• cadmium;
  • enzyme catalysis;
  • fluorescence;
  • glucose;
  • quantum dots
Thumbnail image of graphical abstract

Three innovative assays have been developed for the detection of the enzymatic activities of glucose oxidase (GOx) and horseradish peroxidase (HRP) by the generation of CdS quantum dots (QDs) in situ using an unconventional enzymatic reaction. By employing 1-thiob-D-glucose and sodium thiosulfate as enzymatic substrates, sulfide ions are generated which, in the presence of cadmium ions, yield fluorescent CdS nanoparticles. On page 3449, L. Saa and V. Pavlov show how the combination of GOx with HRP allows quantification of the glucose in human plasma by following the growth of the fluorescent QDs.