1. Department of Tissue Regeneration, University of Twente, MIRA Institute for Biomedical Technology and Technical Medicine, P.O. Box 217, 7500‐AE, Enschede, The Netherlands;2. Department of Chemical and Biomolecular Engineering, Rice University, P.O. Box 1892, Houston, TX 77251‐1892, USA;3. Department of Bioengineering, Rice University, P.O. Box 1892, Houston, TX 77251‐1892, USA;4. Department of Biomaterials, Radboud University Nijmegen Medical Centre, P.O. Box 9101, 6500 HB Nijmegen, The Netherlands
Abstract:
The enzyme alkaline phosphatase (ALP) is added at different concentrations (i.e., 0, 2.5, and 10 mg · ml?1) to oligo(poly(ethylene glycol)fumarate) (OPF) hydrogels. The scaffolds are either incubated in 10 mM calcium glycerophosphate (Ca–GP) solution for 2 weeks or implanted in a rat subcutaneous model for 4 weeks. Fourier transform infrared (FTIR) spectroscopy, X‐ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and alizarin red staining show a strong ability to form minerals exclusively in ALP‐containing hydrogels in vitro. Additionally, the calcium content increases with increasing ALP concentration. Similarly, only ALP‐containing hydrogels induce mineralization in vivo. Specifically, small (≈5–20 µm) mineral deposits are observed at the periphery of the hydrogels near the dermis/scaffold interface using Von Kossa and alizarin red staining.
