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Metal and metal oxides in nano-sized particles have recently shown great potentials to obtain multifunctional textiles. However, multifunctional textiles with durable characteristics are still challenging to achieve by using eco-friendly fixing agents. In this work, cotton, linen, viscose, polyester fabrics, and their blends with different weaving structures were treated by TiO2-NP emulsions containing an eco-friendly binding agent. Itaconic acid, a water-soluble monomer, was used as a green alternative to acrylic-based binding agent in order to provide durable finishing. The treatment parameters have been optimized on 100 % cotton fabrics. Hexamethyltriaminophosphine (HMTAP), organic compound contains phosphorus and nitrogen atoms, was employed as fire-retardant agent in the treatment emulsions by which at 2.5 %v/v superior performance on the vertical fire test was achieved. Nanoparticles deposition was confirmed by SEM-EDX test. Treated samples showed very high UPF values with all type of fabrics to reach 277, 144, 287 and 201 for cotton sample, cotton/PET, PET and PET/viscous, respectively. However, linen fabric with very loose weaving structure showed the lowest UPF values. Antimicrobial activities of the treated samples at as less as 1.5 % wt/v TiO2 showed over 90 % reduction of Gram-positive and Gram-negative bacteria, conducted under halogen light bulb, compared to the untreated.

Hydrogel is considered as a promising candidate for bioink in terms of biocompatibility, biodegradability, printability and supporting cellular behavior. Recently, carbohydrates derivatives containing alkyne and azide pendant functional groups have been used in medical applications due to their improved chemical, biological, functional properties, and their amenability for chemical reactions under mild conditions. In this work, a novel bioink was developed based on azide and alkyne of cellulose derivatives. Azido-hydroxyethyl cellulose (D.Sazido = 0.04) was synthesized via open-ring reaction of 1-azido-2,3-epoxypropane and characterized spectroscopically and titrimetrically. Alkyne derivative, propargyl carboxymethyl cellulose (D.Spropargyl = 1.72) was synthesized through coupling reaction with propargylamine in the presence of EDC and NHS. The click-gel scaffold was obtained by mixing the two novel candidates in the presence of copper (I) catalyst. Extrusion bio-plotting experiment was successfully conducted of the two solutions into coagulant Cu (I)/DMSO solutions and demonstrated the possibility of using the clickable cellulose derivatives as bioink precursors. Chemical and physical properties of the click-gel were demonstrated. The biocompatibility assay of the prepared click-gels showed high level of viability in the human skin fibroblast cells (HFB4) at concentration 100 μg/mL.

From the environmental point of view, there is high demand for the preparation of polymeric materials for various applications from renewable and/or waste sources. New lignin-based spun fibers were produced, characterized, and probed for use in methylene blue (MB) dye removal in this study. The lignin was extracted from palm fronds (PF) and banana bunch (BB) feedstock using catalytic organosolv treatment. Different polymer concentrations of either a plasticized blend of renewable polymers such as polylactic acid/polyhydroxybutyrate blend (PLA-PHB-ATBC) or polyethylene terephthalate (PET) as a potential waste material were used as matrices to generate lignin-based fibers by the electrospinning technique. The samples with the best fiber morphologies were further modified after iodine handling to ameliorate and expedite the thermostabilization process. To investigate the adsorption of MB dye from aqueous solution, two approaches of fiber modification were utilized. First, electrospun fibers were carbonized at 500 °C with aim of generating lignin-based carbon fibers with a smooth appearance. The second method used an in situ oxidative chemical polymerization of m-toluidine monomer to modify electrospun fibers, which were then nominated by hybrid composites. SEM, TGA, FT-IR, BET, elemental analysis, and tensile measurements were employed to evaluate the composition, morphology, and characteristics of manufactured fibers. The hybrid composite formed from an OBBL/PET fiber mat has been shown to be a promising adsorbent material with a capacity of 9 mg/g for MB dye removal.

Lignocellulosic materials such as agricultural residues have been identified as potential sustainable sources that can replace petroleum-based polymers. This study focused on the conversion of lignin extracted from bagasse to carbon fiber (CF) and cellulose nanocrystal (CNC). The highest extraction of lignin yield was achieved at 100 °C using 10% NaOH for 12 h. Carbon fibers were obtained by electro-spinning of bagasse lignin blended with polyvinyl alcohol (PVA) (11 wt/v %) followed by thermo-stabilization (250 °C) in an oxidizing atmosphere and further carbonization in an inert atmosphere (850 °C). Conventional hydrolysis process was used to extract cellulose nanocrystal from bagasse pulp. Morphological (scanning electron microscopy, SEM), spectral (Fourier transform infrared, FTIR) spectroscopy, elemental analysis, thermal characterization and surface area measurements have been carried out. Figures originated by SEM showed that CF ranges from 145 to 204 nm, while stabilized bagasse cellulose nanocrystal (SCNC) appeared as rod-shape like structure in the range of length 600–800 nm and diameter 5.33–19 μm. Characterization results revealed that CF exhibits microporous structure, while bagasse lignin and SCNC display mesoporous structure. In addition, the results proved that SCNC exhibits a percentage removal 71.56% for methylene blue dye in an aqueous solution.

Encapsulation of volatile essential oils has been investigated to provide an active food packaging (AFP) material with more control over their fast release and pungent smell. In this work, Gum Arabic-based adhesive membrane was developed as a self-stick AFP material, delivering cinnamon essential oil (CEO) in vapor phase. Gum Arabic (GA) was grafted with butyl acrylate (BA) and hydroxyethyl methacrylate [GA-g-poly(BA-HEMA)]. Adhesive membrane was characterized by means of spectral, physicochemical and rheological analysis. GA-adhesive membrane made of 5% wt/v GA, 3.5 m mol HEMA, and 87 m mol BA with 21 N/m tack are loaded with 4, 8 and 10% v/v of CEO and used for antimicrobial bioassays. GA-g-poly(BA-HEMA) membrane prolonged CEO release up to 2 days. 8%v/v CEO showed superior activities against both Gram negative and positive bacteria. Shelf-life of cheese samples, packed with the self-stick membranes loaded with cinnamon extract, has extended from 3 to 8 weeks. Cheese samples that inoculated with shiga toxin producing E. coli O157:H7 and packed in plastic boxes with the self-stick AFP (4, 8 and 10 % CEO), showed significant reduction in the total bacteria counts.

Carbohydrates derivatives containing propargyl pending functional groups have been used in medical applications due to their improved chemical, biological, and functional properties. In this work, azide and alkyne pendant functional groups were introduced onto ethyl cellulose (EC) and β-cyclodextrin respectively in order to demonstrate the ability of scaffold formation by click chemistry. Technically, Azido-ethyl cellulose (D.S.Azido 0.19) and 2, 3, 6-O- propargylated β –cyclodextrin were synthesized and characterized as click-triggered candidates. The click-gel scaffold was obtained by mixing the two novel candidates in the presence of copper catalyst. Azido-EC was considered to produce clickable electrospun fibers blended with EC (290–620 nm) at 20 kV in order to functionalized EC substrate bearing azide groups to be amenable towards immobilization of an alkyne-terminated bio-molecules. The biocompatibility assay of the prepared click-triggered candidates showed very high level of viability in the human skin fibroblast cells (HFB4) at concentration 100 μg/ml.

Conjugated linoleic acids (CLA) as essential fatty acids (EFAs) have shown medical significance towards wound healing process. However, EFAs whose chemical structures possess unsaturated double bonds are unstable to environmental degradation. Encapsulation of EFAs into protective layer was the basic approach to avoid such degradation. In this work, CLA was extracted from sunflower oil, purified and characterized by spectral analysis. CLA was loaded into two different substrates namely hydrophobic, cellulose acetate (CA), and hydrophilic, liposomal emulsions of poly (vinylalcohol) (PVA) and gelatin, polymers. Electrospinning parameters were optimized to obtain clear, smooth and bead-free fibers. 12 % wt/v of CA shows bead-free fibers with diameter in range of 440-300 nm loaded with CLA up to 26% wt/wt. While, CLA (3% wt/wt) is encapsulated into the liposomal emulsions of PVA and gelatin with average fiber diameters 252-400 nm and 120-200 nm respectively. The CLA encapsulation, morphology of the electrospun fibers, and fiber diameter were examined using scanning electron microscopy (SEM). Viscosity and conductivity of the prepared solutions for electrospinning were demonstrated. Biocompatibility was evaluated by measuring cell proliferation of skin fibroblast cells. The release profile was investigated by UV- Visible spectroscopy. CLA loaded into the electrospun showed lower peroxide values (PV) of CLA.

This study suggested that methylseleninic acid (MSA) could respond to the inflammatory signaling associated with ionizing radiation-induced testicular damage. Mature male rats were divided into four groups: negative control, whole body γ-irradiated (IRR) (5 Gy), MSA (0.5 mg/kg, daily for nine consecutive days), and MSA+ IRR groups. MSA increased serum testosterone level and testicular glutathione peroxidase (GPx) as well as decreased the percentage of sperm abnormalities. Radiation prompted inflammatory signaling in the testes through increasing phospho-janus kinase1 (p-JAK1), phospho-signal transducers and activators of transcription 3 (p-STAT3) protein expressions. This induced increment in the inflammatory markers including nuclear factor- kappa B (NF-κB) and interleukin-1beta (IL-1β) levels. Also, radiation induced elevation of nitric oxide (NO) and malondialdhyde (MDA) levels with consequent reduction in testicular reduced glutathione level (GSH) and superoxide dismutase (SOD) activity. MSA significantly counteracted the radiation effect on testicular nuclear factor erythroid-2-related factor-2 (Nrf2) and suppressor of cytokine signaling (Socs3) protein expressions. In summary, this investigation proposed that MSA preserved spermatogenesis through increasing testosterone levels and GPx activity. Additionally, it diminished testicular inflammation by increasing of Nrf2 and Socs3 levels leading to reducing of p-JAK1, p-STAT3 and NF-κB levels. Histopathological examination results of testicular tissues showed a coincidence with the biochemical analysis.

Chloramphenicol, antibiotic drug is widely used in the developing countries, may cause bone marrow suppression during its topical treatment and affecting red blood cells. Because the accumulation of high dose of chloramphenicol is necessary for this side effect, controlling its release rate is a possible approach to reduce the risk of its topical application. In the present work, chloramphenicol was encapsulated into gelatin electrospun fibers that cross-linked with non-toxic crosslinker. β-cyclodextrin, cyclic oligosaccharides of 7 membered-sugar ring, was selectively oxidized to cleave the carboncarbon bond in positions C-2 and C-3 of the glucose units to yield two aldehyde groups and end up with poly aldehyde β- cyclodextrin (PA-β-CD). Matrix was designed to control chloramphenicol release rate from nontoxic and biodegradable electrospun mat for topical applications. Bead-free electrospun fibers were produced at the concentration of 24 % w/v gelatin solution at 15 kV with gap distance of 17 cm with a flow rate of 2 ml/hr. Electrospun fibers were produced in the nanoscale (450-150 nm). 6 % of chloramphenicol was chosen to carry out the cross-linked matrices by using PA-β-CD. The encapsulation efficacy was investigated by UV-isible spectroscopy and the antimicrobial activities were demonstrated against Staphylococcus aureus (gram positive) and Pseudomonas aeruginosa (gram negative bacteria) and Candida albicans. The results showed that the samples have a strong inhibitory activity against all pathogenic microorganisms used.

Uncontrolled hemorrhage continues to be the leading cause of death from traumatic injuries both in the battlefield and in the civilian life. Chitosan is among the very few materials that have made the short list of military recommended field-deployable hemostatic dressings. However, the detailed mechanism of its action is still not fully understood. Moreover, in the cases when patients developed coagulopathy, the efficacy of the dressings rely solely on those mechanisms that work outside of the regular blood coagulation cascade. In addition to the well-known erythrocyte agglutination, we proposed to use the reactive N-iodoacetyl group on a new chitosan derivative to accelerate hemostasis. In this paper, we describe the synthesis of chitosan iodoacetamide (CI) with considerations of the stoichiometry among the reagents, the choice of solvent, the pH of the reaction medium, and the reaction time. The reaction was confirmed by FT-IR, 1H and 13C NMR, elemental analysis, iodine content analysis, and SEM-EDS. Water contact angle measurements and Erythrocyte Sedimentation Rate (ESR) method were used to evaluate the hemostatic potential of the newly synthesized CI as a function of their degree of substitution (DS). The range of DS was 5.9% to 27.8% for CI. The mid-range of DS gave the best results for the ESR. CIs exhibit favorable cytocompatibilities up to DS 18.7 compared to the generic unmodified chitosan. In general, the biocompatibility of chitosan iodoacetamide slightly declined with increasing the iodide content up to DS 21.5 owing to its affinity to SH groups of cells.

Chemical crosslinking hydrogels provide irreversible matrices with reliable characteristics for wider medical applications. When hydrogels used for hosting bioactive substances, matrices have to be crosslinked at mild condition with high yield reaction and inactive to the biological molecules. In this work, chitosan was functionalized with active double bonds as a precursor to hydrogel that gels at body temperature. Free-radical crosslinking was conducted in the presence of maleic anhydride (MA) and potassium persulfate (KPS). The chemical structures of hydrogels were confirmed via spectral analysis. Mechanical and gelation characteristics of the hydrogels were tuned by using different molar ratios of MA and KPS. Pores size was controlled according to the crosslinking density in range of 313–866 μm that agrees proportionally with the swelling degree. Young's modulus values were tuned to span from 6 to 31 Pa with opposite relationship with the stress at break that varied from 6 to 17 Pa. Hydrogel release profiles were plotted representing varied releasing rates. Gels were obtained at 37 °C for 2 h using KPS (24–48 mM) and different concentration of MA (0.17, 0.35 and 0.5 M). The tetrazolium dye 3-(4,5-dimethylthiazol-2-yl)-2,5diphenyltetrazolium bromide (MTT), colorimetric, biological assay using skin fibroblast cells showed high biocompatibility of chitosan-based hydrogels.

Functionalization of starch with oxidative cleavage reaction to yield the corresponding dialdehyde derivatives has been employed as an approach for gel formation via Schiff's base reaction. However, this reaction is known as reversible and hydrolysable in aqueous solutions. In this study, the potential of hydrazone chemistry to be used in the synthesis of stimuli‐free and stable hydrogels is investigated. Soluble starch is selectively oxidized to give aldehydic‐starch with different aldehyde contents 39.9, 34.6, and 22.6 aldehyde group/100 anhydroglucose unit (AGU). Adipic dihydrazide was used as an α‐effect nucleophile to react with the dialdehyde starch and obtain stable hydrazone‐based and stimuli‐free hydrogels. Hydrazone chemistry of aldehydic‐starch and adipic dihydrazide (AD) is demonstrated by spectral analysis. As well, the biocompatibility with human skin fibroblasts cells is investigated using a cytotoxicity assay. SEM images show the pore sizes vary from 575 to 4752 nm related to AD concentrations. The swelling degree recorded an increase of 900%, 500%, and 600% at pH 4, pH 7, and pH 9, respectively. Hydrogels showed varied mechanical behavior as a function of AD concentrations.

Utilization of polysaccharides as precursors to develop new polymer gels has been growing recently due to their superior inherent properties such as biodegradability, chemical activity, biocompatibility, non-toxicity, abundance, and affordable price. This chapter discusses polymer gels in terms of chemical structures, modifications, the main properties of promising polysaccharide precursors, the most common crosslinkers, and methods of crosslinking either by physical or chemical methods along with mode of interactions. It also highlights the different techniques used to characterize and evaluate the performance and functional properties of the fabricated gels as well as their potential applications in different fields. Finally, recent developments and future trends are considered to cope with the growing demands for engineering novel polymer gels for further ecofriendly successful applications.

a b s t r a c t A method to impregnate silver nanoparticles (AgNPs) into different polysaccharides substrates (cellulose powder (CP), microcrystalline cellulose (MCC), carboxymethyl cellulose (CMC) and chitosan (Chit)) by using glucose as reducing agent, is presented. X-ray diffraction analyses of polysaccharides coated with AgNPs showed the formation of silver particle sizes in the range of 3.7–5.6 nm and have almost spherical shape. The entire prepared composite shows antimicrobial effect. The antibacterial activity of polysaccharides loaded with silver nanoparticles was evaluated against Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus) bacteria. The results suggest excellent antibacterial activity.

Ricinoleic acid (RA) is a C18 fatty acid (FA) with a double bond at the C 9 position and a hydroxyl group at the C(12) position (cis-12-hydroxyoctadeca-9-enoic acid). Recently, RA has been reported as a pro/anti-inflammatory and analgesic agent for topical applications to be considered as an alternative to irritant substances that relive pain. However, RA when it is exposed to air, it reacts with the oxygen and decomposes into short-chain aldehydes and ketones. Moreover, pathologically, small amount of anaesthetic agent acts on peripheral nerves, producing reversible block in transmission of peripheral nerves impulses. However, larger amounts effect potentially in the central nervous system and may cause cardiac arrest. Accordingly, extended release formulations for local anaesthetic agent such as encapsulation, are highly demanded if the drug will be used for long period. In this work, ricinoleic acid, extracted and characterized, was encapsulated into a new matrix made of phospholipid liposomes and chitosan to protect and control RA release. RA release was controlled by crosslinking the matrices using glutaraldehyde. Spectral and morphology analysis are used to characterize the produced microshpers. The cytotoxicity test is considered to examine the final product biocompatibility. The encapsulation efficiency was investigated by UV- Visible spectroscopy.

In recent years, cyclodextrin applications have been expanding to include textile finishing, providing new and unique functionalities to the fabric substrates. In this work the grafting of Per-(2,3,6-O-allyl)-β cyclodextrin by plasma and conventional thermofixation methods is described. The fabric substrate was cotton and activated by the surface modification of the fibers by the synthesis of iododeoxycellulose, cellulose peroxide, and a cellulose diazonium salt. Several plasma machines and conventional thermal techniques for fixation were studied. Iododeoxycellulose gave the best results by thermofixation and the in situ mode of the APJeT atmospheric plasma machine. Linoleic, ricinoleic, oleic acids were included in the grafted cyclodextrin fabrics as possible wound healing agents. The cyto-compatibility of the treated samples either included or un-included with fatty acids shows promising results.

Starch derivatives with anionic functional groups have attracted a lot of attention because of their potentials in the industrial applications. Commonly anionic starch derivatives possess gelatinization temperatures lower than that of native starch that is broadening its applications in industrial processes operated at low temperature. In this work, new starch derivatives containing sulfonated functional groups were prepared through intermediate triazinyl compounds. Four different bridging compounds were synthesized and characterized via spectral analysis. The sulfonated triazinyl compounds were reacted with native starch to obtain different density of sulfonic acid groups on starch backbone. Native starch was reacted with mono/dichlorotriazine-4-aminobenzene-sulfonic acid and mono/dichlorotriazine-4-aminobenzene 1,3-disulfonic acid. The sulfonic acid groups were introduced in different degree of substitutions (0.043, 0.032, 0.006 and 0.008) which caused charge repulsion along the starch chains and resulted in keeping chains stretched and therefore less affected with pH and temperature. Ultimately, the produced anionic starch derivatives possess gelatinization temperatures lower than that of native starch that is broadening its applications in industrial processes operated at low temperature.

Several polymers of both natural and synthetic origin have been used for a variety of biomedical applications including pharmaceutical preparations, drug targeting, imaging, drug delivery, prosthetics, and tissue engineering scaffolds. Due to their reproducible characteristics in terms of their molecular weight, degradation and mechanical properties, synthetic polymers are attractive for a variety of the aforementioned applications. However, synthetic polymers from the biological standpoint, synthetic polymers often lack much-desired bioactivity and biocompatibility, which may translate into adverse side effects. Natural polymers on the other hand are abundant and resemble the components present in biological extracellular matrices. Thus, natural polymers are readily accepted by the body and possess high bioactivity and biocompatibility. Natural polymers can be divided into three major classes according to their chemical structure: (i) polysaccharides, (ii) proteins, and (iii) polyesters. This chapter presents an overview of the polysaccharide-based biomaterials, their structure property, and applications in the area of drug delivery and tissue engineering. Particular emphasis is given to polysaccharides such as (i) hyaluronic acid (HA), (ii) chondroitin sulfate, (iii) chitin and chitosan, (iv) alginates, and (v) cellulose. These polymers and their popular derivatives are also discussed in the context of their chemical and biological properties. Polysaccharides in their native form may not be able to provide all the desired properties for a particular biomedical application. Thus, the chapter also focuses on the polysaccharide derivatives and their blend with other polymers for a variety of biomedical applications.

Radiotherapy is a major factor contributing to female infertility by inducing premature ovarian failure (POF). Therefore, the need for an effective radioprotective agent is evident. The present study investigated the mechanism of potential radioprotective effect of sodium selenite on radiation-induced ovarian failure and whether sodium selenite can stimulate in-vivo follicular development in experimental rats. Immature female Sprague-Dawely rats were either exposed to gamma-radiation (3.2 Gy, LD(20)), once and/or treated with sodium selenite (0.5 mg/kg), once daily for one week before irradiation. Follicular and oocyte development, apoptotic markers, proliferation marker as well as oxidative stress markers were assessed 24-h after irradiation. In addition, fertility assessment was performed after female rats became completely mature at two months of age. Sodium selenite significantly enhanced follicular development as compared to the irradiated group. Sodium selenite significantly reversed the oxidative stress effects of radiation that was evidenced by increasing in lipid peroxide level and decreasing in glutathione level, and glutathione peroxidase (GPx) activity. Assessment of apoptosis and cell proliferation markers revealed that caspase 3 and cytochrome c expressions markedly-increased, whereas, PCNA expression markedly-decreased in the irradiated group; in contrast, sodium selenite treatment prevented these alterations. Histopathological examination further confirmed the radioprotective efficacy of sodium selenite and its in-vivo effect on ovarian follicles' maturation. In conclusion, sodium selenite showed a radioprotective effect and improved folliculogenesis through increasing ovarian granulosa cells proliferation, estradiol and FSH secretion, and GPx activity, whilst decreasing lipid peroxidation and oxidative stress, leading to inhibition of the apoptosis pathway through decreasing the expressions of caspase 3 and cytochrome c.

The potential value of selective and non-selective COX-2 inhibitors in preventing some of the biochemical changes induced by ionizing radiation was studied in rats exposed to carrageenan-induced paw edema and 6-day-old air pouch models. The animals were exposed to different exposure levels of gamma-radiation, namely either to single doses of 2 and 7.5 Gy or a fractionated dose level of 7.5 Gy delivered as 0.5 Gy twice weekly for 7.5 weeks. The inflammatory response produced by carrageenan in irradiated rats was markedly higher than that induced in non-irradiated animals, and depended on the extent of irradiation. Celecoxib, a selective COX-2 inhibitor, in doses of 3, 5, 10, and 15 mg/kg was effective in reducing paw edema in irradiated and non-irradiated rats in a dose-dependent manner as well as diclofenac (3 mg/kg), a non-selective COX inhibitor. Irradiation of animals before the induction of the air pouch by an acute dose of 2 Gy led to a significant increase in leukocytic count, as well as in the level of interleukin-6 (IL-6), interleukin-1beta (IL-1beta), tumor necrosis factor-alpha (TNF-alpha), LTB(4), PGE(2) (as an index of COX-2 activity), TXB(2) (as an index of COX-1 activity), and the plasma level of MDA. This increase in level of these parameters was more marked than that observed in the non-irradiated animals subjected to the inflammagen. The blood GSH level was not affected by the dose of irradiation used, whereas superoxide dismutase (SOD) activity was suppressed. In many respects, celecoxib (5 mg/kg) was as potent as diclofenac in decreasing the elevated levels of IL-6, IL-1beta, TNF-alpha, LTB(4), PGE(2), but lacked any significant effect on TXB(2) level. Since it is mostly selective for COX-2 with a rare effect on COX-1 enzyme, both drugs at the selected dose levels showed no effect on level of MDA, GSH, and SOD activity.