Photoluminescence enhancement by coupling of ovalbumin and CdTe quantum dots and its application as protein probe

CdTe quantum dots were synthesized in aqueous solution using 3-Mercaptopropionic acid as stabilizing agent. Chemically reduced ovalbumin had been used to modify the surface of CdTe QDs, resulting in the enhancement of photoluminescence intensity and the blue shift of the PL peak. A new method for the determination of ovalbumin is established based on the PL changes. Under the optimal conditions, experiment results showed that the PL intensity and the shift of PL peak are both in good linear with the ovalbumin concentration in the range of 0.125-4 mu M and the detection limit was 0.03 mu M. The method is compared with the traditional UV absorption method, and shows relatively good reliability. (c) 2007 Elsevier B.V. All rights reserved.