Biologically active fibers based on chitosan-coated lyocell fibers

Hydrogels Based on Proteins Cross-Linked with Carbonyl Derivatives of Polysaccharides, with Biomedical Applications

Adding carbonyl groups into the hydrogel matrix improves the stability and biocompatibility of the hydrogels, making them suitable for different biomedical applications. In this review article, we will discuss the use of hydrogels based on polysaccharides modified by oxidation, with particular attention paid to the introduction of carbonyl groups. These hydrogels have been developed for several applications in tissue engineering, drug delivery, and wound healing. The review article discusses the mechanism by which oxidized polysaccharides can introduce carbonyl groups, leading to the development of hydrogels through cross-linking with proteins. These hydrogels have tunable mechanical properties and improved biocompatibility. Hydrogels have dynamic properties that make them promising biomaterials for various biomedical applications. This paper comprehensively analyzes hydrogels based on cross-linked proteins with carbonyl groups derived from oxidized polysaccharides, including microparticles, nanoparticles, and films. The applications of these hydrogels in tissue engineering, drug delivery, and wound healing are also discussed.

A novel formulation of triethyl orthoformate mediated durable, smart and antibacterial chitosan cross-linked cellulose fabrics

Antibacterial, durable and smart cotton fabrics was developed using chitosan-based formulation. The cellulose was covalently cross-linked with chitosan using TEOF. The antibacterial activity of prepared smart fabrics and CS was studied against S. aureus and E. coli strains. The FTIR, SEM and XRD were employed to confirm the linkage of CS molecules with cellulose in cotton fabrics. The CS of 160 KDa extracted from shrimp shell showed the optimum antibacterial activity. The prominent asymmetric, symmetric alkyl CH peaks of CS were shifted to 2930 and 2845 (cm-1), respectively. Moreover, the shifted peaks at 1590 and 1400 (cm-1) indicate the CO stretching and NH2 bending bands of CS, respectively. This confirm the existence of new imine functional group that was generated after cross-linking of NH2 groups of CS. The SEM results showed more uniform morphology of TEOF cross-linked fabrics versus CS coated fabrics, which revealed a promising microbial growth inhibition activity. The TEOF as a cross-linker has been unveiled, showcasing the effectiveness of this innovative crosslinking approach. The fabric treated with cross-linked CS exhibited remarkable antibacterial properties that endured even after undergoing 30 washing cycles. These antibacterial textiles possess substantial commercial potential across a diverse range of industries.

Hydrothermal Synthesis of Chitosan and Tea Tree Oil on Plain and Satin Weave Cotton Fabrics

The paper aimed at enhancing the antimicrobial activity of chitosan by using tea tree essential oil with the purpose of durably finishing cotton fabrics for use in a hospital environment. The influence of crosslinkers and catalysts on the possibility of obtaining stable bonds using hydrothermal in situ synthesis between cellulosic material and chitosan with and without tea tree essential oil was investigated in detail. The morphology of the sample surface before and after the treatment and textile care cycle was investigated using a field emission scanning electron microscopy (FE-SEM) and indicated the presence of chitosan and a thin film on all treated samples, which showed durability of the treatment. The FTIR spectra obtained by Fourier transform infrared spectroscopy (FTIR) using attenuated total reflection measurement technique (ATR) analysis, showed that all the samples tested recorded physicochemical changes in the structure. The analysis of the samples on the goniometer proved the hydrophilicity of the materials, with a film forming on the surface of the treated samples, which is extremely beneficial given the end use of dressing samples to promote wound healing. The presence of a significant amount of bound chitosan with tea tree oil was confirmed by measuring the mass per unit area of the samples after the treatment and textile care cycles. The results of antimicrobial efficacy show that the materials treated with chitosan were resistant to bacteria and fungi in most cases, but only the samples treated in Bath I showed a zone of inhibition against the fungus Candida albicans, indicating the positive effect of tea tree essential oil.

Structure and properties of oxycellulose fabric crosslinked with soy protein

Cotton is an important renewable biopolymer with extensive applications in various fields including textiles. In the current study a soy protein (SP) crosslinked cotton fabric (SPCCF) was prepared through the reaction of carboxyl cotton fabric with soy protein without using crosslinking agents. FTIR analysis of SPCCF samples indicated that carboxyl groups in oxycellulose fabric have reacted with amino groups of SP to give the corresponding C-N bond, that was also reconfirmed by XPS spectra and TGA/DTG analyses of the grafted fabrics. The resulting SPCCF fabrics acquired under the optimized conditions exhibited the improved tensile strength and capillary effect as compared to the oxidized cotton fabric. The ungrafted and grafted fabrics were further evaluated for dyeing property, as a result, the SPCCF fabrics showed markedly improved colour strength when dyed with acid dyes. The fastness properties of dyeability for the dyed SPCCF fabrics were also good compared with that of ungrafted fabrics by dyeing. Shikonin as a kind of Chinese medicine was found to immobilize on the SPCCF fabric through treatment with shikonin aqueous solution, such fabric displayed effective antibacterial activities against both gram-positive and gram-negative bacteria with durability of 30 washes. These results suggest that the SPCCF can be suitable for medical protective textiles by immobilizing drugs.

Antibacterial modification of Lyocell fiber: A review

As the most successful regenerated cellulose fiber developed in recent decades, Lyocell has attracted much attention due to its useful properties, simple manufacturing process, and recyclable solvent. However, Lyocell's lack of antibacterial properties limits its application in medical and health fields. Antibacterial modification of Lyocell fiber can be achieved by three general approaches: physical blending, chemical reaction, and post-treatment. Physical blending methods introduce antibacterial agents directly into the spinning dope. In chemical reaction methods, functional groups of the antibacterial additives are grafted or crosslinked into Lyocell fibers, thereby imparting antimicrobial properties. In post-treatment methods, antibacterial additives are deposited on Lyocell fiber surfaces by physical coating, padding, or impregnation processes. We organize our review of antibacterial modification of Lyocell fibers by these preparation methods. Some of the modified Lyocell fibers are reported to exhibit improved antimicrobial activity against various bacteria and fungi, indicating promise for application in medical or hygienic products.

A review on applications of chitosan-based Schiff bases

Biopolymers have become very attractive as they are degradable, biocompatible, non-toxic and renewable. Due to the intrinsic reactive amino groups, chitosan is vibrant in the midst of other biopolymers. Using the versatility of these amino groups, various structural modifications have been accomplished on chitosan through certain chemical reactions. Chemical modification of chitosan via imine functionalization (RR'CNR″; R: alkyl/aryl, R': H/alkyl/aryl and R″: chitosan ring) is significant as it recommends the resultant chitosan-based Schiff bases (CSBs) for the important applications in the fields like biology, catalysis, sensors, water treatment, etc. CSBs are usually synthesized by the Schiff condensation reaction between chitosan's amino groups and carbonyl compounds with the removal of water molecules. In this review, we first introduce the available synthetic approaches for the preparation of CSBs. Then, we discuss the biological applications of CSBs including antimicrobial activity, anticancer activity, drug carrier ability, antioxidant activity and tissue engineering capacity. Successively, the applications of CSBs in other fields such as catalysis, adsorption and sensors are demonstrated.

Recent advances in chitosan polysaccharide and its derivatives in antimicrobial modification of textile materials

Chitosan is partially or completely N-deacetylated derivative of chitin and is chemically composed of β‑(1, 4) linked 2‑amino‑2‑deoxy‑β‑d‑glucopyranose. Biocompatibility, non-toxicity, antifungal activity, water-binding capacity, bioactivity and antimicrobial properties make chitosan particularly attractive substitute for synthetic polymers in different application fields and notably in the textile industry. The presence of reactive amino and hydroxyl groups along the backbone conifer chitosan some interesting properties for use in textile dyeing and finishing. However, the main barrier to the use of chitosan is the lack of water solubility at neutral pH and poor durability on textile surfaces. To overcome this, chitosan has been chemically modified in several ways to obtain a wide range of important derivatives with a broad range of applications. This review is intended to provide a recent overview of chitosan and its derivatives and highlight their role in the development of antimicrobial textiles.

Application of Chitin/Chitosan and Their Derivatives in the Papermaking Industry

Chitin/chitosan and their derivatives have become of great interest as functional materials in many fields within the papermaking industry. They have been employed in papermaking wet-end, paper surface coating, papermaking wastewater treatment, and other sections of the papermaking industry due to their structure and chemical properties. The purpose of this paper is to briefly discuss the application of chitin/chitosan and their derivatives in the papermaking industry. The development of their application in the papermaking area will be reviewed and summarized.

Loading of chitosan - Nano metal oxide hybrids onto cotton/polyester fabrics to impart permanent and effective multifunctions

New and durable multifunctional properties of cotton/polyester blended fabrics were developed through loading of chitosan (Cs) and various metal oxide nanoparticles (MONPs) namely ZnO, TiO₂, and SiO₂ onto fabric surface using citric acid/Sodium hypophosphite for ester-crosslinking and creating new anchoring and binding sites, COOH groups, onto the ester-crosslinked fabrics surface. The surface morphology and the presence of active ingredients (Cs & MONPs) onto selected - coated fabric samples were analyzed by SEM images and confirmed by EDS spectrums. The influence of various finishing formulations on some performance and functional properties such as wettability, antibacterial activity, UV-protection, self-cleaning, resiliency and durability to wash were studied. The obtained results revealed that the extent of improvement in the imparted functional properties is governed by type of loaded-hybrid and follows the decreasing order: Cs-TiO₂NPs>Cs-ZnONPs>SiO₂NP_s>Cs alone, as well as kind of substrate cotton/polyester (65/35)>cotton/polyester (50/50). Moreover, after 15 washing cycles, the durability of the imparted functional properties of Cs/TiO₂NP_s - loaded substrates marginally decreased indicating the strong fixation of the hybrid components onto the ester-crosslinked substrates. The obtained bioactive multifunctional textiles can be used for producing eco-friendly protective textile materials for numerous applications.

Structure and properties of cotton fabrics treated with functionalized dialdehyde chitosan

In this research, modified cotton fabrics were prepared by pad-dry-cure technique from the aldehyde chitosan solution containing 3-aminopropyltriethoxysilane (APTES) and 1,2-ethanediamine (EDA) respectively. The structural characterization of the modified cotton fabrics was performed by attenuated total reflection ATR, scanning electron microscopy (SEM) and thermogravimetry (TG) analysis and physical mechanical properties were measured. The adsorption kinetics of modified cotton fabrics were also investigated by using the pseudo first-order and pseudo second-order kinetic model. The dyeing rate constant k1, k2 and half adsorption time t1/2 were calculated, respectively. The results show that the mechanical properties of different modified cotton fabrics were improved, and the surface color depth values (K/S), UV index UPF and anti-wrinkle properties were better than those of untreated cotton. Dyeing kinetics data at different temperatures indicate that Direct Pink 12B up-take on the modified cotton fabrics fitted to pseudo second-order kinetic model.

Blending of Cellulose and Chitosan in Alkyl Imidazolium Ionic Liquids

The production of cellulose/chitosan blends in alkyl imidazolium ionic liquids (ILs) was studied in this work. Selected organic solvents, such as dimethyl sulfoxide, ethyl acetate, and diethyl ether, were used as cosolvents. The addition of cosolvents decreased the viscosity of cellulose/chitosan solutions in ILs and facilitated the dissolution of polysaccharides, thereby decreasing the and polymer aggregates sizes in the solutions. The cellulose/chitosan films were produced from the studied solutions. The presence of one of cosolvent and ILs in the blended films was confirmed by FTIR spectroscopy. The blended film is stronger than pure cellulose film, and the addition of cosolvents has an influence on its mechanical properties.