Polyoxometalates as promising enzyme mimics for the sensitive detection of hydrogen peroxide by fluorometric method.

Polyoxometalates (POMs) have been proven to possess intrinsic peroxidase-like activity. However, by far, most of POMs with intrinsic peroxidase-like activity are stable at acid aqueous. Herein, we firstly utilized Na10[α-SiW9O34] with the peroxidase-like property in basic pH condition to build a CdTe quantum dots (QDs)-based fluorometric method for detection of hydrogen peroxide. In the CdTe QDs stable pH value, Na10[α-SiW9O34] can catalyze the decomposition of H2O2 into·OH radicals that could efficiently quench the fluorescence of CdTe QDs. The limit of detection in this system were 3.8 nmol/L. The RSD of detection were range from 0.88% to 2.78%. And the linear range of H2O2 is from 7.8 × 10-9 to 2.5 × 10-7 mol/L. The rate of recovery of sample addition was between 93.99% and 110.02%. The results not only built a simple, sensitive and easy handing assay but also enlarge the POMs' analytic application field.