Synchronous fluorescence determination of protein with functionalized CdS nanoparticles as a fluorescence probe Original Research Article

Nanometer-sized fluorescent particles have been successfully synthesized. A synchronous fluorescence method, with high sensitivity and selectivity, has been developed for rapid determination of protein with functionalized CdS as a fluorescence probe. When Δλ=260 nm, maximum synchronous fluorescence is produced at 274 nm at pH 7.0. Under optimal conditions, the calibration graphs are linear over the range 0.1–3.0 μg ml−1 for bovine serum albumin (BSA), 0.1–11.0 μg ml−1 for γ-globulin (γ-G) and 0.1–1.4 μg ml−1 for human serum albumin (HSA), respectively. Limits of determination were 0.01 μg ml−1 for BSA, 0.019 μg ml−1 for γ-G and 0.021 μg ml−1 for HSA, respectively. The relative standard deviations of seven replicate measurements were 1.8% for 1.0 μg ml−1 BSA, 2.2% for 1.0 μg ml−1 γ-G and 2.3% for 1.0 μg ml−1 HSA.