Development of gelatin-alginate hydrogels for burn wound treatment

Hydrogels are interesting as wound dressing for burn wounds to maintain a moist environment. Especially gelatin and alginate based wound dressings show strong potential. Both polymers are modified by introducing photocrosslinkable functionalities and combined to hydrogel films (gel-MA/alg-MA). In one protocol gel-MA films are incubated in alg-MA solutions and crosslinked afterward into double networks. Another protocol involves blending both and subsequent photocrosslinking. The introduction of alginate into the gelatin matrix results in phase separation with polysaccharide microdomains in a protein matrix. Addition of alg(-MA) to gel-MA leads to an increased swelling compared to 100% gelatin and similar to the commercial Aquacel Ag dressing. In vitro tests show better cell adhesion for films which have a lower alginate content and also have superior mechanical properties. The hydrogel dressings exhibit good biocompatibility with adaptable cell attachment properties. An adequate gelatin-alginate ratio should allow application of the materials as wound dressings for several days without tissue ingrowth

Preparation and characterisation of a new double-sided bio-artificial material prepared by casting of poly(vinyl alcohol) on collagen

A new double-sided bio-artificial polymer material prepared by casting of poly(vinyl alcohol) (PVA) on collagen (COLL) was obtained. The single components were blended with lactic acid and glutaraldehyde as plasticiser and crosslinker agents, respectively, to change and characterise structure of both the polymers. Differential scanning calorimetry, dynamic mechanical analysis, tensile test, tear resistance test, scratch test and Fourier transform infrared spectroscopy were chosen to characterise all the prepared materials. The results showed that the additives led to the decrease of glass transition temperature, melting temperature and crystallinity with respect to raw materials. The new bio-artificial material revealed tough behaviour with yield stress, with less by half tensile strength compared to neat materials and with the strain of PVA (> 100 %). Both PVA and COLL blends and the new bio-artificial material exhibited viscoelastic features useful for being used in contact with living organism