Benjamin Kruppke

The unique properties of silica, such as biocompatibility and the ability to promote cell growth, demonstrate favorable results in different applications such as drug delivery, biomedical applications, and tissue engineering (TE). Electrospinning has emerged as a method for creating a substrate with a high surface area and structural resemblance to natural extracellular matrices. A common method of fabricating silica nanofibers (SNFs) for TE involves hybrid silica/ polymer nanofibers, which require calcination to remove the polymer and obtain pure silica. This study aimed to use the sol‐gel precursor tetraethyl orthosilicate (TEOS) to fabricate pure SNFs through electrospinning and investigate calcination's effect on their morphology, thermal behavior, mechanical properties, wettability, and porosity. The findings indicated that the calcination process reduced Young's modulus, wettability, and porosity, which may influence the applications of SNFs in TE. Nanofibrous mats with high Young's modulus can play a crucial role in providing mechanical support for tissue repair. Additionally, high porosity and wettability can facilitate cell attachment and growth by improving nutrient and oxygen transport to the cells. This study provides valuable insights into the potential use of pure SNFs and highlighted the effects of heat treatment on their properties.

Biopolymer hydrogels have become an important group of biomaterials in experimental and clinical use. However, unlike metallic or mineral materials, they are quite sensitive to sterilization. The aim of this study was to compare the effects of gamma irradiation and supercritical carbon dioxide (scCO2) treatment on the physicochemical properties of different hyaluronan (HA)- and/or gelatin (GEL)-based hydrogels and the cellular response of human bone marrow-derived mesenchymal stem cells (hBMSC). Hydrogels were photo-polymerized from methacrylated HA, methacrylated GEL, or a mixture of GEL/HA. The composition and sterilization methods altered the dissolution behavior of the biopolymeric hydrogels. There were no significant differences in methacrylated GEL release but increased methacrylated HA degradation of gamma-irradiated samples. Pore size/form remained unchanged, while gamma irradiation decreased the elastic modulus from about 29 kPa to 19 kPa compared to aseptic samples. HBMSC proliferated and increased alkaline phosphatase activity (ALP) particularly in aseptic and gamma-irradiated methacrylated GEL/HA hydrogels alike, while scCO2 treatment had a negative effect on both proliferation and osteogenic differentiation. Thus, gamma-irradiated methacrylated GEL/HA hydrogels are a promising base for multi-component bone substitute materials.

As a glycerol-based polyester, poly(glycerol azelaic acid) has shown great potential for biomedical applications, such as tissue engineering.