Comparison of the properties of compacted and porous lamellar chitosan–xanthan membranes as dressings and scaffolds for the treatment of skin lesions

Abstract

Compacted and porous lamellar membranes of xanthan (Xn) and chitosan (Ch) at mass ratios of 1 : 1 and 1.2 : 0.8 were prepared and tested to verify possible applications in the treatment of skin lesions. All membranes were prepared by complexation of the polysaccharides in solution and subsequent casting. The porous membranes were obtained by adding either Tween 80 or Pluronic F68 to the polysaccharide complexes before casting. Membranes prepared in the absence of surfactants at a mass ratio of Xn to Ch of 1 : 1 proved ideal for use as wound dressings, as they were thin (around 0.10 mm in thickness) and transparent and had low in vitro cytotoxicity to L929 cells, a tensile strength at break of 25 MPa, water absorption after 24 h of around 86 g/g and simulated body fluid absorption of 16% and adequate stability in the presence of the same solutions. Membranes prepared at the mass ratio of Xn to Ch of 1 : 1 in the presence of Pluronic F68 showed the most favorable characteristics for application as scaffolds for tissue engineering. These membranes consisted of a matrix with interconnected pores which were distributed homogeneously throughout the structure and had a thickness of 1.84 mm, high capacity for FBS uptake (around 18 g/g) and cell culture medium uptake (8.6 g/g), a loss of mass in the culture medium of 33% after 144 h, and low in vitro toxicity to L929 cells. In conclusion, membranes of Ch and Xn produced in the presence or absence of the surfactant Pluronic F68 have a high potential for use as scaffolds in tissue engineering or as dermal dressings, respectively, whereas in contrast, membranes prepared in the presence of Tween 80, regardless of the mass ratio of Xn to Ch, were very cytotoxic to L929 cells and therefore were not appropriate for any of the proposed applications. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

Characterization of the Mandible Atta Laevigata and the Bioinspiration for the Development of a Biomimetic Surgical Clamp

“…As more frequently used natural polymers are proteins (collagen, elastin and silk fibroin) and polysaccharides (chitosan, alginate, hyaluronic acid and pectin) 33,34 . The main applications of these biopolymers are in wound treatments and controllable drug release 35,36 . It is worth mentioning that the combination between two or more synthetic or natural polymers in the form of complexes or blends, makes it possible to obtain devices with improved chemical, mechanical and biological properties when compared to the isolated polymers 33,37,38 .…”

Properties of films obtained from biopolymers of different origins for skin lesions therapy

“…Polysaccharides such as chitosan (C), xanthan (X) and alginate are examples of non-toxic natural polymers used in the composition of materials for this purpose, being used alone or in combination with each other or with other compounds (Popa et al 2010;Fernandes et al 2011;Bellini et al 2012;Veiga and Moraes 2012). However, a major obstacle to their use is the variability in the characteristics of molecules resulting from different sources, which may result in changes in the properties of biomaterials obtained when these polymers are used.…”

“…This polymer is soluble in aqueous acidic solutions, resulting in structures with different dimensions and geometric configurations, such as films, particles, fibers, and gels (Santos et al 2003;Ragetly et al 2010). The polycationic nature of chitosan enables its association with polymers with negative charges such as alginate (Rodrigues et al 2008;Bueno and Moraes 2011), dextran derivatives (Fukuda et al 1978), polyesters (Silva et al 2010), silk fibers (She et al 2008), gelatin (Liu et al 2004;Yin et al 2005), and xanthan gum (Eftaiha et al 2009;Bellini et al 2012;Veiga and Moraes 2012), resulting in stable polyelectrolyte complexes. Xanthan gum is a water-soluble exopolysaccharide synthesized by Xanthomonas and is used as emulsifier, suspension stabilizer, flocculant, gelling and viscosity agent.…”

“…When compared to polysaccharides extracted directly from the natural sources, such as alginate derived from seaweed, xanthan gum has the advantage of being independent of the production site and climatic conditions, which allows its production under significantly more controlled conditions, with lower variability in the properties of material originated from different batches and, therefore, with higher quality assurance. For this reason, xanthan gum, alone or combined with other polymers, has been gaining attention in the composition of biomaterials intended for different biomedical applications, such as devices for the controlled release of drugs (Popa et al 2010;Bellini et al 2012;Veiga and Moraes 2012;Dyondi et al 2013) and probiotic bacteria (Argin et al 2014), hydrogels for bone regeneration (Izawa et al 2014), ophthalmological materials (Ceulemans et al 2002;Ludwig 2005), implants (Kumar et al 2007) and scaffolds for tissue engineering Bellini et al 2012).…”

“…The carboxyl groups in xanthan gum, when combined with the amines of chitosan, result in a microenvironment that favors the stabilization of proteins (Chellat et al 2000) and allows obtaining hydrogels (Dyondi et al 2013;Izawa et al 2014), tablets (Popa et al 2010) and films (Bejenariu et al 2008). The properties of membranes of chitosan combined with analytical grade xanthan gum in different reacting conditions were assessed in detail recently by Bellini et al (2012), which showed that these devices had appropriate characteristics for application as bioactive dermal dressings and as three-dimensional scaffolds for cell culture useful in the tissue engineering area.…”