{Reference Type}: Journal Article {Title}: In vitro biosafety of pro-ecological chitosan-based hydrogels modified with natural substances. {Author}: Tyliszczak B;Drabczyk A;Kudłacik-Kramarczyk S;Rudnicka K;Gatkowska J;Sobczak-Kupiec A;Jampilek J; {Journal}: J Biomed Mater Res A {Volume}: 107 {Issue}: 11 {Year}: 11 2019 {Factor}: 4.854 {DOI}: 10.1002/jbm.a.36756 {Abstract}: Hydrogels belong to the group of materials with growing interest on the market of polymers. In this article, hydrogels based on Beetosan were obtained using ultraviolet (UV) radiation. Main component of hydrogel matrix-Beetosan-is chitosan obtained from naturally died honeybees. Such hydrogels were modified with active substances, that is, caffeine, bee pollen, Salvia officinalis (sage), and Aloe vera juice. Next, the analysis of cytotoxicity of hydrogels in relation to murine fibroblasts by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide and neutral red uptake assays were conducted. Furthermore, surface morphology, tensile strength, geometry, and roughness of hydrogels were characterized. Hydrogels did not show cytotoxicity to recommended L929 murine fibroblasts. These polymers did not affect adversely the growth and viability of these cells. Moreover, Beetosan hydrogels were characterized by flexibility as well as by diversified surface morphology that could indicate their high absorbency. Therefore these materials may be considered as useful for biomedical purposes with special emphasis on application as modern wound dressings that not only absorb wound exudate but also contain natural substances with therapeutic properties that is beneficial from the point of view of wound healing process.