A novel biosensor based on boronic acid functionalized metal-organic frameworks for the determination of hydrogen...

In this work, we report a durable and sensitive H₂O₂ biosensor based on boronic acid functionalized metal-organic frameworks (denoted as MIL-100(Cr)-B) as an efficient immobilization matrix of horseradish peroxidase (HRP). MIL-100(Cr)-B features a hierarchical porous structure, extremely high surface area, and sufficient recognition sites, which can significantly increase HRP loading and prevent them from leakage and deactivation. The H₂O₂ biosensor can be easily achieved without any complex processing. Meanwhile, the immobilized HRP exhibited enhanced stability and remarkable catalytic activity towards H₂O₂ reduction. Under optimal conditions, the biosensor showed a fast response time (less than 4s) to H₂O₂ in a wide linear range of 0.5-3000μM with a low detection limit of 0.1μM, as well as good anti-interference ability and long-term storage stability. These excellent performances substantially enable the proposed biosensor to be used for the real-time detection of H₂O₂ released from living cells with satisfactory results, thus showing the potential application in the study of H₂O₂-involved dynamic pathological and physiological process.