Bioconjugation of concanavalin and CdTe quantum dots and the detection of glucose

In this paper, water-soluble CdTe/CdS quantum dots (QDs) were synthesized in aqueous solution with glutathione (GSH) as stabilizer. Glutaraldehyde was used as the coupling agent for the conjugation of QDs and concanavalin (con A). Capillary electrophoresis was used to compare the “one-step” method and “two-step” procedure for the conjugation. It was confirmed that the “two-step” approach is more preferable. The achieved bioprobe can be used for the detection of glucose. Under the optimum conditions, the relative fluorescence intensity decreased linearly with the glucose concentration in the range of 0.04–0.2 mM. The detection limit was 0.01 mM. This study provides a new trail of thought for the detection of glucose.