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The possibility of applying silver, cadmium and zinc sulfide nanoparticles (npAg 2 S, npCdS and npZnS) obtained using Shewanella oneidensis MR-1 and Bacillus subtilis 168 bacterial cultures for the creation of a new class of polymeric bionanocomposite materials was investigated. Biogenic nanoparticles obtained in aqueous solutions of the corresponding salts in the presence of various types of microorganisms are characterized by the presence of protein molecules on their surface. The molecules composition is determined by the bacterial culture. Proteins stabilize them and allow the nanoparticles to covalently join the active groups of polymeric carriers. Aminated chloromethylated polystyrene microspheres, as well as ion-exchange resins of various types, were used as polymeric matrices. Analysis of interaction with them can be used as a method for studying the properties of biogenic nanoparticles of metal sulfides for subsequent successful selection of a polymeric carrier. The immobilization of biogenic nanoparticles of metal sulfides onto the surface of aminated chloromethylated polystyrene microspheres was found to depend on the level of stability of aqueous nanoparticle suspensions and is determined by the negative charge of biogenic npAg 2 S, npCdS and npZnS, which suggests covalent binding and the electrostatic interaction of the components in the composition of the polymer bionanocomposite. A comparative analysis of the parameters of nanoparticles depending on the strain used in the biosynthesis was carried out. Analysis of the main physicochemical characteristics of npCdS and npZnS showed that the small size of nanoparticles (npCdS-5 nm, npZnS-up to 2 nm) and the presence of luminescence peaks at wavelengths less than 400 nm classify them in the blue region of the fluorescence spectrum and identify them as quantum dots. Thus, the possibility of introducing fluorescent quantum dots of nanoparticles of metal sulfides of biogenic origin into various polymeric matrices has been demonstrated, which contributes to the expansion of the horizons for using a new class of nanoparticles to create polymeric bionanocomposites.

This work presents the results of a study of the resins of seven Ancient Egyptian mummies from the collection of the Pushkin State Museum of Fine Arts using a complex of analytical methods: gas chromatography, atomic emission and mass spectrometry. Natural bitumen and beeswax were identified in the resins using the gas chromatography–mass spectrometry method. Based on the results of hydrocarbon distribution in the profiles of n-alkanes in the resin coatings of the mummies and naturally occurring bitumen, it was assumed that the Dead Sea bitumen was used. The gas chromatography–mass spectrometry studies of mummy resins in the selected ion mode (m/z 217 and 191) provided additional evidence of the bitumen’s geographic origin. Atomic emission spectrometry with inductively coupled plasma was used as a means to determine the content of microelements. Vanadium, nickel and molybdenum were found in the tar of five mummies. The determined relative amounts of vanadium, nickel, and molybdenum in the resins of the studied mummies showed a good correlation with the available data on the content of these elements in the Dead Sea bitumen, as well as the Fayum mummy resin based on this bitumen. The advantages of using the method of identifying bitumen in mummy resins based on relative content of vanadium, nickel, and molybdenum were revealed.

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