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1

Chitosan dichloro acetic acid salts

100%

Wojtasz-Pająk A.

|

vol. 15

55 - 62

EN

The salts of dichloroacetic acid were obtained from chitosans of different deacetylation degrees (69÷97%) and viscosity-average molecular weights (61÷327 kDa). The mole ratio of dichloroacetic acid to amine groups was 1. The chemical and physical properties of the salts were evaluated by determining the dry weight, the content of ash, acid, insoluble substances, kinematic viscosity, and pH. The studied salts had a low contents of water (<10%), inorganic pollutants (<0.2%), and a low insoluble substances fraction (<0.15%). The determined acid content was similar to the theoretical content. The physical properties of the chitosan influenced the kinematic viscosity of the salt solutions. The kinematic viscosity decreased when the viscosity-average molecular weights of the chitosan decreased. The properties of chitosan did not significantly impact the pH of the salt solutions. This depended on the pKa of the acid. The chemical and physical properties of the salts can be altered by neutralizing the dichloroacetate solutions to a pH at which no distinct change in clarity occurs.

2

MECHANISM OF FORMATION OF THERMOSENSITIVE CHITOSAN CHLORIDE GELS

100%

Modrzejewska Z., Skwarczyńska A., Maniukiewicz W., Douglas T. E. L.

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2014

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vol. 19

125+134

EN

The studies were carried out to develop the mechanism of chitosan gel formation in the presence of glycerol phosphate GP, taking into account suggestions presented in the literature. The analysis was carried out on the basis of a change in the gel structure after conditioning in water.

3

BIOLOGICAL PROPERTIES OF THERMOSENSITIVE CHITOSAN GELS CONDITIONING IN WATER

100%

Modrzejewska Z., Paluch D., Skwarczyńska A.

Progress on Chemistry and Application of Chitin and its Derivatives

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2015

|

vol. 20

204-212

EN

In this paper the properties of thermosensitive chitosan hydrogels prepared with the use of chitosan salz (chloride and lactate) and -glycerophosphate are presented. Biological studies were carried out on thermogels without conditioning in water and on thermogels after 24 h conditioning in water. Experiments were conducted on a reference cell line L 929 (NCTC clone 929) American Type Culture Collection according to Annex C PN-EN ISO 10993-5

4

Controlled release fertilizers

100%

Lubkowski K., Grzmil B.

Polish Journal of Chemical Technology

|

2007

|

vol. 9

|

issue 4

83-84

EN

The efficiency of nitrogen assimilation by plants is rather low and this is a serious problem in view of environmental protection. Improvement of nitrogen absorption can be carried out through the developing, producing and applying the controlled release fertilizers. Biodegradable chitosan has been proposed as an alternative material in the production of controlled release fertilizers.

5

ELECTROLYTIC METHOD FOR OBTAINING POROUS CHITOSAN STRUCTURES WITH HYDROXYAPATIT

80%

Tylman M., Mucha M.

Progress on Chemistry and Application of Chitin and its Derivatives

|

2011

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vol. 16

5 - 14

EN

The aim of this study was to develop a preparation method of porous chitosan structures, in the electrolysis of the chitosan solution in acetic acid. Chitosan in aqueous acetic acid is a polyelectrolyte. During the constant flow of electric current through this system, pure chitosan begins to accumulate on an anode, in the form of porous hydrogel layers. The addition of hydroxyapatite (HAp) to the electrolyte enhances the process and allows for obtaining spatially arranged complex structures of chitosan.

6

HIERARCHICAL ZEOLITES MODIFIED WITH CHITOSAN – SYNTHESIS AND CHARACTERISATION

80%

Feliczak-Guzik A., Musielak E., Nowak I.

Progress on Chemistry and Application of Chitin and its Derivatives

|

2022

|

vol. 27

54-66

EN

This paper describes the synthesis of hierarchical zeolites based on a commercial FAU zeolite modified with chitosan. Additionally, the amount of silicon source added (tetraethyl orthosilicate) and the type of structuring agent used were modified during synthesis of the materials. The synthesised materials were characterised by the following methods: X-ray diffraction, transmission electron microscopy, scanning electron microscopy, Fourier transform infrared spectroscopy, and low-temperature nitrogen adsorption/ desorption isotherms. The obtained results confirmed the achievement of additional porosity in the synthesised materials. According to the adsorption experiments, the hierarchical zeolite-modified chitosan had a high adsorption capacity of 1.2 cm3 g-1.

7

ADSORPTION STUDIES OF KETOCONAZOLE WITH CHITOSAN

80%

Meler J., Szcześniak M., Pluta J., Grimling B.

|

2014

|

vol. 19

111-117

EN

Combinations of polymers and biopolymers of biologically active compounds in the last period have been the subject of intensive research. The active substance linked to a polymer often has a modified function and sometimes no action. On the other hand, the use of unsuitable polymers may result in a type of mismatch of drug-polymer. The aim of the study was to examine whether the active substance ketoconazole causes incompatibility with dietary supplements containing chitosan. Antifungal drug adsorption phenomenon was investigated by the static method in the concentration range of the single dose using a pharmaceutical model of the gastrointestinal tract. The test results show that the antifungal agent is adsorbed onto the chitosan in the pH ranges used, and the binding ability of the chitosan depends on the variety, or indirectly from the reaction environment. It was observed that the average sorption, depending on the variety of chitosan, was located in the limit from 94% to 100%. The increase of the size of the adsorption of anti-inflammatory drugs on the polymer with increasing pH from 7.6 to 8.0 can be explained by the swelling properties of chitosan, which grow with increasing pH of the environment in the direction of alkaline pH. Thus, the specific surface area and polymer sorption capacity is increased. Based on the above considerations, it can be concluded that, between the test drug and the polymer, there is antagonistic interaction involving the adsorption of the drug of this group on a polymer which is chitosan.

8

CHARACTERISATION OF CHITOSAN AFTER CROSS-LINKING BY TANNIC ACID

80%

Sionkowska A., Kaczmarek B., Lewandowska K.

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2014

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vol. 19

135-138

EN

Chitosan is widely applied in biomedical and cosmetic fields. For this reason, there is a need to modify this biopolymer to achieve new properties of chitosan-based materials. The properties of chitosan can be modified by several cross-linking methods. In this work, we used the chemical cross-linking of chitosan with tannic acid, after which cross-linked chitosan was shaped into a 3D structure by the lyophilisation process. For the material obtained, FTIR-ATR analysis was performed to characterise the structure of cross-linked chitosan. Moreover, mechanical properties and swelling properties were measured for chitosan before and after cross-linking. The results show that several properties of chitosan can be changed after cross-linking by tannic acid. The positions of bands in the FTIR spectra of chitosan were shifted after cross-linking. Mechanical properties were altered for cross-linked chitosan. However, the highest compressive modulus was observed for pure chitosan. The lowest compressive modulus was observed for chitosan cross-linked with 20 wt% of tannic acid. Swelling behaviour also depends on the cross-linking of chitosan. It decreases for chitosan after cross-linking by tannic acid. Overall, the properties of cross-linked chitosan depend on the amount of tannic acid used for modification. This method of cross-linking can be useful for obtaining materials with specific properties.

9

REUSABILITY OF CHITOSAN AND SAWDUST-MODIFIED CHITOSAN FOR ADSORPTION/DESORPTION OF ANIONIC AND CATIONIC DYES

80%

Filipkowska U., Tomasz J.

Progress on Chemistry and Application of Chitin and its Derivatives

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2023

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vol. 28

14-25

EN

We explored the multiple uses of chitosan in the form of beads and beech sawdust immobilised in chitosan to remove anionic (Reactive Yellow 85 and Reactive Blue 5) and cationic (Basic Violet 10 and Basic Green 4) dyes. For both anionic dyes, with the next adsorption/desorption cycle, the amount of dye accumulated in the adsorbent increased, which resulted in a decrease in the desorption efficiency. The number of possible adsorption/desorption cycles was regulated by the occupation of all active sites. We observed the opposite trend for the cationic dyes: the charge accumulated in the adsorbent after both adsorption and desorption decreased with subsequent cycles. Despite the low accumulated charge compared with the total adsorption capacity of the adsorbents, it was impossible to further adsorb and desorb the dye. The results demonstrated that for both adsorbents tested, it was possible to carry out 6–7 adsorption/desorption cycles, but the desorption efficiency decreased with each cycle.

10

EFFECT OF CHITOSAN AND LIPID LAYERS DEPOSITED ONTO POLYETHYLENE TEREPHTHALATE (PET) ON ITS WETTING PROPERTIES

80%

Szafran K., Jurak M., Wiącek A. E.

Progress on Chemistry and Application of Chitin and its Derivatives

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2021

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vol. 26

210-221

EN

The wetting properties of chitosan (Ch) and single 1,2-dipalmitoylsn-glycero-3-phosphocholine (DPPC), cholesterol (Chol) and binary DPPC-Chol layers deposited onto polyethylene terephthalate activated by low-temperature air plasma (PETair) were examined. PET is widely used in tissue engineering, but its low hydrophilicity limits its integration with the surrounding tissues. Ch is a biocompatible polysaccharide, distinguished by its antimicrobial properties, widely distributed in medicine. DPPC and Chol are the major building components of cell membrane, so they can perfectly mimic membrane behaviour during contact with the Ch layer. Monolayers of lipids were deposited onto PETair with or without the Ch layer using the Langmuir-Blodgett technique. The total surface free energy (SFE) and its components changes were calculated from theoretical approaches. Wettability strongly depended on the monolayer composition as well as the Ch layer. The Ch film decreased the contact angle and increased SFE of the PET surface with the lipid monolayers due to specific organisation of molecules within the chitosan scaffold. The most promising combination of surface modification for tissue engineering applications seems to be the PETair/Ch/DPPC-Chol system.

11

APPLICATION OF CHITOSAN IN THE FORMULATION OF DERMATOLOGICAL HYDROGELS PREPARED ON THE BASIS OF MACROMOLECULAR COMPOUNDS

80%

Szcześniak M., Grimling B., Meler J., Karolewicz B.

Progress on Chemistry and Application of Chitin and its Derivatives

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2018

|

vol. 23

179 - 184

EN

The effect of chitosan concentration on the properties of dermatological preparations prepared with 2% methylcellulose and 10% polyvinylpyrrolidone was studied. As the levels of chitosan, propylene glycol-1,2 and glycerol increased, the hardness, consistency and cohesiveness of the hydrophilic gels increased, while the dissipation capacity decreased. Gels based on methylcellulose and chitosan, compared to formulations containing polyvinylpyrrolidone, have a higher rate of loss of volatile compounds, higher pH values for 1,2-propylene glycol formulation and higher texture parameters. The tested hydrogels have good rheological properties, allowing extrusion from the tube and spreading on the skin.

12

Artificial skin composites

80%

Ładniak A.

Annales Universitatis Mariae Curie-Skłodowska, sectio AA – Chemia

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2018

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vol. 73

|

issue 1

EN

Skin injuries are a health problem and can lead to serious, significant deterioration in the quality of life and, consequently, even illness and disability. Therefore, after wounding, immediate regeneration of the tissue is necessary to avoid further complications and pathogenesis. Consequently, many wound healing strategies have been developed, leading to the progress in constructing of multifunctional tissue substitutes for the skin, biomembranes, scaffolds and intelligent dressings. The field of science focusing on the creation of the above-mentioned products is tissue engineering (TE). Its main goal is to find a system that is able to replace or be a model that perfectly mimics the form and function of the skin. Research carried out on such constructs is mainly based on the analysis of mechanical properties (porosity, elasticity), as well as the assessment of the impact of individual components on processes related to the formation of new tissue as cell proliferation and differentiation, proliferation, angiogenesis - through in vivo studies (using animal models: mice, New Zealand rabbits) and in vitro (most often using mouse fibroblasts - L929). Skin constructions may have potential applications as wound dressings or skin substitutes in cases of severe skin damage.

13

β-Galactosidase from Penicillium canescens. Properties and immobilization

80%

Budriene S., Gorochovceva N., Romaskevic T., Yugova L., Miezeliene A., Dienys G., Zubriene A.

Open Chemistry

|

2005

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vol. 3

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issue 1

95-105

EN

β-galactosidase from Penicillium canescens was immobilized on chitosan, sepharose-4B, foamable polyurethane and some other carriers. The highest yield of immobilization (up to 98%) was obtained by using chitosan as a carrier. The optimum pH and temperature were not significantly altered by immobilization. High stability of immobilized β-galactosidase during storage was demonstrated. Efficient lactose saccharification (over 90%) in whey was achieved by using immobilized β-galactosidase.

14

INFLUENCE OF UV-IRRADIATION ON MOLECULAR WEIGHT OF CHITOSAN

80%

Sionkowska A., Płanecka A., Lewandowska K., Kaczmarek B., Szarszewska P.

Progress on Chemistry and Application of Chitin and its Derivatives

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2013

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vol. 18

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issue 18

21-28

EN

In the present paper the results regarding the influence of UV-irradiation with 254 nm wavelength on the molecular weight of chitosan are presented. The concentration of chitosan solution was 0.5%(w/w) in 0.1 M acetic acid. The degree of deacetylation, determined by potentiometric titration in an acidic solution by alkaline, was 81%. Viscosity-average molecular weight of chitosan was determined using an Ubbelohde capillary viscometer. Mark–Houwink equation for the calculation of molecular weight was applied. The results showed that the viscosityaverage molecular weight of chitosan was decreasing with increasing time of exposure to UV-irradiation. Spectroscopic analysis of UV-Vis and FTIR confirmed the photodegradation processes of chitosan. The increasing absorbance in UV-Vis spectra indicated the formation of new chromophoric groups after UV-irradiation of chitosan. Microscopic studies showed changes on the surface of the irradiated films of chitosan and decrease of the surface roughness.

15

IN VIVO STIMULATION OF PERITONEAL CELLS BY CHITOSAN ADMINISTERED IN DRINKING WATER TO MICE

80%

Brodaczewska K., Doligalska M.

Progress on Chemistry and Application of Chitin and its Derivatives

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2012

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vol. 17

111 - 116

EN

The aim of the study was to determine immunostimulant properties of chitosan administered alimentary to BALB/c mice. We observed that chitosan feeding effected in activation of cells from the peritoneal cavity. The cells produced less nitric oxide with simultaneous enhanced activity of arginase and higher expression of receptor for IL-4. What is more, chitosan caused increased number of cells expressing MHC class II. The study confirms that chitosan can stimulate immune system what potentially makes it useful candidate for adjuvant.

16

EFFECT OF CHITOSAN ON THE RHEOLOGICAL PROPERTIES OF HYDROGELS BASED ON SODIUM CARBOXYMETHYLCELLULOSE

80%

Szcześniak M., Grimling B., Pluta J., Meler J.

Progress on Chemistry and Application of Chitin and its Derivatives

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2015

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vol. 20

254-259

EN

The aim of the study was to evaluate the effect of changing the concentrations of chitosan on the rheological properties of the obtained formulation. Hydrogels were prepared with 1% hydrocortisone containing 4% sodium carboxymethylcellulose with the addition of chitosan, propylene glycol-1,2 or polyethylene glycol 400 and glycerol or paraffin. The concentration of chitosan and excipients affects the rheological properties of gels and the pharmaceutical availability of hydrocortisone. Increasing the concentration of chitosan have influence on increasing the viscosity, hardness, and cohesiveness of the tested gels.

17

CHARACTERIZATION OF MIXED LANGMUIR MONOLAYERS OF CYCLOSPORINE A WITH THE PHOSPHOLIPID DPPC AT THE CHITOSAN SUBPHASE

80%

Woźniak K., Jurak M., Wiącek A. E.

Progress on Chemistry and Application of Chitin and its Derivatives

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2020

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vol. 25

227 - 235

EN

The properties of one-component and mixed monolayers of phospholipid 1,2–dipalmitoyl–sn–glycero–3–phosphocholine (DPPC) and polypeptide cyclosporine A (CsA) on the chitosan subphase were studied. DPPC is the main component that builds biological membranes, and CsA is an immunosuppressive drug typically used in medicine to prevent transplant rejections. The stability and reversibility of compression of these insoluble monolayers in the presence of chitosan (Ch) were examined by the Langmuir technique. The stability of the monolayers depended on the monolayer composition as well as the initial pressure (π0) of the relaxation process. The smallest changes in the relative pressure as a function of time were obtained at π0 = 10 mN/m. During compression–decompression cycles, the effect of chitosan was noticeable and caused isotherm shifts.

18

SYNTHESIS OF NANOCOMPOSITE CHITOSAN-TiO2 AND ITS APPLICATION AS PHOTODEGRADATION AGENT OF METHILEN BLUE IN AQUEOUS MEDIUM

80%

Mohadi R., Kurniawan C., Yuliasari N., Hidayati N., Lesbani A.

Progress on Chemistry and Application of Chitin and its Derivatives

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2015

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vol. 20

213-221

EN

Synthesis of nanocomposite chitosan-TiO2 have been done. Nanocomposite made of chitosan was isolated from crab shell namely α-chitosan and squid pens as β-chitosan. Nanocomposite was synthesized by combining the function of chitosan as supporting material with TiO2 particle that have high photocatalytic activity. The nanocomposite characterized by FTIR and SEM/EDX analysis show the functional groups of chitosan and and also surface morphology of nanocomposite chitosan-TiO2. The FTIR spectra shows adsorption band of O-Ti-O at 677-695 cm-1, and characteristic adsorption band of chitosan at wavenumbers 1600 cm-1 for -NH2 and 3400 cm-1 for -OH. From SEM/EDX analysis can be seen that TiO2 has been distributed evenly on surface of chitosan. The nanocomposite was applied for photodegradation of methylene blue in aqueous medium on UV light radiation. The optimum percent photodegradation at wavelength 660 nm by the nanocomposite α-chitosan-TiO2 and β-chitosan-TiO2 are 59,48% and 59,82%, respectively.

19

INFLUENCE OF NANOSILVER ON THERMAL STABILITY OF CHITOSAN

80%

Białas S., Mucha M.

Progress on Chemistry and Application of Chitin and its Derivatives

|

2013

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vol. 18

|

issue 18

85-92

EN

Nanoadditives for polymers have many valuable features: e.g. the ability to change the properties of polymers: mechanical strength, stability and heat resistance and resistance to radiation. These properties make them an interest in recent years. Studies of polymer composites with nanoadditives leads to discovering more, unique types of nanoadditive interactions on a structure and properties of the polymer. One of the most widely used nanoadditive is nanosilver, which have antibacterial and antifungal properties. An important aspect is thus to investigate the effect of this additive on thermal stability of the polymer composite. The aim of this study was to investigate the effect of nanosilver on the thermal stability and properties of chitosan. Chitosan composites with nanosilver in the form of films with a thickness of 10-30um and the content of silver 0.5 and 1% was obtained by casting. In order to study the thermal stability samples were subjected to a temperature of 120°C (time 0-90h). Studies on influence of nanosilver on the thermal stability of the polymer was performed using infrared spectroscopy (FTIR). This allows to observe changes in the chemical structure of polymer. The changes in the major functional groups was observed: 1420cm-1(bending vibration of -C-H group), 1577cm-1 (bending vibrations of the amine group-NH2), 1655cm-1 (vibrations of C=O in amide group). Mechanical strength test of chitosan composites subjected to high temperature was also performed. Tensile tests (using the Instron 5325 apparatus) were conducted to determine changes in values of Young's modulus, maximum stress and elongation at break. The study showed an effect of the presence of nanosilver on the structural and mechanical properties of chitosan. Nanosilver improves the thermal stability of studied functional groups of chitosan.

20

THE STUDY OF PHYSICOCHEMICAL PROPERTIES OF SOLID DISPERSIONS OF IBUPROFEN IN THE PRESENCE OF CHITOSAN

80%

Grimling B., Meler J., Szcześniak M., Pluta J., Górniak A.

Progress on Chemistry and Application of Chitin and its Derivatives

|

2015

|

vol. 20

64-72

EN

The aim of the present study was to increase the solubility of ibuprofen. Among the methods to increase the solubility selected solid dispersions of the drug with the polymer. Chitosan was used as the polymer. Solid dispersion obtained. Ibuprofen was incorporated into the chitosan type 652 with molar masse chitosan Mη = 429 kDa. Solid dispersions were prepared by using different ratios of ibuprofen and chitosan (1:9. 3:7 and 5:5). Formulations were tested dissolution rate of the ibuprofen. The highest dissolution of ibuprofen, amounting to 12.59%, was observed after 60 minutes from solid dispersion prepared by the evaporation method and 12.18% from physical mixtures with drug-polymer weight ratio 1:9 in the presence chitosan. The solubility of the drug improved more than 60-fold. XRPD analysis indicates the presence of the ibuprofen in amorphous form in the solid dispersion obtained by the modified solvent evaporation.

Refine search results

Chitosan dichloro acetic acid salts

MECHANISM OF FORMATION OF THERMOSENSITIVE CHITOSAN CHLORIDE GELS

BIOLOGICAL PROPERTIES OF THERMOSENSITIVE CHITOSAN GELS CONDITIONING IN WATER

Controlled release fertilizers

ELECTROLYTIC METHOD FOR OBTAINING POROUS CHITOSAN STRUCTURES WITH HYDROXYAPATIT

HIERARCHICAL ZEOLITES MODIFIED WITH CHITOSAN – SYNTHESIS AND CHARACTERISATION

ADSORPTION STUDIES OF KETOCONAZOLE WITH CHITOSAN

CHARACTERISATION OF CHITOSAN AFTER CROSS-LINKING BY TANNIC ACID

REUSABILITY OF CHITOSAN AND SAWDUST-MODIFIED CHITOSAN FOR ADSORPTION/DESORPTION OF ANIONIC AND CATIONIC DYES

EFFECT OF CHITOSAN AND LIPID LAYERS DEPOSITED ONTO POLYETHYLENE TEREPHTHALATE (PET) ON ITS WETTING PROPERTIES

APPLICATION OF CHITOSAN IN THE FORMULATION OF DERMATOLOGICAL HYDROGELS PREPARED ON THE BASIS OF MACROMOLECULAR COMPOUNDS

Artificial skin composites

β-Galactosidase from Penicillium canescens. Properties and immobilization

INFLUENCE OF UV-IRRADIATION ON MOLECULAR WEIGHT OF CHITOSAN

IN VIVO STIMULATION OF PERITONEAL CELLS BY CHITOSAN ADMINISTERED IN DRINKING WATER TO MICE

EFFECT OF CHITOSAN ON THE RHEOLOGICAL PROPERTIES OF HYDROGELS BASED ON SODIUM CARBOXYMETHYLCELLULOSE

CHARACTERIZATION OF MIXED LANGMUIR MONOLAYERS OF CYCLOSPORINE A WITH THE PHOSPHOLIPID DPPC AT THE CHITOSAN SUBPHASE

SYNTHESIS OF NANOCOMPOSITE CHITOSAN-TiO2 AND ITS APPLICATION AS PHOTODEGRADATION AGENT OF METHILEN BLUE IN AQUEOUS MEDIUM

INFLUENCE OF NANOSILVER ON THERMAL STABILITY OF CHITOSAN

THE STUDY OF PHYSICOCHEMICAL PROPERTIES OF SOLID DISPERSIONS OF IBUPROFEN IN THE PRESENCE OF CHITOSAN