A fluorescence detection of D-penicillamine based on Cu2+-induced fluorescence quenching system of protein-stabilized gold nanoclusters

In this contribution, a luminescent gold nanoclusters which were synthesized by bovine serum albumin as novel fluorescent probes were successfully utilized for the determination of D-penicillamine for the first time. Cupric ion was employed to quench the strong fluorescence of the gold nanoclusters, whereas the addition of D-penicillamine caused obvious restoration of fluorescence intensity of the Cu2+-gold nanoclusters system. Under optimum conditions, the increment in fluorescence intensity of Cu2+-gold nanoclusters system caused by D-penicillamine was linearly proportional to the concentration of D-penicillamine in the range of 2.0 x 10(-5)-2.39 x 10(-4) M. The detection limit for D-penicillamine was 5.4 x 10(-6) M. With the off-on fluorescence signal at 650 nm approaching the near-infrared region, the present sensor for D-penicillamine detection had high sensitivity and low spectral interference. Furthermore, the novel gold nanoclusters-based fluorescent sensor has been applied to the determination of D-penicillamine in real biological samples with satisfactory results. (C) 2014 Elsevier B.V. All rights reserved.