Volume 8, Issue 4 - Special Section: Nanomaterials for Medicine: Benefits and Risks

A series of finely dispersed Y 2 O 3 :Eu and YAG:Eu phosphors useful for the enhancement of photodynamic therapy (PDT) of cancer were prepared using the Pechini method and self-propagating high temperature synthesis (SHS). The obtained phosphors can be used in cancer therapy drugs in combination with a photosensitizer which accumulates selectively in tumor tissues. Upon excitation with X-ray irradiation which easily penetrates the organism such phosphors are activated to radiate the visible light with wavelengths required to stimulate the photosensitizer yielding active singlet oxygen which destroys cancer cells. Thus the developed phosphors provide an extension of PDT in the treatment of internal tumors which are inaccessible for activating light from the outside. A detailed characterization of the obtained phosphors was performed to define various types of adsorption centers and the functional groups on their surface, including hydroxyls with different acid-base characteristics and an admixture hydrated carbonate layer which may help in linking with other drugs (photosensitizer and pluronic binder) and is important in respect of biocompatibility. A model describing the composition of acid-base centers with various pK a values on the surface of the studied materials is suggested on the basis of the obtained results as an approach to study the adjustable modification of various compounds in respect of the compatibility between their ingredients as well as their overall biocompatibility. Y 2 O 3 :Eu phosphor prepared via the SHS method was successfully tested for biological (therapeutic) activity which provided an effective destruction of fibroblast cell cultures of Chinese hamster V-79 in combination with a photosensitizer upon X-ray irradiation.

Increased interest in nanosilver during the last 10 years is mainly explained by the emergence and spread of pathogenic microorganisms with multiple drug resistance, including resistance to last-generation antibiotics. In this article, we for the first time, give a description of large-scale clinical trials of a new nanosilver based antibacterial drug [containing two active components: silver nanoparticles (AgNPs) (10–50 ppm) and benzyldimethyl[3-(miristoylamino)-propyl]ammonium chloride (100 ppm)] registered in Russia in 2015 as a veterinary drug under the brand name Argumistin™. This drug has been approved for application in a diluted dosage form – as eye drops, intranasal drops and orally; it has also been approved for application in a more concentrated dosage form (up to 50 ppm of nanosilver) as ear drops and as an antiseptic during demodicosis and gum disease treatment, open wound treatment, etc. We have registered the high therapeutic effectiveness of Argumistin™ during treatment of infectious conjunctivitis, gingivitis, parodontosis and enteritis of dogs. Application of this antibacterial drug gives considerable (up to 70% in case of periodontal diseases) reduction in the treatment period and prevention of complications. The results of clinical trials in the treatment of infectious diseases of dogs makes Argumistin™ a promising candidate for an effective antibacterial drug for human medicine.

Currently, to provide complete information on measuring is one of the most essential problems for measuring devices. In order to obtain electrodes for recording of cardiac micropotentials in a wide range of frequencies, a process for modifying of the aluminum-silicon oxide ceramic matrix with bismuth or silver nanoparticles was investigated. It was found that when impregnating aluminum-silicon oxide ceramics with aqueous or organic solutions of the silver compounds with subsequent drying and calcinations, both the total amount of silver and its distribution over the thickness of the sample essentially depend on the nature of the silver precursor solution. Thus, when impregnating the aluminum-silicon oxide ceramics with an aqueous solution of silver nitrate followed by its reduction with formic acid, the silver content in the ceramic matrix does not exceed 15% and it is mainly distributed in the near-surface layer. The highest degree of impregnation (39%) and uniform distribution of silver throughout the volume of the sample are achieved by treatment of the ceramic matrix with a branched silver carboxylate (silver caprate) solution containing 250 g/L Ag, followed by drying and calcination of the samples at 250°C. It was shown that bismuth-containing electroconductive ceramics can be obtained by its impregnation with a solution of bismuth formate or caprylate followed by its calcination in vacuum at 280°C. The results of the study showed that the ceramic sensors modified with silver nanoparticles have a direct current drift of less than 5 nV/s while the noise level does not exceed±200 nV, which allows development of the measuring apparatus from 300 nV.

The growing production and use of nickel (Ni) nanopowders with low biopersistence makes dissolution and accumulation degree in a body an important parameters needed for the risk assessment of nanoparticles. We propose an experimental approach for rapid determination of the dissolution degree of nanoscale (77 nm) and ultrafine (275 nm) Ni particles in synthetic biological solutions. It has been shown that after 2 h of exposure to simulating saliva and lysosomal liquid the dissolution degree of nanoparticles can reach 30 and 60 wt.%, respectively. With decreasing of the particle’s size, they are characterized by increased solubility in saliva and the pulmonary tract; and the particles completely dissolve in 24 h. There was an attempt to predict the potential extent of accumulation of nickel compounds in the human body with particles entering the body by saliva or with breathing: with 3.8 times size decrease the probability of nickel accumulation in a body can rise in 3.5 times.

Bleomycin (BLM), a cytostatic drug widely used in the treatment of cancer, often induces lung fibrosis as a side effect. This phenomenon has been exploited in biomedical studies to create a fibrosis model. Inhalation of BLM nanoaerosol particles (NAPs) was expected to induce severe fibrosis in mice. Instead, inhalation of BLM NAPs for 13 days with a total inhaled dose of ~1 mg/kg did not cause pneumofibrosis in CD-1 mice; only marked pneumonitis with infiltration of macrophages in all parts of the lungs was observed in all eight mice exposed. These changes were notably reversible within 2 weeks of cessation of exposure. Despite the limited number of animals it was confidently concluded that slow administration of BLM in the form of NAPs did not cause fibrosis as the bolus instillation of similar doses does.

Potential human health and environmental risks associated with nanoscience research projects and their deliverables, termed nanosafety, is one of the important issues for translating research findings into commercially viable products. This paper examined the applicability of project management tools to address nanosafety in an efficient manner. Using objectives oriented project planning (OOPP) we describe a new integrated content of the problem tree, the result tree, and the logical framework approach (LFA), by modeling our nanomedicine research project entitled “Nanomedicine preparation based on antibody drug conjugate (ADC)” as a case study. As a main result of the case study, we demonstrated an LFA matrix that highlights the need to deal with nanosafety as an activity of the research project. Consequently, the activity can lead to the output, standing operating procedure (SOP), for managing the project waste disposals and its deliverables side effects. In general, such output can be concluded as an important output for all nanoscience research projects to avoid underestimating risks for their nano-objects. Moreover, this article is written in the hope of providing an easy-to-understand template of project management tools for novice nanomedicine researchers who aim to apply OOPP in the design of their research projects.

Lethal eye infections of newborns occur mostly due to their passage through the contaminated birth canal. In the pre-antibiotic era blindness from such infections was most challenging. This scenario changed after the 1880s with the use of Crede’s method (a drop of 2.0% silver nitrate solution into newborn’s eyes which was later reduced to 1.0%). This research is focused on finding the structure-function relationship between silver nitrate and tears which offer antimicrobial action. A reinvestigation of Crede’s method revealed a light-dependent instant formation of silver oxide nanoparticles (sizes 20–70 nm) with strong antimicrobial action against ocular pathogens. Nano-therapy would be the key reason behind the widely accepted use of silver nitrate eye drop as a prophylactic agent prior to the discovery of antibiotics. A scientific view on the age-old Crede’s method explores the use of nano-therapy as a prophylactic agent. When routine prophylaxis with topical antibiotics brings the risk of resistance, Crede’s method may, in the near future, offer a way to fight against ophthalmia neonatorum (ON) caused by antibiotic-resistant pathogens.