Highly Sensitive Fluorescent Probes for the Quantitative Determination of Singlet Oxygen ( 1O 2)

Abstract

Singlet oxygen ( 1O 2) is an important species for oxidation in biological processes. 1O 2 is implicated in the genotoxic effect, and plays an important role in the cell-signaling cascade and in the induction of gene expression. However, the rapid detection of 1O 2 in biological environments with sufficient specificity and sensitivity is hampered by its extremely low emission probability. Here, a layer-by-layer (LbL) film of CdTe quantum dots (QDs), polymers, and ascorbate have been designed as a rapid, highly selective, and sensitive fluorescence probe for 1O2 detection. Upon reaction with 1O 2, the probe exhibits a strong photoluminescence (PL) response even at trace levels. This remarkable PL change should enable the probe to be used for 1O 2 detection in many chemical and biological systems and as an environmental sensor. © 2005 KCSNET.