Tuning chitosan properties to enhance blood coagulation.

The search for new hemostatic materials remains a priority for researchers, as the problem of uncontrolled hemorrhage during surgical interventions or traumatic injuries represents a significant challenge. The objective of the study was to identify novel polysaccharide structures with enhanced hemostatic properties based on chitosan. The number of chitosan derivatives with two substituents was synthesized and characterized by H NMR, FTIR.

Effects of Chitosan and -Succinyl Chitosan on Metabolic Disorders Caused by Oral Administration of Olanzapine in Mice.

Background: The issue of human mental health is gaining more and more attention nowadays. However, most mental disorders are treated with antipsychotic drugs that cause weight gain and metabolic disorders, which include olanzapine (OLZ). The search for and development of natural compounds for the prevention of obesity when taking antipsychotic drugs is an urgent task.

Three-Dimensional Planimetry Assessment of Dental Plaque-Covered Area Reduction after Rinsing with 0.2% Sodium Hypochlorite Solution as Part of a Guided Biofilm Therapy Protocol-Pilot Longitudinal Study.

: Less often employed as a rinsing solution for controlling oral biofilms, NaOCL was used in oral rinses at various concentrations in steps 1 and 4 of periodontal therapy. The aim of this study was to quantitatively evaluate the biofilm-disruptive properties of a 0.2% NaOCl solution in standardized oral rinses using dedicated plaque-disclosing agents and 3D scanning methods in patients undergoing the regular Guided Biofilm Therapy protocol.

Evaluation of Chemical and Biological Properties of Biodegradable Composites Based on Poly(3-hydroxybutyrate) and Chitosan.

In this study, composite films and scaffolds of polyester poly(3-hydroxybutyrate) and polysaccharide chitosan obtained via a simple and reproducible blending method using acetic acid as a solvent were considered. The degradation process of the films was studied gravimetrically in a model biological medium in the presence of enzymes in vitro for 180 days. The kinetics of weight reduction depended on the amount of chitosan in the composition.

Chemical modification of chitosan for developing of new hemostatic materials: A review.

Uncontrolled bleeding that occurs during surgery, trauma, and in combat conditions is critical and require immediate action. Chitosan is a polysaccharide, obtained from natural sources with unique biological properties. It is often used as basis for local hemostatic agents (LHA).

Anti-Obesity Effects of Chitosan and Its Derivatives.

The number of obese people in the world is rising, leading to an increase in the prevalence of type 2 diabetes and other metabolic disorders. The search for medications including natural compounds for the prevention of obesity is an urgent task. Chitosan polysaccharide obtained through the deacetylation of chitin, and its derivatives, including short-chain oligosaccharides (COS), have hypolipidemic, anti-inflammatory, anti-diabetic, and antioxidant properties.

New N-Methylimidazole-Functionalized Chitosan Derivatives: Hemocompatibility and Antibacterial Properties.

Novel imidazole derivatives of the low molecular weight chitosan N-(2-hydroxypropyl)-1H-1,2,3-triazol-4-yl)methyl)-1-methyl-1H-imidazol-3-ium chitosan chloride (NMIC) were synthesized using copper-catalyzed azide-alkyne cycloaddition (CuAAC). The degrees of substitution (DSs) for the new derivatives were 18-76%. All chitosan derivatives (2000 µg/mL) were completely soluble in water.

Preparation and characterization of poly(3-hydroxybutyrate)/chitosan composite films using acetic acid as a solvent.

Poly(3-hydroxybutyrate) and chitosan are among the most widely used polymers for biomedical applications due to their biocompatibility, renewability and low toxicity. The creation of composite materials based on biopolymers belonging to different classes makes it possible to overcome the disadvantages of each of the components and to obtain a material with specific properties. Solving this problem is associated with difficulties in the selection of conditions and solvents for obtaining the composite material.

Synthesis of Selenium Nanoparticles Modified by Quaternary Chitosan Covalently Bonded with Gallic Acid.

Quaternary chitosan derivative with covalently bonded antioxidant (QCG) was used as media for synthesis of selenium nanoparticles (SeNPs). SeNPs were characterized using AFM, TEM, and DLS methods. The data confirmed the formation of stable nanoparticles with a positive charge (34.

Protective Properties of Copper-Loaded Chitosan Nanoparticles against Soybean Pathogens pv. and pv. .

Soybeans are a valuable food product, containing 40% protein and a large percentage of unsaturated fatty acids ranging from 17 to 23%. pv. (Psg) and pv.

Investigation of FBMC-OQAM Equalization with Real Interference Prediction Algorithm Properties for MIMO Transmission Scheme.

Increasing the data transfer rate is an urgent task in cellular, high-frequency (HF) and special communication systems. The most common way to increase the data rate is to expand the bandwidth of the transmitted signal, which is often achieved through the use of multitone systems. One such system is the filter bank multicarrier (FBMC).

Effect of Seed Priming with Chitosan Hydrolysate on Lettuce () Growth Parameters.

Seed priming increases germination, yield, and resistance to abiotic factors and phytopathogens. Chitosan is considered an ecofriendly growth stimulant and crop protection agent. Chitosan hydrolysate (CH) is an unfractionated product of hydrolysis of high-molecular-weight crab shell chitosan with a molecular weight of 1040 kDa and a degree of deacetylation of 85% with nitric acid.

Biocomposite Materials Based on Poly(3-hydroxybutyrate) and Chitosan: A Review.

One of the important directions in the development of modern medical devices is the search and creation of new materials, both synthetic and natural, which can be more effective in their properties than previously used materials. Traditional materials such as metals, ceramics, and synthetic polymers used in medicine have certain drawbacks, such as insufficient biocompatibility and the emergence of an immune response from the body. Natural biopolymers have found applications in various fields of biology and medicine because they demonstrate a wide range of biological activity, biodegradability, and accessibility.

The Application of Chitosan for Protection of Cultural Heritage Objects of the 15-16th Centuries in the State Tretyakov Gallery.

Microorganisms are one of the main factors in the deterioration of cultural heritage, in particular art paintings. The antiseptics currently used in painting have significant limitations due to insufficient effectiveness or increased toxicity and interaction with art materials. In this regard, the actual challenge is the search for novel materials that effectively work against microorganisms in the composition with painting materials and do not change their properties.

Investigation of the Antioxidant Properties of the Quaternized Chitosan Modified with a Gallic Acid Residue Using Peroxidase that Produces Reactive Oxygen Species.

Chitosan modified with a (2-hydroxy-3-trimethylammonium) propyl group and gallic acid residue, or quaternized chitosan with gallic acid (QCG), was synthesized. Antioxidant properties of the produced QCG have been investigated. Peroxidase in combination with NADH and salicyl hydroxamate (SHAM) caused consumption of oxygen and production of H2O2 in aqueous solution as a result of O2 reduction in the peroxidase-oxidase reactions.

Simple method for ultrasound assisted «click» modification of azido-chitosan derivatives by CuAAC.

New quaternized chitosan derivatives HT-TMC were synthesized as a result of copper catalyzed azide-alkyne [3 + 2] cycloaddition (CuAAC). The structure of the HT-TMC was verified by 2D NMR. The synthesis was carried out as a result of the formation of Cu(I) in situ, under the action of ultrasound in aerobic conditions in the presence of acetic acid and metallic copper (copper turnings).

Evaluation of Antibacterial and Antifungal Properties of Low Molecular Weight Chitosan Extracted from Relative to Crab Chitosan.

This study shows the research on the depolymerisation of insect and crab chitosans using novel enzymes. Enzyme preparations containing recombinant chitinase Chi 418 from , chitinase Chi 403, and chitosanase Chi 402 from , all belonging to the family GH18 of glycosyl hydrolases, were used to depolymerise a biopolymer, resulting in a range of chitosans with average molecular weights (M) of 6-21 kDa. The depolymerised chitosans obtained from crustaceans and insects were studied, and their antibacterial and antifungal properties were evaluated.

Collagen/Chitosan Gels Cross-Linked with Genipin for Wound Healing in Mice with Induced Diabetes.

Diabetes mellitus continues to be one of the most common diseases often associated with diabetic ulcers. Chitosan is an attractive biopolymer for wound healing due to its biodegradability, biocompatibility, mucoadhesiveness, low toxicity, and hemostatic effect. A panel of hydrogels based on chitosan, collagen, and silver nanoparticels were produced to treat diabetic wounds.

Effect of Oligochitosan on Experimental Venous Thrombosis in Guinea Pigs.

Oligochitosan Сh10/85 with a molecular weight of 10 kDa and a deacetylation degree of 85% prevented the development of experimental venous thrombosis in guinea pigs after intravenous administration in a dose of 30 mg/kg. In a concentration of 0.005-0.

Antifungal action of chitosan in combination with fungicides in vitro and chitosan conjugate with gallic acid on tomatoes against Botrytis cinerea.

In the present work, a positive effect was obtained by using low molecular weight chitosan compounds in combination with synthetic fungicides. Antifungal activity against Botrytis cinerea, determined by the radial growth method, was more than 75%, with a 25 × 10 g/L concentration of fludioxonil or difenoconazole in compounds. Metabolic activity of B.

Obtaining chitin, chitosan and their melanin complexes from insects.

Interest in insects as a source of valuable biologically active substances has significantly increased over the past few years. Insects serve as an alternative source of chitin, which forms up to 40% of their exoskeleton. Chitosan, a deacetylated derivative of chitin, attracts the attention of scientists due to its unique properties (sorption, antimicrobial, film-forming, wound healing).

Physicochemical and biological characteristics of chitosan/κ-carrageenan thin layer-by-layer films for surface modification of nitinol.

Thin films based on the natural polysaccharides κ-carrageenan (Carr) and chitosan (Chit) were formed by layer-by-layer deposition technique. Surface topography and mechanical characteristics (Young's modulus, adhesion strength) of the polymer films with different number of layers were determined using various modes of atomic force microscopy (AFM). Polymer films were used to deposit on the surface of nitinol (NiTi) plates.

Hemocompatibility of Silver Nanoparticles Based on Conjugate of Quaternized Chitosan with Gallic Acid in In Vitro Experiments.

We studied hemocompatibility of silver nanoparticles synthesized on the basis of a conjugate of quaternized chitosan with gallic acid (QChit-Gal). For the three variants of silver particles (Nos. 1, 2, and 3), the QChit-Gal:AgNO ratio was 5:1, 5:3, and 1:1, respectively.

Chitin/Chitosan and Its Derivatives: Fundamental Problems and Practical Approaches.

In this review, we present the data on the natural occurrence of chitin and its partially or fully deacetylated derivative chitosan, as well as their properties, methods of modification, and potential applications of derivatives with bactericidal, fungicidal, and antioxidant activities. The structure and physicochemical characteristics of the polymers, their functions, and features of chitin microbial synthesis and degradation, including the processes occurring in nature, are described. New data on the hydrolytic microorganisms capable of chitin degradation under extreme conditions are presented.

Synthesis of silver nanoparticles using gallic acid-conjugated chitosan derivatives.

In presented study, various chitosan derivatives containing covalently bounded gallic acid were obtained: chitosan with gallic acid (CG), quaternized chitosan with gallic acid (QCG), and succinylated chitosan with gallic acid (SCG). Chitosan derivatives were used as stabilizing and reducing agents in the synthesis of silver nanoparticles (AgNPs). The dimensional characteristics of nanomaterials were determined by transmission electron (TEM), dynamic light scattering (DLS) and atomic force (AFM) microscopy, antibacterial activity (against E.