Potential of DNA silver nanoparticles for in-vitro antibacterial and anticancer activity

DNA nanoparticles are considered as smart revolution in nanotechnology field which are multifunctional structures with purine -pyrimidine base combination applied widely in drug delivery and therapeutics owing to the augmented properties and synergistic combination of DNA with silver. Green synthesis of silver nanoparticles is an effective, ecofriendly, non toxic method. (Allium cepa, Lilliaceae) well known for anticancer and other pharmacological activities, was selected as candidate drug to isolate DNA. The objective of the work was to synthesize DNA silver nanoparticles and study its in-vitro antibacterial and anticancer activities. The DNA was isolated by salting out method using methylated spirit, salt and detergent and characterized by UV, NMR and mass spectroscopy (MASS) which confirmed the presence of nucleotide bases. Silver nanoparticles were synthesized by green method using DNA as complexing agent. The DNA silver nanoparticles were characterized (UV, dynamic light scattering (DLS), fourier transform infrared spectroscopy (FTIR), X- Ray diffraction studies (XRD) and scanning electron microscopy (SEM)) determined the particles size as 153 +/- 2.4 nm, no signs of agglomeration, faced centered cubic structure and good stability. In-vitro antibacterial activity performed by agar well diffusion method against Gram positive Streptococcus aureus and Gram-negative Escherichia coli proved that DNA silver nanoparticles have broad spectrum activity compared to DNA. The cytotoxic potential was tested by MTT assay on human skin cancer melanoma cell line G361 using doxorubicin as standard and the DNA silver nanoparticles was cytotoxic to cancer cells. Future research interests towards in-vivo anticancer activity may show promising results for application in drug therapeutics.