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The main complication that may arise after surgery is the formation of adhesions. The current trend in the prevention of postoperative adhesions is the application of anti-adhesive barrier materials for the separation of wound tissue during the critical period of mesothelial repair and healing. In this work, cryogels based on pectin and chitosan were obtained by the ionic cryotropic gelation method. It was found that the Heracleum L. pectin cryogels are more elastic (73 ± 6 kPa) than the apple pectin cryogels (29 ± 11 kPa). The addition of chitosan with different physical and chemical characteristics did not significantly affect the elasticity of pectin–chitosan cryogels. The greatest swelling ability was achieved during in vivo incubation of Heracleum L. pectin cryogels and Heracleum L. pectin with reacetylated chitosan cryogels (17.1 ± 1.6 and 14.2 ± 2.0 g/g, respectively). It was found that the complete biodegradation of apple pectin cryogels occurred within 24 h of incubation in the rat abdominal cavity. Heracleum L. pectin cryogels were encapsulated in a fibrous capsule and detected in the abdominal cavity after 168 h. Maximum anti-adhesion effect was observed through the use of apple pectin cryogels (0 ± 0.5 score). Significant anti-adhesive effect was also observed through the use of apple pectin–reacetylated chitosan cryogels (1 ± 0.5 score). Due to the high anti-adhesive activity, such cryogels can be recommended for the development of a new barrier material for use in surgery. The potential anti-adhesive mechanism of apple pectin cryogels which may be attributed to a combination of barrier function and bioactivity of cryogels components was discussed.

Natural biodegradable and biocompatible polysaccharides chitosan, pectin, carrageenan and heparin were used to form thin nanostructured films. In this study using atomic force microscopy (AFM) and force spectroscopy the special characteristics of formation and structure of thin coatings were investigated, three models of the polymers interaction were proposed. Different mechanisms of polymers influence on each other in the bilayers formation were shown, coatings with different surface structure and mechanical properties were formed. The obtained data can be used for the preparation of nanostructured coatings with desired surface parameters.

Today, there is a need for the development of biomaterials with novel properties for biomedical purposes. The biocompatibility of materials is a key factor in determining its possible use in biomedicine. In this study, composite cryogels were obtained based on pectin and chitosan using ionic cryotropic gelation. For cryogel preparation, apple pectin (AP), Heracleum L. pectin (HP), and chitosan samples with different physical and chemical characteristics were used. The properties of pectin-chitosan cryogels were found to depend on the structural features and physicochemical characteristics of the pectin and chitosan within them. The addition of chitosan to cryogels can increase their mechanical strength, cause change in surface morphology, increase the degradation time, and enhance adhesion to biological tissues. Cryogels based on AP were less immunogenic when compared with cryogels from HP. Cryogels based on AP and HP were hemocompatible and the percentage of red blood cells hemolysis was less than 5%. Unlike cryogels based on HP, which exhibited moderate cytotoxicity, cryogels based on AP exhibited light cytotoxicity. Based on the results of low immunogenicity, light cytotoxicity data as well as a low level of hemolysis of composite cryogels based on AP and chitosan are biocompatible and can potentially be used in biomedicine. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 547-556, 2017.

Optimal weight ratios for the preparation of lactoferrin (LF), N-succinyl chitosan (SCh) and galactomannan (GM)-based polyelectrolyte complexes (PEC) were determined. Soluble PEC were obtained using solutions of biopolymers: lactoferrin (2 mg/ml), N-succinyl chitosan (8 mg/ml) and galactomannan (16 mg/ml) in 0.15 M NaCl, pH 6.5 ± 0.1, under normal conditions at a weight ratio of 1:1 1:2 and 1:3 LF:GM; 1:1, 1:2, 1:3 and 1:4 LF:SCh; 1:3:2 and 1:2:3 LF:SCh:GM. Using the method of heat treatment below the temperature of protein denaturation from the soluble complexes were formed stable biopolymer particles which have size characteristics of 250–400 nm, regular spherical shape, a negative zeta potential of 12–17 mV and good storage stability. The load of lactoferrin in the particles was 76–87%. Yield of freeze dried particles was 70–80%. The obtained particles could eventually be used for the targeted transport of biologically active substances.

Today, there is a need for the development of biomaterials with novel properties for biomedical purposes. The biocompatibility of materials is a key factor in determining its possible use in biomedicine. In this study, composite cryogels were obtained based on pectin and chitosan using ionic cryotropic gelation. For cryogel preparation, apple pectin (AP), Heracleum L. pectin (HP), and chitosan samples with different physical and chemical characteristics were used. The properties of pectin-chitosan cryogels were found to depend on the structural features and physicochemical characteristics of the pectin and chitosan within them. The addition of chitosan to cryogels can increase their mechanical strength, cause change in surface morphology, increase the degradation time, and enhance adhesion to biological tissues. Cryogels based on AP were less immunogenic when compared with cryogels from HP. Cryogels based on AP and HP were hemocompatible and the percentage of red blood cells hemolysis was less than 5%. Unlike cryogels based on HP, which exhibited moderate cytotoxicity, cryogels based on AP exhibited light cytotoxicity. Based on the results of low immunogenicity, light cytotoxicity data as well as a low level of hemolysis of composite cryogels based on AP and chitosan are biocompatible and can potentially be used in biomedicine. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 547-556, 2017.

6 páginas, 4 figuras., The complex process of supercontinuum generation (SG) is known to be exploitable for designing spatially coherent white light sources emitting light simultaneously in the ultraviolet, visible, and infrared ranges. Herein the first natural material able to generate in laboratory conditions a supercontinuum similar to those known from man-made photonic crystal fibers is described. The ability resides in siliceous 20–50 cm long spicules of the glass sponge Sericolophus hawaiicus. By shedding into the spicules optical peak intensities ranging from 1 to 100 TW cm−2 the generation of a SG is revealed. The SG involves wavelengths between 650 and 900 nm and shows a maximum spectral spread for excitation at a wavelength of 750 nm. It is hypothesized that the SG is favored by spicules being a biocomposite that incorporates together isotopically pure biogenic silica (δ30Si = −3.28) and 15.2 ± 1.3 μg N-acetyl-glucosamine (chitin) per mg of silica. The internal organization of these spicules is distinguished by a solid silica core with a 1 μm wide axial channel as well as a highly ordered silica–chitin composite. Such a composition and organization pattern may be of potential interest for the design of low temperature synthesis of future materials for light guidance., This work was partially supported by the following research grants DFG Grant EH 394/3-1, Krüger Research School, Biohydrometallurgical Center for Strategic Elements (BHMZ) at TU Bergakademie Freiberg, BMBF within the project CryPhys Concept (03EK3029A), Germany, and a grant of the Spanish Government (CTM2015-67221-R) to M.M.