Narayanan Santhanam1, Aravind Arivazhagan1, Krithiga Mohan Kennedy2, Subhashini Swaminathan1*
1Department of Biotechnology, SRM Institute of Science and Technology, Chennai, Tamil Nadu, India.
2College of Pharmacy, SRM Institute of Science and Technology, Chennai, Tamil Nadu, India.
*Address for Correspondence
Department of Biotechnology, SRM Institute of Science and Technology, Chennai, Tamil Nadu, India
Objective: The purpose of this study is to synthesize silver nanoparticles using Aloe barbadensis leaf extract by green chemistry approach and to determine the anti-cancer activity of synthesized silver nanoparticles on THP-1 acute monocytic leukemia cells. Material and methods: The Aloe barbadensis leaf was analysed for its phytoconstituents using biochemical test which revealed presence of many important phytocompounds. The nanoparticles were then synthesized using leaf extract and characterized by UV-vis spectroscopy, FTIR, XRD, zeta potential, FESEM and EDX which revealed that nanoparticles possess FCC structure with size ranging from 6 nm to 24 nm. Results and conclusion: The in-vitro antileukemic activity was determined by MTT assay on THP-1 cell lines which showed significant cell death in concentration dependent manner. The DAPI staining and arcidine orange/ethidium bromide dual staining showed apoptotic nuclei in silver nanoparticles treated cells. The Annexin V FITC/PI analysis using flow cytometry showed increase in apoptotic cell population in concentration dependent manner and cell cycle analysis showed cell cycle arrest at Sub G0/G1 phase. DCFDA dye staining revealed increase in intracellular ROS followed by rhodamine 123/PI staining which revealed depolarization of mitochondria. The caspase 3 level was upregulated indicating that the synthesized silver nanoparticles induce caspase 3 mediated apoptosis in THP-1 cells in-vitro and caspase 3 activity was confirmed by DNA fragmentation ladder assay which showed fragmentation of DNA.Our results show that green synthesis of silver nanoparticles synthesized using Aloe barbadensis leaf extract is eco-friendly, cost efficient, convenient and inhibited the proliferation of THP-1 leukemia cells indicating the potential use of Aloe barbadensis mediated silver nanoparticles has potential to develop as nano drug for leukemia therapy.
Keywords: Silver nanoparticles, green synthesis, Aloe vera, leukemia, anticancer, apoptosis, flow cytometry, biomedical application, nanomedicine