The interactions of one of the most famous enzymes, lysozyme, with carboxylated nanodiamonds in water were studied. It was found that stable complexes are formed as a result of lysozyme adsorption on the surface of nanodiamonds. Based on the obtained adsorption isotherms and change in the fluorescence of nanodiamonds during the adsorption of lysozyme on them, it is concluded that lysozyme is adsorbed on carboxylated nanodiamonds in two layers. Numerical estimates and IR absorption spectroscopy data showed that the lysozyme has different adsorption orientations in the first and second layers, with preferential side-on and end-on orientations, correspondingly. Moreover, in the first layer, lysozyme undergoes significant conformational changes. The enzymatic activity of adsorbed lysozyme in both layers is discussed.

Efficiency of adsorption of nucleic acid nitrogenous bases (NBs) on carboxylated detonation nanodiamond (DND−COOH) particles in aqueous media at pH = 7.4−7.6 and pH = 13.4 was investigated using Raman spectroscopy and infrared (IR) absorption spectroscopy. A significant difference in the adsorption activity of NDs toward four different individual NBs, guanine, adenine, cytosine, and thymine, had been observed. The highest adsorption activity on DND−COOH was observed for cytosine and, in descending order, for adenine and thymine. At the same time, adsorption activities of the adenine−thymine and guanine−cytosine complementary pairs on nanodiamonds (NDs) were similar. Analysis of the hydrogen bond parameters in the adsorption of complementary pair adenine−thymine on the ND surface had been done using the density functional theory-based molecular modeling. The theoretical calculations are consistent with the experimental results.

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Elaboration of methods for the control of biochemical reactions with deoxyribonucleic acid (DNA) strands is necessary for the solution of one of the basic problems in the creation of biocomputers-improvement in the reliability of molecular DNA computing. In this paper, the results of the solution of the four-parameter inverse problem of laser Raman spectroscopythe determination of the type and concentration of each of the DNA nitrogenous bases in multi-component solutions-are presented.

In this study, the interaction between DNA and the surface of detonation nanodiamonds and nanodiamonds with NV centers is investigated, and the quantitative parameters of this interaction are calculated. The influence of interaction of DNA with nanodiamonds on the fluorescent properties of nanodiamonds is established. A correlation was found between the efficiency of DNA interaction with the surface of the detonation nanodiamonds and the changes of their fluorescence: the more DNA bonds with the nanodiamond surface groups -the stronger the fluorescence of detonation nanodiamonds increases in water.

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