Formulation and Evaluation of Albumin-Stabilized Silver Nanoparticles Loaded with Methotrexate: Anticancer Activity and DNA Binding Analysis with Molecular Modeling

Nano-metal technology has emerged recently as an exceptional biological targeted field with numerous advantages like small size and high surface charge. In this report, we described our research on the stabilization of prepared silver nanocores coated with bovine serum albumin and further loaded with methotrexate (MTX) drug. The prepared nanoparticles were characterized by using UV-Visible, X-ray diffraction (XRD), energy dispersive X-ray (EDX), scanning electron microscopy (SEM) and cyclic voltammetry (CV). The UV spectra of AgNP showed a prominent peak at 400 nm. The presence of MTX was confirmed by the FT-IR and EDX analysis. The AgNP-BSA-MTX particles resembled elliptical shape like structures in the SEM images. In-vitro drug release for free drug MTX occurred rapidly in a period of 12 hrs (85%), whereas a sustained release of MTX greater than 85% from the AgNP-BSA-MTX nanoparticles was observed for 48 hrs. The AgNP-BSA-MTX demonstrated a five-fold higher cytotoxic activity compared to free MTX drug alone against PC-3 cell lines, performed by the 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assay method. DNA binding studies were performed for the AgNP-BSA-MTX with calf thymus DNA (ct-DNA). In-silico studies were performed for MTX with DNA (Protein Data Bank ID-IZ3F) and a prominent interaction with the nucleotides was noted. Molecular Dynamics (MD) simulation studies were also performed for the docked MTX-DNA complex. The average of the Root mean square deviation (RMSD) values for the DNA backbone was calculated to be 5.71 +/- 0.48 nm.