumulation of autophagosomes and autolysosomes in A549 cells. The results indicate that silver nanoparticles play a significant role in apoptosis. Interestingly, biologically synthesized silver nanoparticles showed more potent cytotoxicity at the concentrations tested compared to that shown by chemically synthesized silver nanoparticles. Therefore, our results demonstrated that human lung epithelial A549 cells could provide a valuable model to assess the cytotoxicity of silver nanoparticles.
Highlights
Silver nanoparticles (AgNPs) show much interest due to their unique physical, chemical, and biological properties [1]
The results suggested that bio-AgNPs at 25 μg/ml decreased the viability of A549 cells to 50% of the control level, so this was determined to be the IC50
This study was designed to evaluate the potential toxicity of bio-AgNPs in human lung epithelial adenocarcinoma cell line (A549)
Summary
Silver nanoparticles (AgNPs) show much interest due to their unique physical, chemical, and biological properties [1]. The use of AgNPs has become more widespread for sensing, catalysis, transport, and other applications in biological and medical sciences. This increased use has led to more direct and indirect exposure in humans [2,6]. It has been shown that small nanoparticles can translocate through and accumulate in an in vitro blood brain barrier model composed of rat brain microvessel vascular endothelial cells [10]. Trickler et al [11] demonstrated that small nanoparticles could induce inflammation and affect the integrity of a blood-brain barrier model composed of primary rat brain microvessel endothelial cells
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
