This paper will discuss the biocompatibility and dynamic fatigue properties of polystyrene-b-polyisobutylene-b-polystyrene thermoplastic elastomer with 30 wt % polystyrene (SIBS30), an emerging FDA-approved biomaterial. SIBS30 is a very soft, transparent biomaterial resembling silicone rubber, with superior mechanical properties. Using the hysteresis method adopted for soft biomaterials, the dynamic fatigue properties of SIBS30 were found to be between those of polyurethane and silicone rubber, with fatigue life twice as long as that of silicone. Under single load testing (SLT, 1.25 MPa), SIBS30 displayed less than half the dynamic creep compared to silicone, both in air and in vitro (37 degrees C, simulated body fluid). Hemolysis and 30- and 180-day implantation studies revealed excellent biocompatibility of the new biomaterial. The results presented in this paper indicate that, in comparison with silicone rubber, SIBS30 has similar biocompatibility and superior dynamic fatigue properties.

Epilobium angustifolium L. is applied as an antiseptic agent in the treatment of skin diseases. However, there is a lack of information on human skin penetration of active ingredients with antioxidative potential. It seems crucial because bacterial infections of skin and subcutaneous tissue are common and partly depend on oxidative stress. Therefore, we evaluated in vitro human skin penetration of fireweed ethanol-water extracts (FEEs) by determining antioxidant activity of these extracts before and after penetration study using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and Folin–Ciocalteu methods. Microbiological tests of extracts were done. The qualitative and quantitative evaluation was performed using gas chromatography-mass spectrometry (GC-MS) and high-performance liquid chromatography (HPLC-UV) methods. The in vitro human skin penetration using the Franz diffusion chamber was assessed. The high antioxidant activity of FEEs was found. Gallic acid (GA), chlorogenic acid (ChA), 3,4-dihydroxybenzoic acid (3,4-DHB), 4-hydroxybenzoic acid (4-HB), and caffeic acid (CA) were identified in the extracts. The antibacterial activities were found against Serratia lutea, S. marcescens, Bacillus subtilis, B. pseudomycoides, and B. thuringiensis and next Enterococcus faecalis, E. faecium, Streptococcus pneumoniae, Pseudomonas aeruginosa, and P. fluorescens strains. In vitro penetration studies showed the penetration of some phenolic acids and their accumulation in the skin. Our results confirm the importance of skin penetration studies to guarantee the efficacy of formulations containing E. angustifolium extracts.