The rapid development of medicine has forced equally rapid progress in the field of pharmaceuticals. In connection with the expensive and time-consuming process of finding new drugs, great emphasis is put on the design and use of metal and metal oxides nanoparticles in nanomedicine. The main focus is on comprehensive presentation of both physicochemical properties and the possibilities of using, in particular, silver (Ag) and gold (Au) nanoparticles, as well as zinc oxide (ZnO) and titanium oxide (TiO₂) nanoparticles as drug carriers and in the treatment of cancer. An important element of this subject is the possibility of occurrence of toxic effects of these nanoparticles. For this reason, possible mechanisms of toxic actions are presented, as well as methods used to reduce their toxicity to ensure the safety of drug carriers based on these nanostructures.

The rapid development of the production of materials containing metal nanoparticles and metal oxides is a potential risk to the environment. The degree of exposure of organisms to nanoparticles increases from year to year, and its effects are not fully known. This is due to the fact that the range of nanoparticle interactions on cells, tissues and the environment requires careful analysis. It is necessary to develop methods for testing the properties of nanomaterials and the mechanisms of their impact on individual cells as well as on entire organisms. The particular need to raise public awareness of the main sources of exposure to nanoparticles should also be highlighted. This paper presents the main sources and possible routes of exposure to metal nanoparticles and metal oxides. Key elements of research on the impact of nanoparticles on organisms, that is, in vitro tests, in vivo tests and methods of detection of nanoparticles in organisms, are presented.

A series of poly(vinyl alcohol) (PVA) based liquid compositions with addition of zinc oxide, silver and copper nanoparticles has been prepared. The compositions also contained other consistency-forming organic components. The physico-chemical properties of the products have been determined. Their pH and density have been assessed. Also, the size of nanoparticles has been defined with using a dynamic light scattering technique. The compositions were subjected to XRD, FT-IR and microscopic analysis as well. Thanks to the incorporation of both metal oxide and metallic nanoparticles, it was possible to enrich the products with antibacterial properties. Their inhibiting properties in the growth of microorganisms have been confirmed against both Gram-negative and Gram-positive strains such as E. coli, S. aureus and P. aeruginosa. Thanks to the ability for solidification, the compositions may be applied on a bacterially contaminated surface, and after destroying the microorganisms and its solidification, it may be peeled off along with the dead bacterial film.