Highly sensitive detection of protein with aptamer-based target-triggering two-stage amplification.
Highly sensitive detection of proteins is essential to biomedical research as well as clinical diagnosis. However, so far most detection methods rely on antibody-based assays and are usually laborious and time-consuming with poor sensitivity. Here, we develop a simple and sensitive method for the detection of a biomarker protein, platelet-derived growth factor BB (PDGF-BB), based on aptamer-based target-triggering two-stage amplification. With the involvement of an aptamer-based probe and an exponential amplification reaction (EXPAR) template, our method combines strand displacement amplification (SDA) and EXPAR, transforming the probe conformational change induced by target binding into two-stage amplification and distinct fluorescence signal. This detection method exhibits excellent specificity and high sensitivity with a detection limit of 9.04 × 10(-13) M and a detection range of more than 5 orders of magnitude, which is comparable with or even superior to most currently used approaches for PDGF-BB detection. Moreover, this detection method has significant advantages of isothermal conditions required, simple and rapid without multiple separation and washing steps, low-cost without the need of any labeled DNA probes. Furthermore, this method might be extended to sensitive detection of a variety of biomolecules whose aptamers undergo similar conformational changes.
Single-Molecule Detection and Imaging Laboratory, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China.
Zhen-zhu
ZZ
Zhang
Chun-yang
CY
Zhang
D052157:Aptamers, Nucleotide / Q000737:chemistry*; D000077214:Becaplermin; D015342:DNA Probes / Q000737:chemistry; D005456:Fluorescent Dyes / Q000737:chemistry; D021141:Nucleic Acid Amplification Techniques; D020574:Proto-Oncogene Proteins c-sis / Q000032:analysis*; D013050:Spectrometry, Fluorescence
D052157:Aptamers, Nucleotide; D015342:DNA Probes; D005456:Fluorescent Dyes; D020574:Proto-Oncogene Proteins c-sis; D000077214:Becaplermin