SERS assay of telomerase activity at single-cell level and colon cancer tissues via quadratic signal amplification.
As an important biomarker and therapeutic target, telomerase has attracted extensive attention concerning its detection and monitoring. Recently, enzyme-assisted amplification approaches have provided useful platforms for the telomerase activity detection, however, further improvement in sensitivity is still hindered by the single-step signal amplification. Herein, we develop a quadratic signal amplification strategy for ultrasensitive surface-enhanced Raman scattering (SERS) detection of telomerase activity. The central idea of our design is using telomerase-induced silver nanoparticles (AgNPs) assembly and silver ions (Ag(+))-mediated cascade amplification. In our approach, each telomerase-aided DNA sequence extension could trigger the formation of a long double-stranded DNA (dsDNA), making numerous AgNPs assembling along with this long strand through specific Ag-S bond, to form a primary ampliﬁcation element. For secondary ampliﬁcation, each conjugated AgNP was dissolved into Ag(+), which can effectively induce the 4-aminobenzenethiol (4-ABT) modified gold nanoparticles (AuNPs@4-ABT) to undergo aggregation to form numerous "hot-spots". Through quadratic ampliﬁcations, a limit of detection down to single HeLa cell was achieved. More importantly, this method demonstrated good performance when applied to tissues from colon cancer patients, which exhibits great potential in the practical application of telomerase-based cancer diagnosis in early stages. To demonstrate the potential in screening the telomerase inhibitors and telomerase-targeted drugs, the proposed design is successfully employed to measure the inhibition of telomerase activity by 3'-azido-3'-deoxythymidine.
State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, College of Biology, Hunan University, Changsha 410082, China.
Muling
M
Shi
State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, College of Biology, Hunan University, Changsha 410082, China. Electronic address: zhengjing2013@hnu.edu.cn.
Jing
J
Zheng
State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, College of Biology, Hunan University, Changsha 410082, China.
Changhui
C
Liu
State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, College of Biology, Hunan University, Changsha 410082, China.
Guixiang
G
Tan
State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, College of Biology, Hunan University, Changsha 410082, China.
Zhihe
Z
Qing
State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, College of Biology, Hunan University, Changsha 410082, China.
Sheng
S
Yang
Department of Anesthesiology, The Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha 410013, China.
Jinfeng
J
Yang
State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, College of Biology, Hunan University, Changsha 410082, China.
Yongjun
Y
Tan
State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, College of Biology, Hunan University, Changsha 410082, China; School of Chemistry and Biological Engineering, Changsha University of Science and Technology, Changsha 410004, China. Electronic address: Yangrh@pku.edu.cn.
Ronghua
R
Yang
D003110:Colonic Neoplasms / Q000201:enzymology*; D004789:Enzyme Activation; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006367:HeLa Cells; D006801:Humans; D053768:Metal Nanoparticles; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012834:Silver / Q000737:chemistry*; D013059:Spectrum Analysis, Raman / Q000295:instrumentation*; D020349:Surface Plasmon Resonance / Q000295:instrumentation*; D019098:Telomerase / Q000032:analysis / Q000378:metabolism*
D012834:Silver; D019098:Telomerase
Cancer tissue; Quadratic amplification; Silver nanoparticle (AgNP); Surface-enhance Raman Spectroscopy; Telomerase activity