ИСТИНА

Detonation nanodiamonds (DND) are a promising platform for drug delivery with controlled release. Developed surface of nanodiamonds provides high adsorption capacity and possibility of formation of stable adsorption complexes with drugs including antibiotics. The example of such complex that was previously obtained and well described is nanodiamond-myramistin composite. Being surface active compound myramistin can form adsorption complexes with both positively and negatively charged nanodiamonds. When nanodiamond is proposed as a drug delivery platform or as a covering material for biological tissues, it’s biocompatibility is critically important. To provide biocompatibility to nanodiamond-antibiotic composite coating with biological material is considered as a perspective tool. Hyaluronic acid is a promising material in this capacity. Nanodiamond produced by PlasmaChem (Germany) as a powder as well as a suspension were used to prepare nanodiamond-myramistin-hyaluronic acid complexes. To reveal a direct amount of both myramistin and hyaluronic acid in the complex, tritium labeled compounds were used. Tritium label was included either in drug or in biopolymer, so the amount of labeled compound can be determined by means of liquid scintillation spectrometry on the background of non-labeled component. The following questions were considered: (1) how myramistin coverage influence on hyaluronic acid adsorption in wide range of biopolymer concentration; (2) how hyaluronic acid molecular weight influence on the adsorption, (3) how myramistin surface concentration influence the hyaluronic acid adsorption; and finally (4) how stable the adsorption complexes are in biological-alike media. Zeta potential of nanodiamond play a key role in the adsorption process that is under strong influence of the presence of drug. It was found that maximum adsorption of hyaluronic acid occurs, when zeta-potential is close to 20 mV, it can be reached either by application of initially positively charged nanodiamond or by adsorption of myramistin. Adsorption of hyaluronic acid on nanodiamonds converts zeta potential of positively charged nanodiamonds and does not influence on zeta potential of negatively charged nanodiamonds, but significantly adsorbes on its surface. Peculiarities of nanodiamon-myramistin-hyaluronic acid adsorption complexes formation will be described in the presentation.