Katarzyna Mitura

Visualization of interaction between inorganic nanoparticles and bacteria or fungi

Purpose The objective of the present investigation was to evaluate the morphologic characteristics of self-assemblies of diamond (nano-D), silver (nano-Ag), gold (nano-Au), and platinum (nano-Pt) nanoparticles with Staphylococcus aureus (bacteria) and Candida albicans (fungi), to determine the possibility of constructing microorganism–nanoparticle vehicles. Methods Hydrocolloids of individual nanoparticles were added to suspensions of S. aureus and C. albicans. Immediately after mixing, the samples were inspected by transmission electron microscopy. Results Visualization of the morphologic interaction between the nanoparticles and microorganisms showed that nano-D, which are dielectrics and exhibit a positive zeta potential, were very different from the membrane potentials of microorganisms, and uniformly surrounded the microorganisms, without causing visible damage and destruction of cells. All metal nanoparticles with negative zeta potential had cell damaging properties. Nano-Ag showed the properties of self-organization with the cells, disintegrating the cell walls and cytoplasmic membranes, and releasing a substance (probably cytoplasm) outside the cell. Arrangement of nano-Au with microorganisms did not create a system of self-organization, but instead a “noncontact” interaction between the nanoparticles and microorganisms was observed to cause damage to fungal cells. Nano-Pt caused both microorganisms to release a substance outside the cell and disintegrated the cytoplasmic membrane and cell wall. Conclusion Nano-Ag, nano-Au, and nano-Pt (all metal nanoparticles) are harmful to bacteria and fungi. In contrast, nano-D bind closely to the surface of microorganisms without causing visible damage to cells, and demonstrating good self-assembling ability. The results indicate that both microorganisms could be used as potential carriers for nano-D.

Nanoparticles of carbon allotropes inhibit glioblastoma multiforme angiogenesis in ovo

The objective of the study was to determine the effect of carbon nanoparticles produced by different methods on the growth of brain tumor and the development of blood vessels. Glioblastoma multiforme cells were cultured on the chorioallantoic membrane of chicken embryo and after 7 days of incubation, were treated with carbon nanoparticles administered in ovo to the tumor. Both types of nanoparticles significantly decreased tumor mass and volume, and vessel area. Quantitative real-time polymerase chain reaction analysis showed downregulated fibroblast growth factor-2 and vascular endothelial growth factor expression at the messenger ribonucleic acid level. The present results demonstrate antiangiogenic activity of carbon nanoparticles, making them potential factors for anticancer therapy.

Nanocrystalline carbon coatings and powders for medicine

All the allotropic forms of carbon, i.e., diamond, graphite and carbine, find applications in different areas of medicine, but diamond is specifically preferred. The unique properties of thin diamond layers, due to the highest biocompatibility of carbon resulting from the presence of this element in human body, make them candidates for producing biomaterials. Especially carbon in the form of a nanocrystalline diamond film has found industrial applications in the area of medical implants. Diamond Powder Particles (DPP), as an extended surface NCD, are useful for medical examinations. Different medical implants are covered with Nanocrystalline Diamond Coatings (NCD). NCD forms a diffusion barrier between implant and human environment.

Bioactive food packaging with nanodiamond particles manufactured by detonation and plasma-chemical methods

Abstract Carbon-based materials are from principles compatible with living organisms. Newly invented nanodiamond-based materials are characterized by their resistance to radiation and have good biological tolerance for a number of systemic tissues. Most recently it has been found that nanodiamond particles have antioxidant, antiinflammatory, antiallergic, antibacterial, and antitumor properties. There are a number of research communications indicating that detonation nanodiamond particles are fairly reactive and that their surface can be effectively modified by chemical, mechanical, and plasma-chemical methods. Plasma-chemical modification of detonation nanodiamond particles gives the possibility to control the surface of nanodiamond particles in biological tests. Such nanoparticles, obtained by the detonation method, reveal the biological activity that is strongly depending on surface functionalization. The antioxidant and antibacterial properties of detonation nanodiamond particles can be used as an active packaging technology in the cosmetic and food industries. Newly invented food packaging layers containing nanodiamonds may exhibit improved durability, flexibility, as well as temperature and humidity resistance. Moreover, incorporation of functionalized nanodiamonds to the polymer matrix of food packaging layers may significantly change the oxygen-barrier and antimicrobial properties of new packaging materials. This chapter summarizes the recent advances on research and applications of diamonds and nanodiamonds particles in the food industry, medicine, and cosmetology. Moreover, potential toxicological risk of nanodiamonds modified food packaging layers is highlighted and discussed.

Biocompatibility and Toxicity of Allotropic Forms of Carbon in Food Packaging

Abstract It has currently been accepted that all allotropic forms of carbon are biocompatible with the living organism. Carbon nanoparticles reveal the unique biological activity depending on the presence of free bonds on the carbon surface. In the light of the present state of knowledge, the nanodiamond and graphene oxide nanoparticles have no significant toxic effect on animals. Biocompatibility of carbon nanoparticles is connected with the biodistribution of nanoparticles in internal organs, which was documented through in vivo examinations. It has been found that carbon nanoparticles (i.e., nanotubes and fullerenes) and nanodiamond particles have antimicrobial properties. Moreover, the new allotrope of carbon, graphene, revealed antibacterial activity. The interactions between bacterial cells and graphene materials depend on the site of interaction: its surface or edges. Foodborne bacterial pathogens, including Listeria monocytogenes, were located at the edges of a pristine graphene and a graphene oxide; however, when it comes to the graphene oxide, they adhered to the surface of the nanoparticle. The graphene oxide was found to have the highest antibacterial activity. Nowadays, the toxic effects of pristine graphene administered in ovo to chicken embryos were proved. Carbon nanotubes, graphene, and fullerenes, apart from silver originated nanoparticles, are the most common nanomaterials used in the cosmetics industry on packaging. It has been reported that different allotropic forms of carbon may cause the antibacterial effect, which is significant when packaging is in contact with food. The biocompatibility of carbon nanoparticles is an important element in the selection of food packaging. In this review, several aspects of biocompatibility and toxicity of allotropic forms of carbon in food packaging will be presented and discussed from a practical point of view.