Provided herein are biocompatible scaffolds and methods of preparing such bioscaffolds. The methods provide a superior high surface area, interconnected nanomacroporous bioactive glass scaffold, by combining a sol-gel process and polymer sponge replication methods. The formation of a uniformly nanoporous and interconnected macroporous bioscaffold is demonstrated using a starting material comprising a 70 mol % SiO2—30 mol % CaO glass composition as an example. The bioscaffold includes a series of open, interconnected macropores with size from 300 to 600 μm, as desired for tissue ingrowth and vascularization. At the same time, coexisting nanopores provide high-specific surface area (>150 m2/g), which is needed for enhancing the structure's degradation rate. These bioscaffolds hold promise for applications in hard tissue engineering.