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The development of an aptamer-based electrochemical sensor for lung cancer detection is presented in this work. A highly specific DNA-aptamer, LC-18, selected to postoperative lung cancer tissues was immobilized onto a gold microelectrode and electrochemical measurements were performed in a solution containing the redox marker ferrocyanide/ferricyanide. The aptamer protein targets were harvested from blood plasma of lung cancer patients by using streptavidin paramagnetic beads and square wave voltammetry of the samples was performed at various concentrations. In order to enhance the sensitivity of the aptasensor, silica-coated iron oxide magnetic beads grafted with hydrophobic C8 and C4 alkyl groups were used in a sandwich detection approach. Addition of hydrophobic beads increased the detection limit by 100 times. The detection limit of the LC-18 aptasensor was enhanced by the beads to 0.023 ng/mL. The formation of the aptamer – protein – bead sandwich on the electrode surface was visualized by electron microcopy. As a result, the electrochemical aptasensor was able to detect cancer-related targets in crude blood plasma of lung cancer patients.

Two ways of catalytic depolymerization of native and isolated wood lignins are described: the peroxide delignification of hardwood (aspen, birch) and softwood (abies) in the medium of acetic acidwater over TiO 2 catalyst and the thermal dissolution of organosolv lignins (ethanol-lignin and acetone-lignin) in supercritical alcohols (ethanol and butanol) over solid Ni-containing catalysts. The catalyst TiO 2 in rutile modification has the higher activity in wood peroxide delignification at 100°C as compared to TiO 2 in anatase modification. The results of kinetic studies and optimization of the processes of peroxide depolymerization of hardwood (aspen, birch) and softwood (abies) lignins in the medium of acetic acidwater over catalyst TiO 2 (rutile) at mild conditions (≤ 100°C, atmospheric pressure) are compared. The catalyst TiO 2 initiates the formation of OH • and OOH • radicals from H 2 O 2 which promote the oxidative fragmentation of wood lignin. In this case, the peroxide depolymerization of softwood lignin, constructed from phenylpropane units of guaiacyl-type proceeds more difficult than the hardwood lignins, mainly containing syringyl-type units. The solid and soluble products of peroxide catalytic delignification of wood under the optimized conditions were studied by FTIR, XRD, GC-MS and chemical methods. Regardless of the nature of wood the cellulosic products have a structure similar to microcrystalline cellulose. The soluble products mainly consist of monosaccharides and organic acids. Aromatic compounds are present only in a low amount which indicates the oxidative degradation of aromatic rings of lignin phenylpropane units under the used conditions of wood catalytic delignification. The processes of thermal dissolution of acetone-lignin and ethanol-lignin from aspenwood in supercritical ethanol and butanol over Ni-containing catalyst (NiCu/SiO 2 , NiCuMo/SiO 2) are compared. The composition, structure and thermal properties of organosolv lignins were studied with the use of FTIR, GPC, 1 H-13 C HSQC NMR, DTA and elemental analysis. The influence of a composition of Ni-containing catalyst on the thermal conversion in supercritical butanol and ethanol of ethanol-lignin and acetone-lignin was established. The highest conversion of lignins (to 93% wt.) in supercritical alcohols and the highest yield of liquid products (to 90 % wt.) were achieved at 300 °C in the presence of catalyst NiCuMo/SiO 2. Scheme of green biorefinery of wood based on the use of non-toxic and low-toxic reagents (H 2 O 2 , H 2 O, acetic acid, ethanol, butanol) and solid catalysts (TiO 2 , NiCuMo/SiO 2) is suggested.

The effects of sulfated ZrO 2 and ZrO 2 -Al 2 O 3 catalysts and acidic zeolite catalysts with various Si/Al ratios on the thermal conversion of alkali lignin in supercritical ethanol at 300-400°C and on the com position of the resulting products have been investigated. All of the catalysts enhance lignin conversion into liquid products. The strongest effect with the catalysts based on sulfated ZrO 2 is attained at 400°C; with the zeolites, at 350°C. The catalysts diminish the concentration of phenol and its derivatives and increase the concentration of ethers (mainly the 1,1 diethoxyethane concentration) in the liquid products. The zeolite catalysts are preferable, since the reaction over the ZrO 2 containing catalysts produces gaseous compounds in higher yields. The maximum lignin conversion and a high yield of low boiling liquid products are achieved at 350°C with the zeolite catalyst with Si/Al = 30, which contains a high concentration of acid sites that are stable at elevated temperatures. The most abundant phenolic liquid products of lignin conversion over the zeolite catalysts at 350°C are methoxyphenols and their methylated and ethylated derivatives.