Carboxymethylcellulose Sodium Salt Research Articles

Terminal settling velocity of the binary solid mixture in the non-Newtonian pseudoplastic liquid system

Particle settling in a non-Newtonian pseudoplastic liquid has gained interest in various industrial applications, including chemical, petroleum, food and pharmaceutical industries. Terminal settling velocities (TVS) of non-spherical particles of binary systems in non-Newtonian viscous pseudoplastic shear thinning solutions were investigated experimentally. An aqueous solution of the sodium salt of carboxymethyl cellulose (SCMC) differing in the concentration of (0.4–0.8) kg/m3 was used as the liquid phase in two different size fluidized bed columns. TSV of the binary solid mixture increases with particle size and decreases with SCMC concentration. The following empirical correlation has been developed which showed an average relative error is 11.41% against 64.98% (minimum) by the earlier correction. Bio-inspired ANNs integrated with GA (Genetic Algorithm) develop a generalized model for estimating settling velocity with an average relative error of 6.9%.

Studying the Efficacy of Local Hemostatic Agents In Vivo

Introduction: In modern clinical practice, there is no common and effective hemostatic agent for solid organs of the abdomen. Local agents such as hemostatic sponges, membranes, powders seem promising. The main advantages of hemostatic powders include relatively high efficacy, portability, versatility, as well as simplicity and low cost of manufacturing.Objective: To study the hemostatic efficacy of hemostatic powders’ samples based on the sodium salt of carboxymethylcellulose (Na-CMC) in an acute in vivo experiment.Materials and methods: The study was based at Kursk State Medical University. Fifty male Wistar rats (weighing 220-239 g) were selected as test animals. They were evenly divided into 5 groups: ARISTA AH, Cutanplast Powder, and Na-CMC hemostatic powders with 3 different dynamic viscosities: low (50-200 cP), medium (400-800 cP) and high (1500-3000 cP). Under general inhalation anesthesia, median laparotomy was performed in Wistar rats, the middle lobe of the liver was removed into the wound, and then marginal tangential resection was performed. We applied hemostatic powders of each group to the resulting wound, and then estimated the bleeding time and the volume of blood loss. We used the Mann-Whitney test (P ≤ .05) to assess the statistical significance of differences between the study groups.Results: We recorded the minimum bleeding time and the smallest volume of blood loss for the samples based on the Na-CMC and found no statistically significant differences between the viscosities groups.Conclusions: With Na-CMC hemostatic powder the bleeding time and the volume of blood loss were reduced by 3.6 and 2.2 times, respectively, comparing to the control group. These results were considered statistically significant (P ≤ .05).

FORMATION OF SILVER-CONTAINING FILMS BASED ON POLYELECTROLYTE COMPLEXES BY SPUTTERING DEPOSITION AND THEIR ANTIMICROBIAL AND ANTIVIRAL ACTIVITY

Silver-containing film materials are formed by vacuum sputtering of silver nanoparticles on the surface of polyelectrolyte complexes based on chitosan and sodium salt of carboxymethylcellulose (pectin). The obtained samples were characterized by the methods of wide-angle X-ray scattering and transmission electron microscopy, and their antimicrobial, antiviral and cytotoxic properties were also investigated. The presence of metallic silver on the surface of polyelectrolyte complexes was confirmed by the method of wide-angle X-ray diffraction. It was established that upon sputtering of silver, a ~200 nm thick layer is formed within 5 minutes. It was shown that Na-CMC–Ag–chitosan and pectin–Ag–chitosan samples, formed by silver sputtering, exhibit antimicrobial activity against test cultures of S. aureus, E. coli, P. aeruginosa, and C. albicans. Antiviral activity of samples against influenza A virus and herpes simplex virus type 1 was also established. The obtained samples were not cytotoxic, did not inhibit the viability of MDCK and BHK cell cultures.

Feasibility of intranasal delivery of thin-film freeze-dried, mucoadhesive vaccine powders

Intranasal vaccination by directly applying a vaccine dry powder is appealing. However, a method that can be used to transform a vaccine from a liquid to a dry powder and a device that can be used to administer the powder to the desired region(s) of the nasal cavity are critical for successful intranasal vaccination. In the present study, using a model vaccine that contains liposomal monophosphoryl lipid A and QS-21 adjuvant (AdjLMQ) and ovalbumin (OVA) as a model antigen, it was shown that thin-film freeze-drying can be applied to convert the liquid vaccine containing sucrose at a sucrose to lipid ratio of 15:1 (w/w) into dry powders, in the presence or absence of carboxymethyl cellulose sodium salt (CMC) as a mucoadhesive agent. Ultimately, the thin-film freeze-dried AdjLMQ/OVA vaccine powder containing 1.9% (w/w) of CMC (i.e., TFF AdjLMQ/OVA/CMC1.9% powder) was selected for additional evaluation because the TFF AdjLMQ/OVA/CMC1.9% powder was mucoadhesive and maintained the integrity of the antigen and the physical properties of the vaccine. Compared to the TFF AdjLMQ/OVA powder that did not contain CMC, the TFF AdjLMQ/OVA/CMC1.9% powder had a lower moisture content and a higher glass transition temperature. In addition, the TFF AdjLMQ/OVA/CMC1.9% thin films were relatively thicker than the TFF AdjLMQ/OVA thin films without CMC. When sprayed with Aptar Pharma’s Unidose Powder Nasal Spray System (UDSP), the TFF AdjLMQ/OVA powder and the TFF AdjLMQ/OVA/CMC1.9% powder generated similar particle size distribution curves, spray patterns, and plume geometries. Importantly, after the TFF AdjLMQ/OVA/CMC1.9% powder was sprayed with the UDSP nasal device, the integrity of the OVA antigen and the AdjLMQ liposomes did not change. Finally, a Taguchi L4 orthogonal array was applied to identify the optimal parameters for using the UDSP device to deliver the TFF AdjLMQ/OVA/CMC1.9% powder to the middle and lower turbinate and the nasopharynx regions in both adult and child nasal replica casts. Results from this study showed that it is feasible to apply the thin-film freeze-drying technology to transform a nasal vaccine candidate from liquid to a dry powder and then use the UDSP nasal device to deliver the vaccine powder to the desired regions in the nasal cavity for intranasal vaccination.

Use of bacterial cellulose in paper document restoration

Показана эффективность применения суспензии бактериальной целлюлозы Komagataeibacter (Gluconacetobacter) rhaeticus при реставрации документов на бумаге аэродинамическим способом. Одной из проблем при реставрации документов на бумаге методом восполнения утраченных частей документа является прочность шва между реставрируемым документом и восполняющей частью. Для повышения прочности шва документ по контуру утрат обрабатывают связующими - растворами натриевой соли карбоксиметилцеллюлозы или крахмала. В данном исследовании при реставрации методом аэродинамического формования в качестве связующего была применена суспензия бактериальной целлюлозы Komagataeibacter (Gluconacetobacter) rhaeticus. Для создания прочного соединительного шва между реставрируемым документом и восполняющим волокнистым слоем по контуру утраты документа наносили суспензию бактериальной целлюлозы концентрацией 1,0 ± 0,1% масс., предварительно подготовленную в дезинтеграторе. Применение бактериальной целлюлозы в качестве связующего при аэродинамическом способе реставрации привело к повышению прочности сформованного шва в 1,5-2 раза, по сравнению с применением в качестве связующего растворов крахмала и натриевой соли карбоксиметилцеллюлозы. Искусственное тепло-влажное старение документа после реставрации в течение 12 суток показало, что прочность шва снижается после первых трех суток старения на 32% и затем стабилизируется. Это позволяет прогнозировать хорошую сохранность отреставрированного документа в процессе дальнейшего архивного хранения и пользования. С помощью программного комплекса, предназначенного для исследования памятников письменности путем анализа их цифровых изображений «Vestigium» показано, что рельеф поверхности листов документа после реставрации становится более сглаженным, что снижает возможность глубокого проникновения пыли в структуру листа и повышает срок использования документа. The effectiveness of the bacterial cellulose suspension Komagataeibacter (Gluconacetobacter) rhaeticus in the restoration of documents on paper using the aerodynamic method is shown. One of the problems in document restoration on paper using the method of replacing lost parts of a document is the strength of the seam between the document to be restored and the replacing part. To increase the strength of the seam the document is treated with binders - solutions of sodium salt of carboxymethylcellulose or starch on the contour of the loss. In this study, a suspension of bacterial cellulose Komagataeibacter (Gluconacetobacter) rhaeticus was used as a binder for the restoration by aerodynamic molding. In order to create a strong bonding seam between the restored document and the replenishing fibrous layer, a suspension of bacterial cellulose with a concentration of 1.0 ± 0.1 wt. %, previously prepared in a disintegrator, was applied along the contour of the lost document. The use of bacterial cellulose as a binder in the aerodynamic method of restoration led to an increase in the strength of the formed seam by 1.5-2.0 times compared to the use of starch solutions and sodium salt of carboxymethylcellulose as a binder. Artificial heat-moist aging of the document after restoration for 12 days showed that the suture strength decreased after the first three days of aging by 32% and then stabilized. This makes it possible to predict good preservation of the restored document during further archival storage and use. With the help of «Vestigium» software designed to study the monuments of writing by analyzing their digital images, it is shown that the relief of the document sheets surface after restoration becomes smoother, which reduces the possibility of deep penetration of dust into the sheet structure and increases the life of the document.

Performance evaluation of guar gum and conventional binders based fire‐extinguishing aerosol‐forming composites

AbstractPyrotechnic‐based firefighting systems have been found to be effective in a wide variety of firefighting applications. Binders in pyrotechnic mixtures play a significant role as they consolidate the ingredients, provide excellent mechanical strength and increase the storage life. The rise in health and environmental safety concerns in recent years has directed our research towards natural binder systems of biological origins. Therefore, in this work, galactomannan, also called guar gum, was comparatively investigated against four different types of conventional binders, phenol–formaldehyde resin, ethyl cellulose, hydroxyethyl cellulose and carboxymethyl cellulose sodium salt, which are being used in aerosol‐forming pyrotechnic mixtures for firefighting application. It was found that the nature of the binder in an amount of 3% by weight significantly influences the combustion behaviour, fire suppression performance, mechanical and thermal characteristics of gallic acid–KNO3–KClO3 tertiary aerosol‐forming pyrotechnic mixture for fire fighting application. The safety and performance characteristics of these formulations were evaluated by conducting analyses specific to pyrotechnic formulations, that is, burn rate measurement, heat of combustion, TGA/DSC thermal analysis, hygroscopic study, compression test and n‐heptane pool fire suppression test. It can be inferred from the values obtained from these analyses that guar gum is a preferred binder to the other four‐binder systems for the gallic acid–KNO3–KClO3 pyrotechnic mixture.

Study on the interaction mechanism between ficin and a graft copolymer of carboxymethyl cellulose sodium salt and N-vinylimidazole using moleculardocking, fourier-transform infrared spectroscopy and raman spectroscopy

Flexible molecular docking, Fourier-transform infrared spectroscopy (FTIR) and Raman spectroscopy were used to investigate the interaction mechanism between ficin and a graft copolymer of carboxymethyl cellulose sodium salt and N-vinylimidazole. Functional groups and fragments of the graft copolymer as well as amino acid residues that form primary structure of enzyme and participate in interactions between ficin and a graft copolymer are identified. It is shown that Raman spectroscopy yields more complete information about graft copolymer fragments interacting with the protein than that FTIR can provide. It is found that the amino acid residues that form the active site of ficin are involved in the formation of hydrogen bonds and hydrophobic interactions with the graft copolymer leading to an increase in the proteolytic activity of the conjugated enzyme.

Study of the Mechanism of Interaction of Ficin with a Graft Copolymer of Carboxymethyl Cellulose Sodium Salt and N-vinylimidazole Using Molecular Docking, as Well as Infrared and Raman Spectroscopy

Study of the Mechanism of Interaction of Ficin with a Graft Copolymer of Carboxymethyl Cellulose Sodium Salt and N-vinylimidazole Using Molecular Docking, as Well as Infrared and Raman Spectroscopy

Single-Electrode Triboelectric Nanogenerators Based on Ionic Conductive Hydrogel for Mechanical Energy Harvester and Smart Touch Sensor Applications

Recent advancements in wearable electronic technology demand advanced power sources to be flexible, deformable, durable, and sustainable. An ionic-solution-modified conductive hydrogel-based triboelectric nanogenerator (TENG) has advantages in wearable devices. However, fabricating a conductive hydrogel with better mechanical and electrical properties is still a challenge. Herein, a simple approach is developed to insert ion-rich pores inside the hydrogel, followed by ionic solution soaking. The suggested ionic conductive hydrogel is obtained by cross-linking the polyvinyl alcohol (PVA) hydrogel and carboxymethyl cellulose sodium salt (CMC), followed by soaking in the ionic solution. Furthermore, a flexible and shape-adaptable single-electrode TENG (S-TENG) is fabricated by combinations of ionic-solution-modified dual-cross-linked CMC/PVA hydrogel and silicone rubber. Additionally, the effects of the CMC concentration, type of ionic solution, and concentration of optimized ionic solutions on the hydrogel properties and S-TENG output performance are studied systematically. The well-dispersed CMC- and PVA-based hydrogel provides ion-rich pores with high ion migration, leading to enhanced conductivity. The fabricated S-TENG delivers maximum output performance in terms of voltage, current, and charge density of ∼584 V, 25 μA, and 120 μC/m2, respectively. The rectified S-TENG-generated energy is used to charge capacitors and to power a portable electronic display. In addition to energy harvesting, the S-TENG is successfully demonstrated as a touch sensor that can automatically control the light and the speaker based on human motions. This investigation provides a deep insight into the influence of the hydrogel on the device performance and gives a guidance for designing and fabrication of highly flexible and stretchable TENGs.

Preparation of Cellulose Hydrogels and Hydrogel Nanocomposites Reinforced by Crystalline Cellulose Nanofibers (CNFs) as a Water Reservoir for Agriculture Use

An effective strategy for the management of available water and fertilizers is imperative to improve agricultural production and food quality, including releasing them sustainably to the soil and plants. Polymeric hydrogels with three-dimensional (3D) networks can absorb ample water and soluble fertilizers without network dissolution. Subsequently, the absorbed water and fertilizers can be released to arid and semi-arid agricultural land to furnish enough moisture and nutrients for plant growth. In this study, carboxymethyl cellulose sodium salt (NaCMC)- and hydroxyethyl cellulose (HEC)-based hydrogels have been synthesized using citric acid (CA) as a crosslinker. The Fourier transform infrared (FTIR) spectroscopy study revealed the formation of hydrogels with porous structures depicted by field emission scanning electron microscopy images. The prepared hydrogels have shown a remarkable swelling ratio of ∼1070% for the hydrogel prepared using NaCMC/HEC: 2/1 and ∼840% for NaCMC/HEC: 3/1 and a reduction in the swelling ratio with increasing crosslinking density. Moreover, crystalline (shown by X-ray diffraction) cellulose nanofibers (CNFs: ∼600 nm), prepared by acid (H2SO4) hydrolysis of cotton fibers, have been used to prepare hydrogel nanocomposites. The evaluation of hydrogel nanocomposites’ mechanical properties (universal testing matching test) depicted an improved tensile strength (16.27 MPa using 0.7% CNFs) compared to that of the hydrogel without CNFs. The soil burial test for biodegradation study of prepared hydrogels revealed soil degradation of hydrogel, confirmed by FTIR analysis and visual appearance. The current study provides comprehensive data establishing the potential of hydrogels for agriculture applications.

Dual Origin of Viscoelasticity in Polymer-Carbon Black Hydrogels: A Rheometry and Electrical Spectroscopy Study

Nanocomposites formed by mixing nanoparticles and polymers offer a limitless creative space for the design of functional advanced materials with a broad range of applications in materials and biological sciences. Here we focus on aqueous dispersions of hydrophobic colloidal soot particles, namely carbon black (CB) dispersed with a sodium salt of carboxymethylcellulose (CMC), a food additive known as cellulose gum that bears hydrophobic groups, which are liable to bind physically to CB particles. Varying the relative content of CB nanoparticles and cellulose gum allows us to explore a rich phase diagram that includes a gel phase. We investigate this hydrogel using rheometry and electrochemical impedance spectroscopy. CB-CMC hydrogels display two radically different types of mechanical behaviors that are separated by a critical CMC-to-CB mass ratio $r_c$. For $r<r_c$, i.e., for low CMC concentration, the gel is electrically conductive and shows a glassy-like viscoelastic spectrum, pointing to a microstructure composed of a percolated network of CB nanoparticles decorated by CMC. In contrast, gels with CMC concentration larger than $r_c$ are non-conductive, indicating that the CB nanoparticles are dispersed in the cellulose gum matrix as isolated clusters, and act as physical crosslinkers of the CMC network, hence providing mechanical rigidity to the composite. Moreover, in the concentration range, $r>r_c$ CB-CMC gels display a power-law viscoelastic spectrum that depends strongly on the CMC concentration. These relaxation spectra can be rescaled onto a master curve that exhibits a power-law scaling in the high-frequency limit, with an exponent that follows Zimm theory, showing that CMC plays a key role in the gel viscoelastic properties for $r>r_c$. Our results offer a characterization of CB-CMC dispersions that will be useful for designing nanocomposites based on hydrophobic interactions.

Design and in vitro effectiveness evaluation of Echium amoenum extract loaded in bioadhesive phospholipid vesicles tailored for mucosal delivery

The Echium amoenum Fisch. and C.A. Mey. (E. amoenum) is an herb native from Iranian shrub, and its blue-violet flowers are traditionally used as medical plants. In the present study, an antioxidant phytocomplex was extracted from the flowers of E. amoenum by ultrasounds-assisted hydroalcoholic maceration. The main components, contained in the extract, have been detected using HPLC-DAD, and rosmarinic acid was found to be the most abundant. The antioxidant power of the extract along with the phenolic content were measured using colorimetric assays. The extract was loaded in liposomes, which were enriched adding different bioadhesive polymers (i.e., mucin, xanthan gum and carboxymethyl cellulose sodium salt) individually or in combination. The main physico-chemical properties (i.e. size, size distribution, surface charge) of the prepared vesicles were measured as well as their stability on storage. The viscosity of dispersion and the ability of vesicles to interact with mucus were evaluated measuring their stability in a mucin dispersion and mobility in a mucin film. The biocompatibility and the ability of the formulations to protect keratinocytes from damages caused by hydrogen peroxide and to promote the cell migration were measured in vitro.

Carboxymethyl Cellulose-Based Polymers as Promising Matrices for Ficin Immobilization.

The present work is devoted to research on the interaction between carboxymethyl cellulose sodium salt and its derivatives (graft copolymer of carboxymethyl cellulose sodium salt and N,N-dimethyl aminoethyl methacrylate) with cysteine protease (ficin). The interaction was studied by FTIR and by flexible molecular docking, which have shown the conjugates' formation with both matrices. The proteolytic activity assay performed with azocasein demonstrated that the specific activities of all immobilized ficin samples are higher in comparison with those of the native enzyme. This is due to the modulation of the conformation of ficin globule and of the enzyme active site by weak physical interactions involving catalytically valuable amino acids. The results obtained can extend the practical use of ficin in biomedicine and biotechnology.

Physicochemical mechanism of BSA, Hb, and dsDNA biomacromolecules with aq-NaCMC at 298.15–310.15 K interfaced with UV–vis fluorescence circular dichroism spectroscopy and in-silico for interacting activities

The 0.2–0.8mg% @ 0.2 mg% bovine serum albumin (BSA 66), hemoglobin (Hb 64.5), and double stranded deoxyribonucleic acid (dsDNA 130 kDa) with water and 0.25, 0.50, and 1.00 g% aqueous carboxymethyl cellulose sodium salt (NaCMC) thermodynamically, kinetically, and tentropically stable homogeneous solutions via resonating energy transfer were designed. Density (ρ), viscosity (η), surface tension (γ), friccohesity (σ), Gibbs free energy (ΔGb), chemical potential (μ), frictional volume (ϕ), apparent molar volume (V2), hydrodynamic radius (Rh), and isentropic compressibility (ksϕ) at 298.15, 304.15, and 310.15 K were studied. UV–Vis spectrophotometry, fluorescence spectroscopy, circular dichroism (CD), MALDI TOF, and in-silico study via reorientational activities have elucidated structural recognition. The ρ, η, γ, σ, ΔGb, μ, V2, ϕ, Rh, and ksϕ physicochemical properties (PCPs) have studied the interacting activities of salt bridges (peptide bonds) of proteins and base pairs (adenine, thymine, cytosine, guanine) of dsDNA on developing nanohydration sphere (NHS) with water and 0.25, 0.50, and 1.00 g% aq-NaCMC. Regression constants of PCPs have elaborated the interacting mechanism of internal linkages of BSA, Hb, and dsDNA for solubilizing them without unfolding assisted by glycosidic bonds of glucopyranose units of NaCMC. Magnitudes of regression constants analyse the inner salt bridges, electrostatic dipoles, and hydrogen bonds (HB) to interact with H2O dipoles and NaCMC affecting solubilization of biomolecules (biomols) in areas of biochemical, biophysical, bioengineering, tissue, and genetic engineering. PCPs, UV–Vis, fluorescence, CD, and in-silico study analyse their structurally interacting abilities with NaCMC via respective NHS to be extended to pharmaceutical and cosmetic processes by minimizing quantum energy barrier (QEB) as Newtonian behaviour of structural sensors.

Removal of dimethylarsinate from water by robust NU-1000 aerogels: Impact of the aerogel materials

This study compared the effect of three matrices on the dimethylarsinate (DMA) removal from water to NU-1000 (zirconium-based metal–organic framework, Zr-MOF) hybrid aerogels. The porous MOF hybrid aerogels were prepared by grafting NU-1000 into green matrices, i.e., agarose (AG), sodium alginate (SA), and carboxymethyl cellulose (CMC) sodium salt. The adsorption data of DMA can be well described by the pseudo-second-order kinetic model and the Freundlich isotherm model. The maximum adsorption capacity of the NU-1000@AG hybrid aerogel for DMA (119.63 mg/g) was higher than the other two hybrid aerogels due to the negligible interference of AG on the active adsorption sites in NU-1000. However, the functional groups in NU-1000@CMC hybrid aerogel and NU-1000@SA hybrid aerogel occupied the Zr adsorption sites during the cross-linked process and decreased their adsorption capacities. The NU-1000@AG hybrid aerogel demonstrated application potential for removing DMA in a fixed-column dynamic adsorption process. Furthermore, the NU-1000 hybrid aerogels exhibited excellent regeneration performance and ease of solid–liquid separation. The characteristics of various matrices may offer diversified facile and viable strategies for fabricating a blocky adsorbent with superior stability and solid–liquid separation efficiency for water treatment, overcoming the disadvantages of MOF powder and ensuring maximum effectiveness of adsorbent components.

“In Situ” Formation of Zn Anode from Bimetallic Cu-Zn Alloy (Brass) for Dendrite-Free Operation of Zn-Air Rechargeable Battery

In this article, the performance of brass electrode was investigated in a Zn-air (charcoal-based cathode) rechargeable battery. The construction of the battery was carried out with biodegradable materials, namely a cotton cloth diaphragm and carboxymethyl cellulose sodium salt (CMC-Na) viscosity modifier, while the battery skeleton was printed by 3D printing technology. The brass acted as a collector and a preferable surface for the metallic Zn deposition on the brass anode surface. The electrochemical behavior of the brass anode was investigated by cyclic voltammetry (CV). Cyclic performance tests were carried out, which showed stable cell operation even in the presence or absence of additives up to more than 100 cycles. Furthermore, high energy (Eeff) and Coulomb (Ceff) efficiencies, 80% (Eeff), 95% (Ceff), 75% (Eeff), and 95% (Ceff) were obtained, respectively. The Shepherd model was applied to describe the discharging processes of the Zn-air battery containing brass as anode in the presence of additive-free electrolyte or electrolyte with CMC-Na salt additive. It was found that the Shepherd equation described only approximately the resulting discharge curves. In order to attain a more precise mathematical description, stretched exponential function was implemented into the last term of the Shepherd equation. The need for such a correction shows the complexity of the electrochemical processes occurring in these systems. In addition, the surface of the brass anode was also investigated by scanning electron microscopy (SEM) and the composition of the brass alloys was determined by X-ray fluorescence spectroscopy (XRF). Importantly, the formation of dendritic deposition was successfully suppressed and a smooth and uniform surface was obtained after the cycling tests.

Efficiency of accelerated electron beam sterilization of a hydrogel for 3D cultivation of mesenchymal multipotent cells

Background. Hydrogels are promising for use in tissue engineering for the restoration and regeneration of various tissues, since they are able to perform the functions of bulk scaffolds, providing the formation of 3D cell structures. Population of such scaffolds with autologous or heterogeneous mesenchymal multipotent stromal cells in vitro makes it possible to localize these cells in the area of target tissues after implantation in a patient. One of the difficult tasks is the choice of the method and mode of sterilization of the hydrogel, which does not change its properties.Aim. Study of the effectiveness of hydrogel sterilization by an accelerated electron beam in various modes, changes in the structure and biocompatibility of the scaffold, to assess the prospects for its use for medical purposes, including as a platform for mesenchymal stromal cells.Materials and methods. We used a hydrogel based on 4 % solutions of sodium alginate and sodium salt of carboxymethyl cellulose, cross-linked with calcium chloride, which was developed, obtained and provided for our research by the team of the Research and Educational Center for Biomedical Engineering of the National University of Science and Technology “MISIS”. Hydrogel samples loaded with Escherichia coli, Lactobacillus acidophilus, Saccharomyces cerevisiae were subjected to electron beam treatment in the range of 5–100 kGy. After electron beam treatment of hydrogel, the presence of living microorganisms and its structure were evaluated by IR-Fourier spectroscopy, as well as the phenotype and formation of 3D structures by mesenchymal multipotent cells.Results. It was found that the treatment of hydrogels with an electron beam at a mode of 25 kGy ensures the death of microorganisms, but does not destroy the structure of the hydrogel and does not inhibit the ability to form capillary-like structures by mesenchymal multipotent cells.Conclusion. Treatment with an accelerated electron beam at a 25 kGy can be used to sterilize hydrogels to obtain bulk scaffolds for cell engineering implants.

INFLUENCE OF CARBOXYMETHYLCELLULOSE SODIUM SALT ON THE PROTECTIVE PROPERTIES OF GELS WITH CHITOSAN FOR THE OESOPHAGEAL MUCOSA

Gastro-oesophageal reflux disease is a serious social problem that affects every sphere of life. The quality of life of people with this disease is reduced due to the presence of troublesome symptoms, which translates into reduced work efficiency and vitality. The major problem is acidic gastro-oesophageal reflux. This study was undertaken to examine whether hydrogels prevent irritation of the oesophageal mucosa. The aim was to investigate the influence of chitosan and carboxymethylcellulose sodium salt on the protective properties of prepared gels in the treatment of acid reflux. The addition of chitosan to all tested gels increased their pH and dynamic viscosity. Preparations containing 0.3% carboxymethylcellulose sodium salt showed the highest pH. The texture tests showed the effect of carboxymethylcellulose sodium salt concentration on the adhesion work of the tested gels. These gels could be used in the treatment of advanced acid reflux

Curcumin-Loaded Microspheres Are Effective in Preventing Oxidative Stress and Intestinal Inflammatory Abnormalities in Experimental Ulcerative Colitis in Rats.

Curcumin’s role in the treatment of ulcerative colitis (UC) has been proven by numerous studies, but its preventive administration, with the aim of reducing the remission episodes that are characteristic of this disease, must be further investigated. This study investigates the effects of a novel curcumin-loaded polymeric microparticulate oral-drug-delivery system for colon targeting (Col-CUR-MPs) in an experimental model of UC. Male Wistar rats (n = 40) were divided into five groups (n = 8), which were treated daily by oral gavage for seven days with a 2% aqueous solution of carboxymethylcellulose sodium salt (CMCNa) (healthy and disease control), free curcumin powder (reference), Col-CUR-MPs (test) and prednisolone (reference) prior to UC induction by the intrarectal administration of acetic acid (AA), followed by animal sacrification and blood and colonic samples’ collection on the eighth day. Col-CUR-MPs exhibited an important preventive effect in the severity degree of oxidative stress that resulted following AA intrarectal administration, which was proved by the highest catalase (CAT) and total antioxidant capacity (TAC) levels and the lowest nitrites/nitrates (NOx), total oxidative status (TOS) and oxidative stress index (OSI) levels. Biochemical parameter analysis was supported by histopathological assessment, confirming the significant anti-inflammatory and antioxidant effects of this novel colon-specific delivery system in AA-induced rat models of UC. Thus, this study offers encouraging perspectives regarding the preventive administration of curcumin in the form of a drug delivery system for colon targeting.

Experimental evaluation of structure formation in solutions of biopolymer mixtures and prediction of the properties for biomedical materials obtained

The experimental evaluation of structure formation in solutions of individual polymers, as well as in their mixtures with other polymers in order to predict the properties of materials obtained on their basis was the aim of this work. We used chitosan, sodium salt of chitosan succinyl, sodium salt of carboxymethyl cellulose, and polyvinyl alcohol. Distilled water, 1 % acetic acid, and buffer systems based on acetic acid and sodium acetate with pH = 3.80, 4.25, and 4.75 were used as solvents. It was found that the type of aggregates formed in polymer mixtures is determined by the nature of the solvent and the concentration of the polymers in the initial solution. A correlation has been shown between the nature of aggregates formed in solutions and some physicochemical properties of film materials obtained from solutions, namely, the degree of enzymatic hydrolysis, as well as the rate and degree of water vapor sorption by film materials. Thus, the studies carried out show that by varying the nature of the solvent, the concentration and nature of the polymers in the initial solutions, it is possible to control the structure formation in mixed polymer solutions, and, therefore, the properties of the resulting composites.