Cyclodextrin supramolecular inclusion-enhanced pyrene excimer switching for highly selective detection of RNase H.

Here, we report a novel fluorescence method for the highly selective and sensitive detection of RNase H by combining the use of a dual-pyrene-labeled DNA/RNA duplex with supramolecular inclusion-enhanced fluorescence. Initially, the probe is in the "off" state due to the rigidness of the double-stranded duplex, which separates the two pyrene units. In the presence of RNase H, the RNA strand of the DNA/RNA duplex will be hydrolyzed, and the DNA strand transforms into a hairpin structure, bringing close the two pyrene units which in turn enter the hydrophobic cavity of a γ-cyclodextrin. As a result, the pyrene excimer emission is greatly enhanced, thereby realizing the detection of RNase H activity. Under optimal conditions, RNase H detection can be achieved in the range from 0.08 to 4 U/mL, with a detection limit of 0.02 U/mL. Image 1 • A novel pyrene excimer switching-based fluorescence method was developed for the highly selective detection of RNase H. • The sensor exhibited high selectivity both in an ideal solution and in complex biological samples. • The developed sensor is suitable for evaluating screening potential agents to inhibit RNase H activity. • The proposed strategy holds the prospect for early diagnosis of diseases associated with abnormal RNase H activity. [ABSTRACT FROM AUTHOR]