In the work, the possibility of using nanoparticles of gold (AuNPs) to upgrade bioselective elements of biosensors in order to improve their analytical characteristics is considered. The bioselective elements of biosensors based on acetylcholinesterase (AChE), butyryl cholinesterase (BuChE) and glucose oxidase (GOD) were used as an experimental model. Immobilization of enzymes on the surfaces of conductometric transducers was performed by the crosslinking of corresponding enzymes using glutaraldehyde. The conditions of immobilization of AChE with gold nanoparticles were optimized. Thus, we determined the optimal values of concentration of crosslinking agent (glutaraldehyde), duration of immobilization, the enzyme to AuNPs ratio, the AuNPs concentration and size. The performance characteristics of the biosensors based on enzymes and AuNPs were investigated and compared with the characteristics of biosensors based on enzymes only. It was also examined how the addition of AuNPs to the bioselective element of biosensors affects the biosensor stability. In particular, the reproducibility of preparation and continuous operation of biosensors was tested as well as their stability at storage. It was shown that the presence of AuNPs in the composition of bioselective elements can improve some characteristics of biosensors, which may be promising for further study and use.

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In this paper, we present the results of a study of the properties of silver and copper nanoparticle (NP) ensembles and Fe3O4:Gd:B composites, which are promising for their potential uses in biomedicine. Magnetic resonance is applied as the main method of analysis. The magnetic properties of the NPs are found to be highly sensitive to the nanoparticle size, which enables finding the size distributions of metal NPs, using magnetic measurements. The dependence of the magnetic properties of lyophilized ensembles of Ag and Cu NPs on the interaction with molecular oxygen is revealed. The composites magnetic system Fe3O4:Gd:B is a key component of a promising method for neutron-capture therapy. The magnetic properties of this system, which are the result of differences in the g-factors of its components, are described in detail. As a consequence, the dependence of the resulting g-factor on the ratio of the components is established.

In dentistry and surgery a special role belongs to medications of the local action that possess the antimicrobial and anti-inflammatory properties and can stimulate the tissue regeneration.Aim. To study the antimicrobial activity of colloidal solutions of silver and gold nanoparticles in vitro, estimate their pharmacological activity in vivo and substantiate the composition and technology of 3 dosage forms based on thema hydrophilic ointment, gel and solution for wound cleansing.Materials and methods. Colloidal solutions of spherical silver and gold nanoparticles with the particle size of 30 nm and the concentration of 8.0 mg/ml and 77.2 μg/ml nanoparticles, respectively, were used to develop dosage forms. The antimicrobial activity of colloidal solutions of silver and gold nanoparticles was determined using the test strains of Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Bacillus subtilis, Enterococcus faecalis, Candida albicans, Proteus vulgaris, as well as clinical isolates of pathogenic strains of microorganisms isolated from patients with purulent inflammatory diseases of the maxillofacial area. The therapeutic efficacy of colloidal solutions of silver and gold nanoparticles in vivo was studied on the model of the jaw abscess of the experimental animals (Wistar rats). Technological methods were used to make dosage forms in accordance with the general rules for the manufacture of liquid and semi-solid medicines.Results and discussion. It has been found that silver nanoparticles in the concentration of 0.16 mg/ml and their combination with gold nanoparticles in the concentration of 0.08 mg/ml for Ag and 1.93 μg/ml for Au exhibit a high level of the antimicrobial activity against all test microorganisms. Gold nanoparticles as independent antimicrobial agents within the concentration range of 1.93-38.6 μg/ml exhibit a weak antimicrobial activity. The combination of silver nanoparticles with gold nanoparticles exhibit the marked anti-inflammatory action and contribute to decontamination and healing of the wound in the studies in vivo compared to the effect of silver nanoparticles only. The studies conducted made it possible to substantiate the choice of the concentration of colloidal solutions in dosage forms.Conclusions. According to the results obtained the marked complex action (antimicrobial, anti-inflammatory, regenerative) of the сombination of colloidal solutions of silver and gold nanoparticles in the treatment of purulent-inflammatory diseases of the maxillofacial area has been determined. The composition and technology of 3 dosage forms based on them -an ointment, gel, solution for wound cleansing, which can be promising for application in dentistry and surgery, have been substantiated. Дослідження з фармацевтичної розробки лікарських форм з наночастинками срібла і золота для застосування у стоматології і хірургіїУ стоматології і хірургії особлива роль належить засобам місцевої дії, які володіють антимікробними та протизапальними властивостями, а також здатні стимулювати процеси репа...

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