ИСТИНА

Detonation nanodiamonds (DND) have a wide scope of application due to their noticeable mechanical and optical properties and their interaction with biological units[1]. Hybrid carbon materials such as detonation nanodiamonds-carbon nanotubes (DND@CNT) are of great scientific interest because they possess unique properties of both allotropic modifications of carbon. The main purpose of this part of work is to study the influence of modification of nanodiamonds by carbon nanotubes on Myramistin adsorption. In this work, the DNDs investigated were obtained from Technolog (Saint-Petersburg) and hybrid material DND@CNT. Primary particle size was established by Transition electron microscopy (TEM). DND and DND@CNT aqueous suspensions were prepared. By means of Dynamic light scattering (DLS) and capillary electrophoresis in pH range 3 to 12 we found out that the samples under investigation possessed an isoelectric point at 10 and 9 for DND and DND@CNT, respectively. Electrokinetic potential values in aqueous media were 27 mV for both samples. Adsorpiton of benzyldimethyl[3-(myristoylamino)propil]ammonium chloride nonohydrate (Myramistin) as a surfactant was studied in aqueous media. The adsorption experiment was carried out at Myramistin concentrations range 0,02 to 5,8 mmol/l. Tritium labeled Myramistin was obtained by tritium thermal activation technique and was used for adsorption study. The labeled Myramistin solution was added to DNDs suspension and was thermostated at 25°С, then the DNDs was decanted by centrifugation, and supernatant radioactivity was measured to establish the equilibrial Myramistin concentration in it, then the DNDs were washed, and their radioactivity was measured to establish Myramstin adsorption on them. It was found out in the research that myramistin adsorption at the concentrations range studied may be described by an equation analogous to Langmuir equation. Samples of DNDs with adsorbed myramistin were described by Fourier transform infrared spectroscopy. FTIR spectra of DND with myramistin showed no distinction to initial DND. Earlier, the same result was revealed for DND produced by Synta (Belarus). On the contrary, FTIR-spectra of DND@CNT with myramistin contained more distinct bands at 2930, 2856, 1653 and 1540 cm-1 which corresponded to myramistin. To conclude, in this research work we have shown that hybrid material DND@CNT possess bigger adsorption capacity on such a surfactant as myramistin than unmodified DND. Also, higher suspension stability of both DND samples with adsorbed myramistin has been revealed. The work was carried out with financial support of RFFR. (grant №17-03-00985).