Novel bone growth-stimulating interfaces are designed via surface modification of titanium (Ti) surfaces using the bioceramic CaCO 3 in the vaterite phase, Ca-crosslinked alginate hydrogel, or a blend of these two materials with an active enzyme, alkaline phosphatase (ALP), as an osteoinductive component. The surface morphology and chemistry of the engineered surfaces are investigated using scanning electron microscopy, atomic force microscopy, and Fourier transform infrared spectroscopy, while the vaterite crystal fraction within the inorganic phase of the different coating types is determined by X-ray diffraction. The functionality of the osteoconductive assembled bioceramic-hydrogel interface on Ti surface in regard with an active ALP payload is verified by the surface ALP loading and its activity. The methods of loading of ALP onto a Ti surface, adsorption versus coprecipitation, have a significant influence on the activity of immobilized ALP amount. The osteoblasts cultivated on the engineered surfaces functionalized with ALP exhibit a higher viability. The proposed composite materials with an active surface and a high mineral content represent an attractive biointerface for tissue engineering.
The aim of this study was to formulate silica and alginate hydrogels for immobilization of β-glucosidase. For this purpose, enzyme kinetics in hydrogels were determined, activity of immobilized enzymes was compared with that of free enzyme, and structures of silica and alginate hydrogels were characterized in terms of surface area and pore size. The addition of polyethylene oxide improved the mechanical strength of the silica gels and 68% of the initial activity of the enzyme was preserved after immobilizing into tetraethyl orthosilicate-polyethylene oxide matrix where the relative activity in alginate beads was 87%. The immobilized β-glucosidase was loaded into glass-silicon-glass microreactors and catalysis of 4-nitrophenyl β-d-glucopyranoside was carried out at various retention times (5, 10, and 15 min) to compare the performance of silica and alginate hydrogels as immobilization matrices. The results indicated that alginate hydrogels exhibited slightly better properties than silica, which can be utilized for biocatalysis in microfluidic platforms.
These results revealed that usage of the microreactors has considerable potential to efficiently obtain bioactive GluA-free aglycons from various plant-derived β-glucuronides for pharmaceutical applications.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.