A simple colorimetric DNA detection by target-induced hybridization chain reaction for isothermal signal amplification.
A novel DNA detection method is presented based on a gold nanoparticle (AuNP) colorimetric assay and hybridization chain reaction (HCR). In this method, target DNA hybridized with probe DNA modified on AuNP, and triggered HCR. The resulting HCR products with a large number of negative charges significantly enhanced the stability of AuNPs, inhibiting aggregation of AuNPs at an elevated salt concentration. The approach was highly sensitive and selective. Using this enzyme-free and isothermal signal amplification method, we were able to detect target DNA at concentrations as low as 0.5 nM with the naked eye. Our method also has great potential for detecting other analytes, such as metal ions, proteins, and small molecules, if the target analytes could make HCR products attach to AuNPs.
Shandong Provincial Key Laboratory of Biochemical Analysis, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, People's Republic of China; Department of Chemical and Environmental Engineering, University of California, Riverside, CA 92521, USA.
Cuiping
C
Ma
Shandong Provincial Key Laboratory of Biochemical Analysis, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, People's Republic of China.
Wenshuo
W
Wang
Department of Chemical and Environmental Engineering, University of California, Riverside, CA 92521, USA. Electronic address: adani@engr.ucr.edu.
Ashok
A
Mulchandani
Shandong Provincial Key Laboratory of Biochemical Analysis, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, People's Republic of China. Electronic address: sc169@163.com.
Chao
C
Shi
D003124:Colorimetry / Q000379:methods*; D004247:DNA / Q000302:isolation & purification*; D006046:Gold / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D009693:Nucleic Acid Hybridization / Q000379:methods*; D012680:Sensitivity and Specificity
D006046:Gold; D004247:DNA
Colorimetric DNA detection; Gold nanoparticle; Hybridization chain reaction; Nanobiosensor; Signal amplification