Nanotechnologies involving physical methods of tumor destruction using functional oligonucleotides are promising for targeted cancer therapy. Our study presents magnetodynamic therapy for selective elimination of tumor cells in vivo using DNA aptamer-functionalized magnetic nanoparticles exposed to a low frequency alternating magnetic field. We developed an enhanced targeting approach of cancer cells with aptamers and arabinogalactan. Aptamers to fibronectin (AS-14) and heat shock cognate 71 kDa protein (AS-42) facilitated the delivery of the nanoparticles to Ehrlich carcinoma cells, and arabinogalactan (AG) promoted internalization through asialoglycoprotein receptors. Specific delivery of the aptamer-modified FeAG nanoparticles to the tumor site was confirmed by magnetic resonance imaging (MRI). After the following treatment with a low frequency alternating magnetic field, AS-FeAG caused cancer cell death in vitro and tumor reduction in vivo. Histological analyses showed mechanical disruption of tumor tissues, total necrosis, cell lysis, and disruption of the extracellular matrix. The enhanced targeted magnetic theranostics with the aptamer conjugated superparamagnetic ferroarabinogalactans opens up a new venue for making biocompatible contrasting agents for MRI imaging and performing non-invasive anti-cancer therapies with a deep penetrated magnetic field.

Samples of arabinogalactan (AG) were isolated by aqueous extraction from wood of different larch species (Larix sibirica Ledeb., Larix gmelinii (Rupr.) Rupr., Larix cajanderi Mayr., and Larix olgensis var. Koreana) and studied by HPLC, IR spectroscopy, and quantitative ¹³C NMR spectroscopy. The wood of the studied larch species was shown to contain significant amount of arabinogalactan (10–17% of the a.d.w. mass) and could be a source of its industrial production. The studied AG samples had similar structural and molecular-mass characteristics. This fact could facilitate the product standardization during its industrial production both from the wood of a single larch species and from mixed raw materials.

A distribution of extractive substances by height on the trunk and radius of the wood of the Siberian larch (Larix sibirica Ledeb.) was investigated. The maximum flavonoid content in terms of dihydroquercetin (the main flavonoid of the larch wood) was shown to be in the butt part of the tree. In the radial direction, this parameter increased from the center to periphery of the heartwood and reached the maximum value at the sapwood boundary. The maximum content of arabinogalactan (AG) was observed in the bottom and in the top of the trunk. The distribution of the extractive substances was studied in roots of the Siberian larch for the first time.

To raise the efficacy and the selectivity of known medicinal substances (MS), methods have recently been developed to create systems for their directed transport in the body using various carriers. The problem of decreasing the toxicity and increasing the selectivity of antitumor MSs is particularly relevant. In recent years, studies are underway for the development of conjugates of MSs and the natural polymers, in particular, the non-starch polysaccharides, many of which manifest antitumor and immunomodulatory properties. Owing to the unique combination of physicochemical and biological properties, arabinogalactan from larch wood (AG) is one of the most promising tools for the development of complex preparations with elevated bioavailability and reduced toxicity. The aim of the present work is to obtain mechanocomposites of cyclophosphamide (CPA) with the initial arabinogalactan (molecular mass 16 645 Da) and its fragments (molecular mass 8380 Da) and to study their physicochemical properties. According to IR and ¹³С, ¹⁵N and ³¹Р NMR spectroscopy, long-term mechanochemical treatment does not lead to a change in chemical composition of CPA molecules, only the formation of hydrogen bonds NH···OH is observed. The data on X-ray analysis, IR and multinuclear NMR spectroscopy show that, with a weight ratio of 1 : 5 and 1 : 10, disordering of CPA crystallographic structure and its molecular dispersion without chemical interaction of the components occur in the matrix of the polysaccharide with mechanical treatment of mixtures of CPA–AG over 4–12 hours.

Over the past decades, researchers have increasingly turned to natural compounds and preparations created on their basis. Biologically active terpenoids, in particular, natural sesquiterpene lactones, are of great interest. One of the rich sources of these compounds is a plant of the genus Artemisia, whose representative is wormwood Artemisia glabella Kar et Kir., Growing on the territory of Central Kazakhstan. In the study of the chemical composition of wormwood, a new biologically active compound, sesquiterpenic lactone arglabin, with antitumor and radiosensitizing properties has been isolated. The antitumor drug "Arglabin" is used in oncological clinics of the Republic of Kazakhstan, the Russian Federation, Uzbekistan, the Republic of Georgia, Belarus, Kyrgyzstan and Tajikistan in the complex therapy of tumors of the breast, lung, liver, etc. The purpose of this work is to study the physicochemical properties of mechanically treated arglabin and its mixture with a larch water–soluble polysaccharide arabinogalactan, obtained by mechanochemical means. According to IR, UV and NMR 13С spectroscopy, long–term mechanochemical treatment does not lead to a change in the chemical composition of arglabin molecules. All the spectra obtained are identical to the spectra of the initial (not mechanically treated) arglabin. Using X–ray analysis, it was shown that in the mechanocomposites of arglabin with arabinogalactan there is no disordering of the crystal structure of arglabin and its molecular dispersion in the polysaccharide matrix does not occur.

The extractive substances of the wood of Cajander larch (Larix cajanderi Mayr.) growing in the areas of Magadan oblast under various climatic conditions have been investigated. It has been found that the investigated wood contains up to 4.5% of flavonoids and up to 15.5% of water-soluble polysaccharide arabinogalactan that defines the perspective of its application for the industrial production of these valuable biologically active substances.