Universal peroxidase-like strategy for sensitive glucose detection in complex matrix

Glucose detection in complex matrix such as physiological fluids and drinks can provide useful information guide for people. However, traditional detection methods toward complex matrix suffer from the impurity interference or complex pretreatments. So, it is important to exploit a universal and sensitive glucose detection strategy in complex matrix. In this work, a cascade catalytic scheme based on peroxidase-like MBs@MIL-100(Fe)@Ag (MMA) is developed for sensitive glucose detection in complex solution. Using 3,3′,5,5′-tetramethylbenzidine (TMB) as an indicator, MMA can trigger catalytic cascade reactions for specific glucose sensing. In particular, the peroxidase-like MIL-100(Fe) serves as both the catalysis unit and enrichment unit. Oxidation state of TMB (oxTMB) can be effectively and specifically enriched by MIL-100(Fe) to exclude the interference of undesired impurities and macromolecules, which is suitable for complex sample matrix including colored soda and saliva. In addition, utilizing the peroxidase-like activity of MIL-100(Fe) for self-clean, the residual indicator molecules can be degraded, resulting in the recyclable use of MMA.