Optical, Electrical and Surface Plasmon Resonance Methods for Detecting Telomerase Activity

摘要

Three different sensing platforms for the analysis ofntelomerase activity in human cells are described. Onensensing platform involves the label-free analysis of thentelomerase activity by a field-effect-transistor (FET) device.nThe telomerase-induced extension of a primer associatednwith the gate of the FET device, in the presence of thennucleotide mixture dNTPs, alters the gate potential, andnthis allows the detection of telomerase extracted from 65n( 10 293T (transformed human embryonic kidney) cellsμL. The second sensing platform involves the opticalndetection of telomerase using CdSe/ZnS quantum dotsn(QDs). The telomerase-stimulated telomerization of thenprimer-functionalized QDs in the presence of the nucleotidenmixture dNTPs results in the synthesis of the G-richntelomeres. The stacking of hemin on the self-organizednG-quadruplexes found on the telomers results in thenelectron transfer quenching of the QDs, thus providingnan optical readout signal. This method enables the detectionnof telomerase originating from 270 ( 20 293T cellsμL. The third sensing method involves the amplifiednsurface plasmon resonance (SPR) detection of telomerasenactivity. The telomerization of a primer associated withnAu film-coated glass slides, in the presence of telomerasenand the nucleotide mixture (dNTPs), results in the formationnof telomeres on the surface, and these alter thendielectric properties of the surface resulting in a shift innthe SPR spectrum. The hybridization of Au NPs functionalizednwith nucleic acids complementary to the telomerenrepeat units with the telomeres amplifies the SPR shiftsndue to the coupling between the local plasmon of the NPsnand the surface plasmon wave. This method enables thendetection of telomerase extracted from 18 ( 3 293Tncells/μL.