Hollow Hierarchical Cu-BTC as Nanocarriers to Immobilize Lipase for Electrochemical Biosensor

Enzyme sensors have been widely applied to the detection of various analytes, However, poor stability under harsh conditions and difficulty to recycle restrict the application of the enzyme. We utilizing the advantage of the designable structure of MOFs synthesized hollow hierarchical porous Cu-BTC with cuprous oxide (Cu 2 O) as the template to immobilize the enzyme, which significantly increased the enzyme loading capacity, about 1.89 times that of microporous Cu-BTC. Compared to the free CRL, the HH-Cu-BTC immobilized CRL (CRL@HH-Cu-BTC) demonstrated excellent pH resistance, thermal stability, and recyclability, since the HH-Cu-BTC with hollow hierarchical porous provided a great microenvironment for CRL. CRL@HH-Cu-BTC was eventually applied for the electrochemical biosensor of diphenyl ether pesticide (nitrofen). The fabricated biosensors showed a linear detection range of (0–78 µM), a LOD of 1.15 µM, and great recovery, with the advantages of low cost, fast response, and convenient device assembly.