A High Sensitive And Specific Qds Fret Bioprobe For Mnase

摘要

We used CdSe/ZnS quantum dots-ssDNA-fluorescent dye conjugates as bioprobes to detect micrococcal nuclease with high specificity and sensitivity, and further utilized the bioprobe to monitor the micrococcal nuclease activity in the culture medium of Staphylococcus aureus by fluorescence microscopy.rnLuminescent semiconductor quantum dots (QDs) have attracted widespread attention in diverse research areas in the past two decades. Compared to traditional organic dyes and fluorescent proteins, QDs have some advantages such as high emission quantum yield, narrow and symmetric emission and so on, which make them excellent donors in fluorescence resonance energy transfer (FRET) processes. Luminescent QD-FRET bioprobes have been used to investigate the interactions between enzymes and substrates, for example, nuclease and nucleic acid. FRET between CdSe/ZnS QDs and dyes have been used to probe the activity of DNase and DNA polymerase. These results have indicated that QD-FRET probes could be effective nuclease sensors. Here we show that such probes can even be used for quantitative determination of nuclease providing a well-defined limit of detection. We further applied these probes in a real sample to show its application under realistic diagnostic assay conditions.