Search results

1

NEW AFFINITY SORBENTS FOR PURIFICATION OF RECOMBINANT PROTEINS WITH THE USE OF CHITIN-BINDING DOMAIN AS AN AFFINITY TAG

100%

Kurek D. V., Lopatin S. A., Tikhonov, V. E., Varlamov V. P.

Progress on Chemistry and Application of Chitin and its Derivatives

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2010

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vol. 15

41 - 46

EN

With the increasing amounts of recombinant proteins production the problem of effective purification of produced proteins became one of major topics for research nowadays. Affinity chromatography proved to be the most dominant method for this aim and application of chitin based affinity sorbents in combination with use of chitin-binding domain as an affinity tag for purification of recombinant proteins showed its efficiency even in comparison with commercially available systems.

2

BIODISTRIBUTION OF DOXORUBICIN-LOADED SUCCINOYL CHITOSAN NANOPARTICLES IN MICE INJECTED VIA INTRAVENOUS OR INTRANASAL ROUTES

100%

Zubareva A., Shcherbinina T., Varlamov V. P., Svirshchevskaya E.

Progress on Chemistry and Application of Chitin and its Derivatives

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2014

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vol. 19

145-154

EN

Chitosan (Chi) is an extremely promising natural biopolymer with remarkable potency for the development of drug and vaccine delivery nanosystems. Various Chi derivatives are used to form nanoparticles (NPs) with unique properties. However, the efficacy of the therapy delivered by Chi NPs depends significantly on NP biodistribution in the body. The aim of this study was the analysis of biodistribution of NPs formed by succinoyl Chi and loaded with doxorubicin (SCNPDOX). We compared the distribution of free DOX and SCNP-DOX after intravenous (i.v.) and intranasal (i.n.) delivery into tumour-bearing mice. Distribution of DOX and SCNP-DOX was comparable after i.v. injection while they differed significantly after i.n. instillation.

3

THE FORMATION OF HYDROGELS BASED ON CHITOSAN AND ITS WATER-SOLUBLE DERIVATIVES

100%

Il’ina A. V., Shagdarova B. T., Lunkov A. P., Varlamov V. P.

Progress on Chemistry and Application of Chitin and its Derivatives

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2020

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vol. 25

5 - 15

EN

This review considers articles on the formation of hydrogels based on chitosan as well as succinylated and quaternized chitosan derivatives. They are synthesized using low toxicity reagents, under ordinary conditions (low production costs). Chitosan derivatives are soluble in an extended range of pH values and characterized by mucoadhesiveness, bioavailability and biodegradability, which extends the potential of their medical applications. One of the most important properties of chitosan and its derivatives is the ability to form hydrogels. Depending on the nature of the bonds that occur during formation, hydrogels are divided into chemically or physically crosslinked, or a mixture of the two. Chemically crosslinked gels have covalent bonds, while physically crosslinked gels are formed by noncovalent interactions, for example, ionic. Mixed hydrogels have both types of crosslinking.

4

CELL BINDING AND PENETRATION OF QUATERNIZED CHITOSAN DERIVATIVES

100%

Zubareva A. A., Shagdarova B. T., Varlamov V. P., Svirshchevskaya E. V.

Progress on Chemistry and Application of Chitin and its Derivatives

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2016

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vol. 21

217-223

EN

Chitosan (Ch) is an attractive biopolymer with multiple reactive groups. However it is poorly soluble at neutral pH. Quaternization improves its solubility and permits the development of various positively charged drug delivery systems. The aim of this work was to study the solubility, toxicity, cell binding, and penetration of 20 kDa chitosan with 9, 40, 58 and 98% of quaternary ammonium group substitution (ChQ1 to ChQ4 accordingly). We showed that ChQ with substitution degree >40% was soluble in a wide pH range. Unexpectedly ChQ2 and ChQ3 were more toxic to cells than Ch, ChQ1 and ChQ4. Higher toxicity of ChQ was found against macrophage like cell line RAW264.7 than against epithelial cells MiaPaCa-2. All ChQ, in contrast to unmodified Ch, easily bound and penetrated the cells with the highest uptake by ChQ4. Thus, quaternized chitosan derivatives can be used for biomedical applications.

5

MOLECULAR STRUCTURE AND FORMATION OF CHITOSAN AND PECTIN BASED THIN FILMS

100%

Chudinova Y. V., Kurek D. V., Varlamov V. P.

Progress on Chemistry and Application of Chitin and its Derivatives

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2016

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vol. 21

18-26

EN

In this study using methods of Atomic force microscopy (AFM) and Quartz crystal microbalance with dissipation monitoring (QCM-D) the special characteristics of formation and architecture of thin films coatings based on natural polysaccharides chitosan and pectin were investigated. A layer-by-layer (LbL) deposition technique for assembling of oppositely charged layers was used. The main factors, which have an influence on the process of thin film formation and molecular structure of these coatings, were investigated.

6

THE EFFECT OF CHITOSAN HYDROLYSATE ON THE FUNGI ALTERNARIA SOLANI, FUSARIUM SOLANI AND RHIZOCTONIA SOLANI IN VITRO

100%

Shagdarova B. T., Karpova N. V., Il’ina A. V., Varlamov V. P.

Progress on Chemistry and Application of Chitin and its Derivatives

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2021

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vol. 26

200-209

EN

Chitosan hydrolysate was obtained using nitric acid; the prevailing fraction had a molecular weight of 30 kDa and a deacetylation degree of 95%. The effect of chitosan hydrolysate when added to potato dextrose agar (PDA) in different concentrations (0.5, 1, 1.5, 2, 4, 6 and 8 mg/mL) was studied on the growth of the fungi Alternaria solani Sorauer, Fusarium solani (Mart.) Sacc. and Rhizoctonia solani J.G. Kühn. A. solani was the most sensitive to the addition of chitosan hydrolysate to PDA in radial growth experiments. On days 3 and 7 of incubation, the antifungal activity of the phytopathogen growth was 69%-92% and 69%-88%, respectively, in the concentration range of 0.5-2 mg/ml.

7

THE INHIBITION OF HUMAN PLATELET AGGREGATION BY A LOW-MOLECULAR WEIGHT CHITOSAN

88%

Drozd N. N., Logvinova Y. S., Shagdarova B. T., Il’ina A. V., Varlamov V. P.

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vol. 23

55 - 65

EN

Chitosan derivatives were obtained by chemical (MW of 6 kDa, DD 99% - Ch6/99; MW13 kDa, DD 98% - Ch13/98) and enzymatic (MW of 5 kDa, DD 85% - Ch5/85; MW of 10 kDa, DD 85% - Ch10/85) depolymeri-sation of chitosan with a MW of 334 and 1000 kDa. Chitosan derivatives (almost identical MW pairs and different DD) possessed insignificant an-ticoagulant activity, did not promote human platelet aggregation and re-duced ADP or collagen-induced platelet aggregation. The studied sam-ples at a concentration of 2 mg/ml reduced the aggregation of platelets more than twice induced in 2x10-6M and 1x10-5M concentrations; at weak activation in 2x10-6M, the Ch10/85 sample was the most effective. The Ch6/99 and Ch13/98 samples were 20 times more effective at the inhibi-tion of collagen-induced platelet aggregation than the Ch10/85 sample. The latter can be explained by the greater value of positive charge (DD) and polydispersity (Mw/Mn) of chitosan samples obtained by chemical de-polymerisation

8

FORMATION AND CHARACTERIZATION OF SUCCINOYL CHITOSAN PARTICLES LOADED WITH WARNERIN

76%

Shagdarova B. T., Ilyina A. V., Lopatin S. A., Korobov V. P., Lemkina L. M., Varlamov V. P.

Progress on Chemistry and Application of Chitin and its Derivatives

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2015

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vol. 20

246-253

EN

This study aims to obtain nanoparticles based on succinoyl chitosan loaded with Warnerin (War-SCNPs), low molecular weight cationic peptide. The nanoparticles of succinoyl chitosan (SCNPs) were prepared by salt coacervation method, and Warnerin loading efficiency on SCNPs was reached 75% in the optimum conditions, particularly, ration (SCNPs : peptide) was equal to (1.75 : 1, μg / ml ). Formed War-SCNPs were stable, had a weak electric charge from (-4.4) to (-14,6) mV. Determining of SCNPs size showed that a main fraction of SCNPs had the size of 160 nm, and after the peptide sorption War-SCNPs size increased up to 330 nm. The experimental data of this study will likely impact War-SCNPs use as therapeutic delivery systems of the peptide to be administered parenteral.

9

PROTEIN DELIVERY BY NANOPARTICLES FORMED BY CHITOSAN-N-ACYL DERIVATIVES

76%

Zubareva A. А., Ilyina A. V., Levov А. N., Zueva V. S., Svirshchevskaya Е. V., Varlamov V. P.

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EN

Biodegradable nanoparticulated carriers have important potential applications for administration of therapeutic proteins and peptides. Chitosan based nanoparticles have attracted attention due to their biological properties such as biodegrability and biocompatibility. However, chitosan nanoparticles are not stable in colloid form. Therefore, to increase the stability of these particles is an important problem. The aim of this work was to obtain stable nanoparticles formed by N-acyl derivatives of chitosan by ionic gelation and to investigate their ability to interact with acidic, neutral and basic proteins.

10

THROMBORESISTANT SILICON PLATES MODIFIED WITH CHITOSAN AND HEPARIN BY THE LAYER-BY-LAYER ASSEMBLY METHOD

64%

Drozd N. N., Shagdarova B. T., Zhuikova Y. V., Il’ina A. V., Vasiliev M. N., Vasilieva T. M., Hein A. M., Varlamov V. P.

Progress on Chemistry and Application of Chitin and its Derivatives

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2019

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vol. 24

5 - 22

EN

Fifteen samples of silicone plates (PlateSi, area=12 cm2), with surfaces modified layer-by-layer with chitosan and unfractionated heparin, were obtained. The sample surfaces were pre-treated by cold oxygen plasma in a planar-type plasma chemical reactor with 50 W power before coating with layered polysaccharides. Pre-treatment was carried out in two alternative operation modes of the reactor, namely in the plasma etching mode and in the reactive-ion etching mode. Thromboresistance was assessed in vitro in contact with human blood. The thromboresistant silicon plates, modified layer-by-layer (3, 5, 7, and 9 bilayers) with chitosan, with molecular weights of 65 kDa, increased with the increase in the number of layers, up to 5. An increase in the duration of thromboresistance was observed in layer-by-layer modification of the surface of the plates with chitosan with a molecular weight of 200 kDa or with quaternized chitosan with a molecular weight of 200 kDa. Some samples of highly thromboresistant, modified PlateSi contributed to the adhesion of platelets and the haemolysis of red blood cells to a lesser extent than untreated silicon plates. The three most promising samples of modified PlateSi were selected.

Refine search results

NEW AFFINITY SORBENTS FOR PURIFICATION OF RECOMBINANT PROTEINS WITH THE USE OF CHITIN-BINDING DOMAIN AS AN AFFINITY TAG

BIODISTRIBUTION OF DOXORUBICIN-LOADED SUCCINOYL CHITOSAN NANOPARTICLES IN MICE INJECTED VIA INTRAVENOUS OR INTRANASAL ROUTES

THE FORMATION OF HYDROGELS BASED ON CHITOSAN AND ITS WATER-SOLUBLE DERIVATIVES

CELL BINDING AND PENETRATION OF QUATERNIZED CHITOSAN DERIVATIVES

MOLECULAR STRUCTURE AND FORMATION OF CHITOSAN AND PECTIN BASED THIN FILMS

THE EFFECT OF CHITOSAN HYDROLYSATE ON THE FUNGI ALTERNARIA SOLANI, FUSARIUM SOLANI AND RHIZOCTONIA SOLANI IN VITRO

THE INHIBITION OF HUMAN PLATELET AGGREGATION BY A LOW-MOLECULAR WEIGHT CHITOSAN

FORMATION AND CHARACTERIZATION OF SUCCINOYL CHITOSAN PARTICLES LOADED WITH WARNERIN

PROTEIN DELIVERY BY NANOPARTICLES FORMED BY CHITOSAN-N-ACYL DERIVATIVES

THROMBORESISTANT SILICON PLATES MODIFIED WITH CHITOSAN AND HEPARIN BY THE LAYER-BY-LAYER ASSEMBLY METHOD