Two New Preyssler‐Type Polyoxometalate‐Based Coordination Polymers and Their Application in Horseradish Peroxidase Immobilization

Enzyme immobilization is of increasing importance for biocatalysis, for which good supports are critical. Herein, two new Preyssler‐type polyoxometalate (POM)‐based coordination polymers, namely, {[Cu(H2biim)2][{Cu(H2biim)2(μ‐H2O)}2Cu(H2biim)(H2O)2]H[({Cu(H2biim)(H2O)2}0.5)2((μ‐C3HN2Cl2){Cu(H2biim)}2){Z(H2O)P5W30O110}]⋅x H2O}n (1: Z=Na, x=9; 2: Z=Ag, x=10; H2biim=2,2′‐biimidazole) were designed and synthesized. Compounds 1 and 2 exhibit the same skeletons, which contain multiple CuII complex fragments and penta‐supported {ZP5W30} (Z=Na, Ag) clusters. They were first employed to immobilize horseradish peroxidase (HRP). Results show that compounds 1 and 2 are good supports for HRP immobilization, and exhibit higher enzyme loading, lower loading times, and excellent reusability. The immobilized HRP (HRP/1 or HRP/2) was further applied to detect H2O2, and good sensitivity, wide linear range, low detection limit, and fast response were achieved. This work shows that POM‐based hybrid materials are a new kind of promising support for enzyme immobilization. Pinning down catalysts: Two new Preyssler‐type polyoxometalate‐based coordination polymers were synthesized and applied to immobilize horseradish peroxidase (HRP). These polymers exhibited higher enzyme loading, required a shorter loading time, and exhibited excellent reusability (see figure).