The science that involves nano-sized particles have been shown to have a huge impact on a variety of research fields, such as electronics, medicine, engineering, robotics and technology. The involvement of biological agents in nanoscience helped in the origin of bionanotechnology, which is deeply rooted in therapeutic and medical applications. This review provides an initiative to understand the combination of biological molecules and nanoparticles in delivering a great impression in the world of therapeutics.Conjugation of nanoparticles with the biological molecules makes them more friendly for the living system by increasing biocompatibility and reducing toxicity.Growing research in this area has revealed the identification and characterization of numerous biological agents of nano-sized that can serve as better carrier systems. They are exploited in the development of advanced nanoparticle-based targeted drug delivery systems. In general, either the combined form or the one in the derived form of nanoparticles from different biological organisms provides a valuable understanding of their specifications and importance in different therapeutic aspects.The combined form of biological molecules and nanoparticles is not yet well understood, and this might provide a baseline for prospects.This review provides an understanding of biologically synthesized and conjugated nanoparticles and their potential as therapeutic norms and highlights their applications, especially in the clinical field.

Recently, there has been an upsurge among people around the world in maintaining a sustainable and hygienic environment. This is due to the over-exploitation of recourses causing environmental pollution and spreading bacterial infections. In this regard, scientists are motivated to develop smart coatings where environmental pollutants and bacterial cells are degraded when in contact with their surfaces.In our previous report, ZnO nanoparticles (NPs) were prepared using the precipitation technique, showing good photocatalytic and antibacterial activity [1]. In this context, the present study details the use of ZnO NPs as pigment for the fabrication of alkyd resin-based self-cleaning coating. The coating was developed by mixing ZnO NPs and alkyd resin along with the additives using the ball milling technique. The developed coating was characterized using field emission scanning electron microscopy, energy dispersive X-ray spectroscopy, atomic force microscopy, and water contact angle measurements.To elucidate the self-cleaning and hygienic behaviour of the ZnO/alkyd resin coating, the dried coating was exposed to crystal violet (CV) solution as a model dye pollutant and bacterial strains to assess its photocatalytic and antibacterial activity. The droplets of CV solution placed over the coating almost degraded after 360 min of exposure to sunlight owing to the presence of ZnO NPs in the coating. Further, the coating exhibits reasonable antibacterial activity against E. coli and P. aeruginosa whereas it displays low antibacterial activity against S. aureus.Even though, the self-cleaning coating shows promising results, tuning the activity of the photo-catalytic pigment can improve the pollutant degradation efficiency and elevate bactericidal activity.ZnO NPs-impregnated alkyd resin coating for self-cleaning applications is novel.