Fluorescence sensor for bovine serum albumin detection based on the aggregation and release of CdS QDs within CMC

Here, an efficient in vitro fluorescence biosensor for bovine serum albumin (BSA) based on the aggregation and release of CdS quantum dots (QDs) within carboxymethyl cellulose (CMC) was investigated and discussed. The aggregation of CdS QDs within CMC was prepared by electrostatic interaction. The release of CdS QDs was due to strong covalent linking between BSA and CMC, thus leading to the more favorable combination of BSA and CMC in the system with the presence of BSA. The detection of BSA was based on the quenching and recovery of fluorescence intensity in the system, which was caused by the aggregation and release of CdS QDs. An excellent linear relationship (R-2 = 0.99286) was obtained between fluorescence intensity and BSA concentration (0.05-2.00 mu M) with a detection limit of 10(-8) M. In addition, the detection method showed high selectivity towards BSA and good stability. These results suggest that the method can be utilized as an efficient and highly selective reagent for quantification of BSA for in vitro biological science.