A ratiometric fluorescent nanoprobe for signal amplification monitoring of intracellular telomerase activity

Recent advances in optical biosensing and imaging of telomerase activity and relevant signal amplification strategies

“…Ma et al also developed a FRET strategy based on QD and Cy5 for monitoring of telomerase. 40 The LOD was calculated to be 45 cells per μL for HeLa cells, and the telomerase activity for each HeLa cell was determined to be 6.25 × 10 −9 IU.…”

Fluorescent nano- and microparticles for sensing cellular microenvironment: past, present and future applications

“…7b ). 217 The nanoprobe comprised a core–shell streptavidin-modified cadmium selenide/zinc sulphide core–shell (CdSe/ZnS) QD (QDs SA ) ( λ ex = 235 nm; λ em = 600 nm), which was a functionalized with a telomerase primer (TP) and a signal switching sequence (SS), which was designed to form a hairpin filament complementary to telomerase. To obtain a sensing system, the SS was labelled at its 5′ end with cyanine 5 (Cy5) ( λ ex = 630 nm; λ em = 665 nm) that acted as an FL acceptor.…”