Novelty of the investigation. The study of nanoparticles' bactericidal properties and laser radiation antimicrobial activity is quite relevant for experimental substantiation of laser nanotechnologies' application efficiency. Application of laser and nanotechnologies is considered to be one of the most current and promising trends in modern experimental medicine.

The aim of the investigation was to study the markedness of copper nanoparticles' and low-intensity laser radiation (LILR) antimicrobial action and to evaluate the effectiveness of their combined application in in vitro experiment.

The aim of the study was to develop the method of infected skin burn wound modelling and to substantiate experimentally the effectiveness of copper nanoparticles' and low-intensity laser radiation (LILR) combined application in the treatment of infected burn wounds of the skin.

Materials and methods. Markedness of synthesized copper nanoparticles' and laser radiation antimicrobial effect on Pseudomonas aeruginosa and Staphylococcus aureus was evaluated according to MacFarland by mixing daily cultures. In the first series of the experiments the culture of the microorganisms was subjected to radiation for two minutes using the ALT "Matrix" apparatus; in the second series copper nanopowder suspension was introduced into the culture of the microorganisms; in the third series laser radiation and introduction of copper nanoparticles were combined. On the basis of the experiment on 50 white laboratory rats of 190-200g. weight there was developed and patented the method of skin burn wound simulation; the effect of copper nanoparticles' and low-intensity laser radiation combined application in the treatment of infected burn wounds was studied in the experiment on 50 similar animals.

Results. Low antibacterial LILR activity was noted; reliable decrease of the number of colonies was observed at nanocopper introduction. There was revealed reliable synergism of antimicrobial action of copper nanoparticles' and LILR combined application. Using the developed laser radiation method, skin burns of controlled damage depth and area were modelled. Peculiarities of the simulated wound process development in skin burn wound infection, markedness of antibacterial effect of various copper nanoparticles' concentrations and laser radiation parameters were detected. Combined local application of LILR and copper nanoparticles in experimental animals of the group under observation provided by the 7^th day of treatment discontinuation of pathogenic microflora inoculation, by the 4^th day - appearance of granulations, and by the 14^th day of treatment-wound epithelization.  

Conclusion. Combined application of LILR and copper nanoparticles allows to obtain antibacterial effect at lower concentrations of copper nanoparticles, thus decreasing possible toxic action of the given substance on the organism in in vivo conditions. The obtained findings of experimental studies with the use of planimetric and microbiological methods of investigation suggest rather high efficiency of combined application of copper nanoparticles and laser radiation, the effect surpassing that of standard methods of treatment in duration and adequacy of wound epithelization.