کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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869116 | 909822 | 2009 | 5 صفحه PDF | دانلود رایگان |
In this work, we report the application of novel, water-soluble fluorescent Ag clusters in fluorescent sensors for detecting cysteine, an important biological analyte. The fluorescence of poly(methacrylic acid) (PMAA)-templated Ag clusters was found to be quenched effectively by cysteine, but not when the other α-amino acids were present. By virtue of the specific response, a new, simple, and sensitive fluorescent method for detecting cysteine has been developed based on Ag clusters. The present assay allows for the selective determination of cysteine in the range of 2.5 × 10−8 to 6.0 × 10−6 M with a detection limit of 20 nM at a signal-to-noise ratio of 3. Based on the absorption and fluorescence studies, we suggested that cysteine quenched the emission by the thiol-adsorption-accelerated oxidation of the emissive Ag clusters. The present study shows a promising step toward the application of silver clusters, a new class of attractive fluorescence probes.
Journal: Biosensors and Bioelectronics - Volume 24, Issue 6, 15 February 2009, Pages 1569–1573