The present invention provides magnetic macroporous polymeric hybrid scaffolds for supporting and enhancing the effectiveness of bionanocatalysts (BNC). The novel scaffolds comprise cross-linked water-insoluble polymers and an approximately uniform distribution of embedded magnetic microparticles (MMP). The cross-linked polymer comprises polyvinyl alcohol (PVA) and optionally additional polymeric materials. The scaffolds may take any shape by using a cast during preparation of the scaffolds. Alternatively, the scaffolds may be ground to microparticles for use in biocatalytic reactions. Alternatively, the scaffolds may be shaped as beads for use in biocatalyst reactions. Methods for preparing and using the scaffolds are also provided.