Different Dimensional Sensing Devices Based On Mn-ZnS Quantum Dots For Detection And Recognition Of Saccharide

Mn-ZnS quantum dots(Mn-ZnS QDs)is a new optical nanoprobe,which have unique photophysical properties and stable optical signals.Thanks to the good optical and biocompatibility,QDs are widely used in the construction of biosensors.Although the Mn-ZnS QDs has been widely used in the field of biomolecular recognition,the research on the different signal channel is still at its primary stage.Based on the different signal channels of phosphorescence,fluorescence and resonance light scattering of Mn-ZnS QDs,three different saccharide sensors have been developed.The main contents are listed as below.(1)We used the room temperature phosphorescence(RTP)of Mn-ZnS QDs as signal,bronic acid substitued viologen(BBV)was used as receptor.A phosphorescent sensor of fructose has been developed.Mn-ZnS QDs and BBV electrostatically attracted each other to form Mn-ZnS QDs/BBV nanohybrids,which quenched the RTP of Mn-ZnS QDs via photoinduced electron transfer(PIET).When fructose exists in the system,the fructose bonded with BBV to form an anionic borate,which deprives BBV from the QDs,thereby restoring the RTP.Under the favourable conditions,the method shows detection range of 0.05to 1 mmol/L,the detection limit is 0.01 mmol/L.(2)We used Mn-ZnS QDs as phosphorescence and fluorescence signal,BBV as the saccharide recognition receptor,thus developed a single-material two-dimensional saccharide array sensor.The sensor is capable of identifying six kinds of saccharides,they are D-fructose,D-glucose,D-galactose,D-mannose,L-sorbose and sucrose respectively,it can also discriminate different concentrations of saccharides.(3)We used Mn-ZnS QDs as phosphorescence,fluorescence and resonance light scattering signals,the positively-charged poly(diallyldimethylammonium chloride)(PDC)as receptor.A single material three-dimensional mucopolysaccharide array sensor of Mn-ZnS QDs/PDC nanocomposite(Mn-ZnS~+QDs)was constructed.The sensor can identify four mucopolysaccharides(heparin sulfate,hyaluronic acid,dermin sulfate and chondroitin sulfate)and different concentrations of mucopolysaccharide.