Green synthesis of Aconitum violaceum-mediated Ag-ZnO nanocomposites and their potential biomedical applications

Abstract

Nanotechnology is one of the most promising technologies of the current era which gained a dynamic interest in the field of life sciences. Conventional approaches have been employed for nanoparticles synthesis, but they have many adverse effects. The utilization of medicinal plants for the production of nanoparticles have many benefits over other methods. Numerous bioactive compounds found in plants have the potential for the reduction and capping of nanoparticles. The purpose of this study was to synthesize silver-zinc nanocomposites (Ag-ZnO NCs) from roots, leaves and stem of Aconitum violaceum with their relevant extracts followed by characterization. The biosynthesized NCs were subjected to characterization using XRD, FTIR, SEM, EDX, DLS and HPLC. XRD pattern confirmed crystalline structure of NCs with average size of 62-72 nm. FTIR showed capping of NCs with phytochemicals present in root, leaf and stem of Aconitum violaceum, which acts as stabilizing and reducing agents in the synthesis of NCs. DLS was used to measure the zeta potential and particle size distribution. SEM demonstrated spherical structures either less or more clustered with some agglomerated particles. HPLC analysis was performed for both extract and Ag-ZnO NCs which revealed the presence of bioactive compounds (Benzoylmesaconine, Benzoylaconine, Benzoylhypaconine, Mesaconitine, Hypaconitine, Indaconitine, Aconitine). These biosynthesized NCs and their relative extracts demonstrated a broad spectrum of usages. Highest hemolytic activity (6.6 %) and brine shrimp lethality assay of Ag-ZnO NCs LC50 value (64.5±4.78 ug/ml) shows the toxicity of these nanocomposites. Anti-cancerous activities were tested using ROS/RNS, Caspase 3 gene expression, mitochondrial membrane potential and MTT assay. All the activities confirmed that Ag-ZnO NCs have high anticancer applications. This could be used for cancer therapy and drug delivery agents. Whole outcomes showed that the bio-fabricated Ag-ZnO NCs have vast in vitro biological and biomedical applications and could be utilized as a wide range agent for a wide range of biomedical applications. However, more investigations are required to explore and evaluate the therapeutic effects of Ag-ZnO NCs on animal models.