Olivera Šauperl

Characterization of amino groups for cotton fibers coated with chitosan

The adsorption of chitosan onto cellulose cotton fibers introduces antimicrobial properties, mainly created by the amount and location of amino groups. Therefore, it is important to be able to analyze both parameters, especially in a heterogeneous system, namely cotton fibers coated with chitosan. In this research, three different analytical techniques were applied to determine amino groups of cotton fibers coated with chitosan. The number of positively charged groups was determined indirectly by the spectrophotometric method using Acid Orange 7 dye, and the use of polyelectrolyte titration. In addition, the chemical surface composition regarding non-modified, as well as modified cotton fibers (coated with chitosan), was investigated using X-ray Photoelectron Spectroscopy (XPS). The results from a combination of these methods show that chitosan treatment introduces more than 14 mmol/kg of accessible amino groups onto the cotton fibers. The results were in good agreement with the results of XPS. The use of spectrophotometric and titration methods in combination with XPS appears to be a very useful tool for identifying the formation of amino groups in modified cotton fibers and their surfaces.

Cotton Cellulose 1, 2, 3, 4 Buthanetetracarboxylic Acid (BTCA) Crosslinking Monitored by some Physical—chemical Methods

In this research, the influence of the alkaline modification of cotton cellulose on the crosslinking with 1, 2, 3, 4 buthanetetracarboxylic acid (BTCA) is investigated. In order to anticipate changes after alkaline modification the crystallinity change was evaluated using wide angle X-ray diffraction (WAXD), iodine adsorption measurements, and the Knecht method. Tensiometry, the methylene blue method, and the streaming potential method enable hydrophilic/hydrophobic character estimation, carboxyl group content determination, evaluation of dissociation/sorption fiber characteristics, as well as electrokinetic properties characterization. All these parameters define the changes at the accessible polymer surfaces and therefore reflect the relationship between the changed crystallinity and the incorporation of the BTCA molecules into accessible regions of cotton cellulose. It has been concluded that the crystallinity degree characterizes crosslinking effectiveness of cotton cellulose crosslinked with BTCA. Mercerized materials show after crosslinking higher contact angles and retain a higher number of carboxyl groups. Electrokinetic properties are in correlation with carboxyl group amount. It has been confirmed that the physical—chemical methods which were used in this research are suitable methods for the crosslinking efficiency evaluation.

Antimicrobial and antioxidant functionalization of viscose fabric using chitosan–curcumin formulations:

The purpose of this work was to develop new additive combinations between chitosan and curcumin in solutions as a fiber-coating. Diverse additive combinations between chitosan and curcumin in solutions were adsorbed onto viscose fabrics in order to reach the essential antimicrobial and antioxidant functionalization for medical textiles. The goal of this paper was to examine the adsorption of these two compounds as an additive formulation on viscose textile material as well as to analyze the desorptions of both substances from the fabric surface. Finally, the antimicrobial and antioxidant properties of viscose fabrics functionalized by chitosan–curcumin formulations were respectively examined. Curcumin as an adsorbate for textiles in combination with chitosan represents an added-value because of its anti-oxidative properties, and showing the potential to enhance existing antimicrobial performance of chitosan when applied using the preferred procedure.

Differences Between Cotton and Viscose Fibers Crosslinked with BTCA

Presently polycarboxylic acids are being used for cellulose crosslinking. Among these, 1,2,3,4-buthanetetracarboxylic acid (BTCA) is the most effective in combination with a corresponding catalyst. In this research, a comparison of crosslinking effects on mercerized cotton fibers and viscose was identified using certain physical— chemical methods. The extent of crosslinking was evaluated using Fourier transform infrared (FT-IR) spectroscopy. The crosslinking of cellulose increases wrinkle resistance and reduces the mechanical properties, therefore, for this purpose the wrinkle recovery angle and the breaking force, was evaluated together with breaking elongation. When considering the crosslinking mechanism, those additional free BTCA carboxyl groups that are accessible in the cellulose polymer reflect the effectiveness of cotton-fiber crosslinking. The evaluation of accessible carboxyl was performed using the methylene blue method, where the adsorption of methylene blue dye on the cellulose material was monitored spectroscopically. The purpose of this research is mainly (i) to evaluate how different types of cellulose matrices/substrates influence the crosslinking of fibers crosslinked with different mass fractions of BTCA and (ii) to establish the most appropriate mass fraction of BTCA in the impregnation bath for sufficient crosslinking of mercerized cotton fibers, as well as viscose.

Viscose material functionalized by chitosan as a potential treatment in gynecology

This paper presents the functionalization of viscose cellulose material with chitosan for potential application in cellulose tampons for everyday use that would not display negative side effects, such as irritation of the vaginal wall, toxic shock syndrome, etc. The technological parameters of tampons, amount of amino groups due to chitosan adsorption, and the antimicrobial activity of the tampons were analyzed. Aqueous chitosan solutions buffered with lactic or acetic acid were sprayed on viscose fibers, from which tampons were prepared and dried at 40°C in an air chamber or at room temperature. Adsorption of chitosan was determined by conductometric titration. The absorptivity and antimicrobial activity of the tampons were determined by standard methods. It is concluded that tampons prepared in this way possess the following new properties: maintenance of the physiological pH of the vagina together with its moisturizing effect, good technical properties, and antimycotic, as well as antibacterial, activity.

A novel synergistic formulation between a cationic surfactant from lysine and hyaluronic acid as an antimicrobial coating for advanced cellulose materials

Abstract In this investigation, a novel coating for viscose fabric surface modification was developed using a synergistic formulation between a natural antimicrobial cationic surfactant from lysine (MKM) and a biopolymer hyaluronic acid (HA). The interaction between MKM and HA in aqueous solutions, as well as the interactions between their synergistic formulation (HA-MKM) and viscose fabric (CV) were studied using pH-potentiometric titrations’, turbidity measurements, the Kjeldahl method for the determination of nitrogen amounts, attenuated total reflectance fourier transform infrared spectroscopy, and scanning electron microscopy. The hydrophilic and antimicrobial properties of the functionalised CV were examined in order to evaluate its usages for medical applications. The results of the interaction studies showed that MKM and HA interact with each other by forming a precipitate when the binding sites of HA are saturated. The precipitate has a slightly positive charge at neutral pH due to excess binding of the MKM to HA. The excess positive charge was also detected on CV coated with HA-MKM. This was proven to be very beneficial for the antimicrobial properties of the functionalised CV. The antimicrobial tests showed exceptional antimicrobial activity of the functionalised CV against Escherichia Coli, StaphylococcusAureus, StreptococcusAgalactiae, Candida Albicans, and Candida Glabrata, making the CV fabric highly interesting for potential use in medicine.

Cellulose Fibres Funcionalised by Chitosan: Characterization and Application

Fibrous (textile) materials, such as used in the medical field or health services can be divided into two basic groups, according to whether they are used 1) inside organic tissues (internal/implantable): vascular grafts, meshes, stents, tendons and ligament implants, surgical threads, etc.) or 2) on their surface (external/non-implantable): gauzes, bandages, surgical covers, nappies, tampons, etc. The use of natural cellulose fibers, such as cotton and flax, goes back in medical applications to ancient times and still today, in some medical applications, cellulose fibrous materials represent materials that can not be exchanged with any other. In the more recent past new procedures and technologies enabled the production of various chemical cellulose fibers such as viscose, modal and lyocell, which are cleaner and even more hygroscopic than cotton, and as such highly applicable within hygiene and medical fields. The great potential of cellulose fibers lies in their molecular structure, which offers excellent possibilities as a matrix for the design of bioactive, biocompatible, and intelligent materials. Over the last twenty years the increase in the number of microbially caused diseases and hospital infections has led to intensive research into new materials and procedures, which would assure permanent bioactive effects together with complete safety for the people (Chung et al. 1998, Liu et al. 2000, Lee et al. 1999). Fungi, as well as gram positive and gram negative bacteria are commonly found in textile materials, especially in bedclothes. Many of these microorganisms are pathogens or potential pathogens and quite often related to nosocomial infections (Takai et al. 2002). Fibrous materials used in the medical and hygiene fields are usually in contact with extremely contaminated environments. Escherichia Coli and Penicillium Crysogenum very often cause diseases, as well as the disintegration and foul smell of fibrous materials (Chang et al. 1996). Therefore, the most important biomedical characteristics of a fibrous material for external use are its’ antimicrobial properties. In textiles these are usually achieved by treatments with silvers salts, quaternary ammonium chloride, metals, aromatic, halogen compouns, etc. (Kenawy et al. 2007, Takai et al. 2002). Antimicrobial agents act either as growth inhibitors (bacterioor fungi-static) or they kill the microorganisms (bio-cidal). Almost all antimicrobial agents used in convetional textile treatments are biocidal, as they damage the cell wall or the membrane permeability, denature proteins, inhibit enzyme activity or lipid synthesis, which are all essential for cell survival (Gao et. al. 2008). The most important issue regarding biocides used on commercial textiles is the potential induction of bacterial resistance to these substances, which could also

Antimicrobial efficiency evaluation by monitoring potassium efflux for cellulose fibres functionalised by chitosan

Abstract As there is a large gap in the field of fibre microbiological testing, the successful establishment of appropriate techniques is extremely appreciated. Antimicrobials prevent bacterial cell division by damaging the cell wall or affecting the permeabilities of cells’ membranes; they denature proteins, block enzyme activity, prevent cell survival, etc. Intracellular potassium cations are released by the inhibitions of pathogenic micro-organisms. Their quantitative determination enables monitoring of the bactericidal effect regarding antimicrobials. It can be used as an alternative technique for determining the inhibition of micro-organisms in contact with antimicrobial agents. Chitosan, a biodegradable natural polymer, possesses antimicrobial characteristics that depend on a number of factors such as the protonated amino groups’ quantities, degree of acetylation, molecular weight, solvents, etc. Over recent years chitosan has become extremely attractive for fibre functionalization usage. The aim of this paper was to apply spectrophotometry and potentiometry using potassium ion-selective electrode, respectively, for the quantitative analysis of potassium efflux, resulting from the degradation of micro-organisms’ membranes in contact with chitosan itself, as well as with cellulose fibres functionalised by chitosan.

Functionalization of polyethyleneterephthalate fibers using galactoglucomannan from spruce wood

Interest in researching biopolymers from renewable resources has risen over recent decades. Biopolymers that are byproducts within industrial production processes are of special importance, thus there is no need for additional fertile soil for their production. During the production of thermo-mechanical pulp within the paper industry, galactoglucomannans (GGMs) are dominant hemicelluloses and are released in large quantities in the processing of water as a byproduct. In this research a new possibility was investigated for the application of GGM from spruce wood. The influence of GGM adsorption from aqueous solutions onto polyethyleneterephthalate (PET) fibers on their surface properties and hydrophilic/hydrophobic character was thoroughly analyzed. The adsorption process was analyzed and optimized using quartz crystal microbalance with a dissipation unit. Total organic carbon determination was applied for evaluating the success of GGM adsorption onto PET fabric samples. The hydrophilic/hydrophobic character of treated fabrics was evaluated by moisture sorption determination as well as by water adsorption determination using tensiometry and water contact angles determination using goniometry. The results showed that even small amounts of adsorbed GGM significantly increased the hydrophilicity of PET fabric samples. Moisture content within standard atmosphere was increased by about 100%, water adsorption by about 250% and water contact angles were decreased from 125° to immediate spreading when comparing non-treated PET fabric with a GGM-treated one. The presented research proved the hypothesis that GGM from spruce wood is potentially highly applicable for functionalization of synthetic textile materials in order to significantly increase their surface hydrophilic characteristics.

Medical textiles based on viscose rayon fabrics coated with chitosan-encapsulated iodine: antibacterial and antioxidant properties

Adsorption of chitosan nanoparticles with embedded iodine was implemented onto pristine and oxidized cellulose viscose fabrics in order to introduce antimicrobial and antioxidative functionalization. The adsorption capacity, charging behavior and electrokinetic response of differently functionalized viscose at different pH values were analyzed by determining their zeta potential. Desorption studies, besides zeta potential measurements, were supported by polyelectrolyte titration. Finally, the antimicrobial properties were evaluated by the standard ASTM E2149 method, whilst antioxidative properties were determined by 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radical cation decolorization assay. It was found that the oxidation of viscose fabrics further modified by chitosan–iodine nanoparticles dispersion was a very promising functionalization process, providing good coating stability along with antimicrobial and antioxidant properties.