The convenient synthetic strategy for the one-pot synthesis of silver nanoparticles capped by tartaric acid with a controlled size is reported here. Their characterization is revealed through spectroscopic protocols, such as UV/Vis and FTIR, while SEM, DLS and a Zetasizer revealed the surface morphology, size distribution and surface charge on the nanoparticles. The surface plasmon resonance (SPR) band was observed at 406 nm with 1.07 a.u absorbance, the image for SEM shows that the particles were monodispersed and spherical in shape, while the z-average size distribution of AgNPs/TA in a colloidal solution was found to be 79.20 nm and the surface charge was monitored as −28.2 mV. The antibacterial activities of these capped nanoparticles alone and in synergism with selected fluoroquinolones (ofloxacin, sparfloxacin, ciprofloxacin and gemifloxacin) and macrolides (erythromycin and azithromycin) were assessed on selected Gram-negative as well as Gram-positive organisms by employing the disc diffusion method. Antioxidant activity against the DPPH (1,1-diphenyl-2-picrylhydrazyl) was also evaluated using the standard assay method. The antibacterial activity of the antibiotics has been increased against studied microorganisms, showing the positive synergistic effect of the capped nanoparticles. A potential therapeutic application of AgNPs/TA in combination with antibiotics is determined from the results of the present research. These capped nanoparticles also possess good antioxidant activity and, therefore, can be used in various fields of biomedical sciences.

The impact of computer-aided drug designing in the field of medicinal chemistry has created a boon in the drug discovery process. Molecular docking is an integral part of bioinformatics that deals with protein-ligand interactions, binding conformations, and affinity predictions. It has shown to be a rapid, easy, and affordable method in business and research settings alike. The advancement in the hardware and software has led to enhanced molecular dynamic simulations and thus authenticate the computational results. This has created a great impact in minimizing the cost and time involved in the drug discovery process. It has also helped in identifying the rationale for drug repurposing approaches. This chapter will give in-depth knowledge of the importance of molecular docking in drug designing and discovery, their impact on drug repurposing, and success stories of the in silico approach in drug discovery and repurposing.