A chitin nanofibril-based non-woven tissue as medical dressing: the role of bionanotechnology

Recent Developments in Chitosan-Based Micro/Nanofibers for Sustainable Food Packaging, Smart Textiles, Cosmeceuticals, and Biomedical Applications

“…Although chitosan derivatives have been applied as innovative materials for the manufacture of various cosmeceutical products, only a limited number of cosmeceutical products utilize chitosan nanofibers. To the authors’ knowledge, the only cosmeceutical product reported to utilize these nanofibers is a chitin nanofibril mask designed for use as a facial dressing for medical purposes; the nano/micropores in this product allow bioactive substances through the dressing and block microbes and contaminants from reaching the healing skin [ 92 ]. This mask has been described as a transparent, flexible, and thin film made by casting technology.…”

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“…Chitin is the most abundant second common polysaccharide found in nature after cellulose,being widely distributed in the skeletal material of crustaceans and insects as well as component of cell walls of bacteria and fungi.It differs from cellulose only for the C-2 position of the backbone,where chitin has a N-acetyl group,chitosan an amino group and cellulose an hydroxyl group (fig 12). Depending on the molecular chain orientation chitin is produced in nature in the beta,gamma and in alpha form,as the more frequent.In this last form the polymer appears organized by ordered crystalline microfibril units comprised of 18-25 polymeric chains which create a complex hierarchical architecture [61].Thus,the acetyl groups of the crystallin alpha-chitin Figure 12: Chemical formulation of cellulose compared to Chitin and chitosan structure represent essential interactive sites,necessary to connect the adjacent chitin chains via hydrogen bonds as well as by other non-bonded interactions.Consequently for example,the bundles of chitin nanofibrils determine the corresponding mechanical properties and flexibility of the final engineered non-woven tissue designed as well as the degree of deacetylation of the polymer leads to the capability of forming more or less hydrogen and covalent bonding at low pH,because of the presence of -OH and -NH2 free groups [62].When industrially produced from our group,each chitin Nanofibril' (CN)crystal is covered on its surface by around 15.000 positive electrical charges,and shows a mean dimension of 240x7x5 nm (fig 13) with a water uptake capacity of about 400 wt%,at a pH interval between 2 and 4 [63,65].Thus in water suspension,CN exhibits an interesting capacity to self-assembly natural polymers covered by negative charges as nanolignin(LN),entrapping active ingredients as glycyrrhetic acid and niacinamide into films of polylactic acid (PLA)made (fig 14) [66].Moreover CN,allowing the facility to modify its surface because of the high modulus and strength along the axes of the fiber and the capacity to self-assembly with other natural polymers entrapping different active ingredients,has shown the ability to recreate the natural arrangement of fibrous proteins in living tissues,repairing burns and skin wounds [67,68].Moreover, CN,contributes to the orientation of the chitosan/chitin nanocomposite and other macromolecules as PLA nanocomposite,increasing its strength and Young modulus of the final designed fibers(fig 15) [69,70].Probably these various characteristics could be at the base of the effectiveness to repair the skin affected by burns and wounds of tissues made by CN and its complexes [71]. At this purpose it has been shown the facility by which CN-Lignin,bound to nanostructured silver (Ag), make non-woven tissues.Moreover,the tissues have the ability to regulate the cicatrizing phenomena promoting the healing of skin wounds and its repairing activity in a shorter time.Additionally,they don't provoke side effects such as hypertrophic ...…”

“…Thus,chitin and lignin are both natural polymers that can be complexed by the gelation method to obtain nanoparticles able to entrap different active ingredients designed to make innovative biomedical healthy products. Naturally the obtained final nanoparticle properly come not only from the active ingredient selected and entrapped into the complex, but also from its morphology, size and surface charge determined by the purity and concentration of both lignin and chitin, their physicochemical characteristics and the solvent used for its extraction (63,91). However, both these polymers may have many potential applications as wound dressings and drug delivery systems depending to the different ways chitin and lignin can be combined with other biomaterials and bioingredients to construct innovative composite,biodegradable films and non-woven tissues,as reported from some of our research studies also (20)(21)(22)(63)(64)(65)(66)(67)(68)(69)(70)(71)(72)(73)(74)(75)(76)(77)(91)(92)(93).…”

Therapeutic compression materials and wound dressings for chronic venous insufficiency: A comprehensive review

“…Nanoparticles (e.g., silver, silica, gold, and platinum) have demonstrated various biological effects (e.g., antibacterial action, tissue regeneration, and cell culture (Revell, )) and thus are key materials for treating diverse diseases because of their notable antimicrobial characteristics and high ratio of surface area to volume (Abdallah et al, ). In addition, polymers such as polyvinyl alcohol, chitosan, and starch have excellent biocompatible and biodegradable properties (Daeschlein et al, ; Morganti, Del Ciotto, Carezzi, Nunziata, & Morganti, ), and are increasingly used in drug delivery, leg ulcer healing, and artificial cartilage materials because of these sought‐after renewable biological properties. Recently, new polymer manufacturing techniques have exhibited potential for application in fabricating advanced wound dressings through processes such as 3D printing and electrospinning.…”