Chitosan-Based Sustainable Textile Technology: Process, Mechanism, Innovation, and Safety

This chapter reviews relevant findings regarding the activities and contributions of chitosan in different textile processing following the varieties of process, mechanism, and applications. Chitosan is a better candidate in both aspects of biodegradability and efficiency instead of synthetic polymers. The technical and scientific discussions behind the role of chitosan in all the processes and treatments have been explored in the chapter. Over the last few years, enormous efforts and challenges are being practiced in research and industry to design and development of eco-friendly and sustainable technologies. Therefore, the chapter emphasizes on chitosan-based formulations of fibers, fabrics, coatings, and functional textiles

Chitosan–Carboxymethylcellulose-Based Polyelectrolyte Complexation and Microcapsule Shell Formulation

Chitosan (CH)–carboxymethyl cellulose sodium salt (NaCMC) microcapsules containing paraffin oil were synthesized by complex formation, and crosslinked with glutaraldehyde (GTA). The electrostatic deposition of NaCMC onto the CH-coated paraffin oil emulsion droplets was demonstrated by zeta potential and optical microscopy. The optimal process conditions were identified in terms of pH of the aqueous solution (5.5) and CH/NaCMC mass ratio (1:1). Encapsulation of paraffin oil and microcapsule morphology were analyzed by ATR-FTIR and SEM, respectively. The effect of GTA crosslinking on paraffin oil latent heat was investigated by DSC and combined with the values of encapsulation efficiency and core content, supporting the compact shell formation

Solubility of Chitin: Solvents, Solution Behaviors and Their Related Mechanisms

Chitin is a natural polysaccharides having a unique molecular arrangement of 2-(acetylamino)-2-deoxy-d-glucose, it possesses multifunctional properties and is suitable for various applications mainly in pharmaceutical, biomedical food, textiles and packaging fields. Therefore, being considered as a superior material for a sustainable future of industrial development, chitin perfectly meets up the demands with diversified functionalities in applications, excellent biocompatibility and biodegradability. Non-toxicity to human and environment (air, water and soil) is a great opportunity for this revolutionary, innovative and sustainable material. Moreover, antibacterial potency and low immunogenicity of chitin have broadened the aspects of research and development on structure-function relationship toward biological tissues and activities. Despite abundance, low cost and availability, many experimental data from potential studies, reproducibility problems of chitin solubility measurement still limit the development of products and access to the market in large volume. Batch-to-batch variability, non-precise characterization and randomly distributed acetyl groups of chitin structure eventually results in a bad reproducibility of chitin solubility. Therefore, the chapter aims to organize the information of chitin structure at molecular level and correlate solubility with chitin structure. Moreover, the dissolution mechanism and solution behaviors in different solvents will be discussed in this chapter

Far-Infrared Emission Properties and Thermogravimetric Analysis of Ceramic-Embedded Polyurethane Films

The far-infrared ray (FIR) is one kind of electromagnetic wave employed for numerous bio-interactive applications such as body thermoregulation, infrared therapy, etc. Tuning the FIR-emitting property of the functional textile surface can initiate a new horizon to utilize this property in sportswear or even smart textiles. Ceramic particles were studied for their unique ability to constantly emit FIR rays. The purpose of this research is to characterize the FIR emis-sion properties and the thermogravimetric analysis of ceramic-embedded polyurethane films. For this purpose, ceramic particles such as aluminum oxide, silicon dioxide, and titanium diox-ide were incorporated (individually) with water-based polyurethane (WPU) binder by a soni-cation technique to make a thin layer of film. Significant improvement in FIR emissive property of the films was found when using different ceramic particles into the polyurethane films. Re-flection and transmission at the FIR range were measured with a gold integrating sphere by Fourier-transform infrared (FTIR) spectrometer. The samples were also characterized by ther-mogravimetric analysis (TGA). Different physical tests, such as tensile strength and contact angle measurements, were performed to illustrate the mechanical properties of the films. The study suggested that the mechanical properties of the polyurethane films were significantly influenced by the addition of ceramic particles

Assessment of antioxidant and drug releasing properties of cellulose fabrics functionalized with polymeric nanoparticles as potential biofunctional garments

Drug administration through skin raised a great interest as a not invasive and sustained method to deliver active substances both at topical and systemic levels. Biofunctional textiles are a new class of materials that combine conventional fabrics with advanced drug delivery systems in order to develop a wearable functional biomaterial [1]. The present research aims to functionalize cellulosic fabrics (e.g. cotton and viscose) with curcumin (CUR)-loaded polycaprolactone (PCL) nanoparticles (NPs) in order to assess their potential as biofunctional garments. The NPs were produced by the flash nanoprecipitation technique in a confined impinging jet mixer. Such technology was proven to be a simple and scalable approach to produce polymeric nanoparticles; moreover it was successfully applied to curcumin encapsulation [2]. Nanoparticles were then characterized in terms of size and zeta potential by dynamic light scattering (DLS), while the loading capacity (LC%) and encapsulation efficiency (EE%) were measured by exploiting fluorescence spectroscopy. Cotton and viscose fabrics were functionalized by imbibition with the NPs suspensions and the effectiveness of the treatment was observed under wide-field fluorescence microscopy. The release properties of the nanoparticles suspensions were studied in vitro in a multicompartment rotating cell, while the curcumin release from textile support was tested ex vivo in a Franz diffusion cell using porcine skin as membrane. Furthermore, the antioxidant activity of the NPs and of the functionalized fabrics was measured by electron paramagnetic resonance spectroscopy. Curcumin loaded NPs were successfully prepared with good control of particle size and loading capacity, high stability over several days and encapsulation efficiency higher than 99%. Nanoparticles were successfully attached to the textiles material as evidenced by fluorescent imaging. The prepared materials showed an improved antioxidant activity and the capability of controlling curcumin release both in vivo and ex vivo. The present research shows the possibility of producing biofunctional materials by simple and scalable process and opens a route for a new generation of garments that can benefit people health

Peptide Fractions Obtained from Rice By- Products by Means of an Environment- Friendly Process Show In Vitro Health-Related Bioactivities

Recently, the isolation of new health-related bioactive molecules derived from agro-food industrial by-products by means of environment-friendly extraction processes has become of particular interest. In the present study, a protein by-product from the rice starch industry was hydrolysed with five commercial proteolytic enzymes, avoiding the use of solvents or chemicals. The digestion processes were optimised, and the digestates were separated in fractions with four different molecular weight ranges by using a cross-flow membrane filtration technique. Total hydrolysates and fractions were tested in vitro for a wide range of biological activities. For the first time rice-derived peptides were assayed for anti-tyrosinase, anti-inflammatory, cytotoxicity and irritation capacities. Antioxidant and anti-hypertensive activities were also evaluated. Protamex, Alcalase and Neutrase treatments produced peptide fractions with valuable bioactivities without resulting cytotoxic or irritant. Highest levels of bioactivity were detected in Protamex-derived samples, followed by samples treated with Alcalase. Based on the present results, a future direct exploitation of isolated peptide fractions in the nutraceutical, functional food and cosmetic industrial fields may be foreseen

L'herméneutique matérielle: une nouvelle phénoménologie de la connaissance

Cet article est un compte-rendu de la thèse suivante : Bruno Bachimont, Herméneutique matérielle et Artéfacture : des machines qui pensent aux machines qui donnent à penser. Critique du formalisme en intelligence artificielle, Thèse de doctorat en épistémologie sous la direction de Jean Petitot, École Polytechnique, 24 mai 1996. 354 p

Recension de : Claude Debru, Michel Morange & Frédéric Worms (dir.), Une nouvelle connaissance du vivant : François Jacob, André Lwoff & Jacques Monod (Éditions Rue d’Ulm, 2012)

Notice bibliographiqueRecension de : Claude Debru, Michel Morange & Frédéric Worms (dir.), Une nouvelle connaissance du vivant : François Jacob, André Lwoff & Jacques Monod, Paris, Éditions Rue d’Ulm, 2012. 112 p

Recension de : Janette Friedrich, Lev Vygotski : médiation, apprentissage et développement (Université de Genève, 2012)

Notice bibliographiqueRecension de : Janette Friedrich, Lev Vygotski : médiation, apprentissage et développement, Genève, Université de Genève, 2012. 138 p