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The catalytic performance of multi-walled carbon nanotubes (MWCNTs) with different surface chemistry was studied in the decomposition reaction of H 2 O 2 at various values of pH and temperature. A comparative analysis of experimental and quantum chemical calculation results is given. It has been shown that both the lowest calculated activation energy (~18.9 kJ/mol) and the highest rate cons tant correspond to the N-containing CNT. The calculated chemisorption energy values correlate with the operation stability of MWCNTs. Based on the proposed quantum chemical model it was found that the catalytic activity of carbon materials in electron tran sfer reactions is controlled by their electron donor capability.

The aim of the proposed work was to analyze the toxicity of oxidized carbon nanotubes (CNTox), functionalized by doxorubicin (CNT-Dox) and fluorescein (CNT-FITC) on cell and organism level. The cytotoxic effect of CNTox, CNT-Dox, and CNT-FITC was analyzed on tumor cells in vitro (2-D, 3-D cultures) and on Balb2/c mice model in vivo. As a result, it was demonstrated the possibility of doxorubicin immobilization on the surface of CNT and controlled release of doxorubicin (Dox) from the surface of CNT. Dox immobilization coincident with decreasing cytotoxic effect CNT-Dox compared with free Dox. Breakdown of peptide bonds with CNT surface led to the release of doxorubicin and dose-dependent enhancement of the cytotoxic effect of CNTs and Dox. The combined cytotoxic effect from CNTs, Dox, and trypsin on the survival of tumor cells was shown. At the organism level, it was investigated the effect of the obtained nanostructures on the state of hepatic enzymatic system, the protein metabolism, and cell blood composition of the experimental animals. CNTox influence in vivo model was statistically the same as control. CNT-Dox demonstrated lower total organism toxic effect compared to the pure doxorubicin. Deviations in the cell blood composition indicated a general toxic effect of CNT-Dox, but it was more moderate compared with of pure doxorubicin. From the data obtained, we concluded that binding CNTs with doxorubicin allows reducing toxicity of the doxorubicin on the general biochemical indicators of blood and violations in the blood cells composition in vivo. At the same time, the combined effect of CNTs and doxorubicin after drug release allowed us to achieve greater efficacy in suppressing tumor growth in vitro.

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The actual task of oncology is effective treatment of cancer while causing a minimum harm to the patient. The appearance of polymer nanomaterials and technologies launched new applications and approaches of delivery and release of anticancer drugs. The goal of work was to test ultra dispersed diamonds (UDDs) and onion-like carbon (OLCs) as new vehicles for delivery of antitumor drug (doxorubicin (DOX)) and specific antibodies to tumor receptors. Stable compounds of UDDs and OLCs with DOX were obtained. As results of work, an effectiveness of functionalization was 2.94 % w/w for OLC-DOX and 2.98 % w/w for UDD-DOX. Also, there was demonstrated that UDD-DOX and OLC-DOX constructs had dose-dependent cytotoxic effect on tumor cells in the presence of trypsin. The survival of adenocarcinoma cells reduced from 52 to 28 % in case of incubation with the UDD-DOX in concentrations from 8.4–2.5 to 670–20 μg/ml and from 72 to 30 % after incubation with OLC-DOX. Simultaneously, antibodies to epidermal growth factor maintained 75 % of the functional activity and specificity after matrix-assisted pulsed laser evaporation deposition. Thus, the conclusion has been made about the prospects of selected new methods and approaches for creating an antitumor agent with capabilities targeted delivery of drugs.

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