Highly Sensitive Detection of Telomerase by Using G-Quartet DNA Binder Conjugated Polymeric Microspheres

The interests of many researchers are focused on detection of telomerase, because highly sensitive detection of telomerase enables us to detect many kinds of cancers in their early stage, and also gives us much important information about cell biology. In this study, a new method of telomerase detection using polymeric microspheres on surface plasmon resonance (SPR)-based sensors is proposed. The telomerase detection is done through highly sensitive detection of G4-DNA generated from elongation of telomere by telomerase. The microspheres possess two functions: DNA structure recognition and SPR signal amplification. Polymeric microspheres could amplify the signal due to the interaction with G4-DNA about 760-times through DNA structure recognition. The lowest detection limit of telomerase was increased 150-fold by using polymeric microspheres. This method enables the detection of telomerase that is extracted from fewer than 1 cell. The results suggest that this newly proposed assay is suitable for detection of telomerase activity due to the ultrahigh sensitivity.