Silver nanoparticle-based ultrasensitive chemiluminescent detection of DNA hybridization and single-nucleotide polymorphisms.
A new nanoparticle-based chemiluminescent (CL) method has been developed for the ultrasensitive detection of DNA hybridization. The assay relies on a sandwich-type DNA hybridization in which the DNA targets are first hybridized to the captured oligonucleotide probes immobilized on polystyrene microwells and then the silver nanoparticles modified with alkylthiol-capped oligonucleotides are used as probes to monitor the presence of the specific target DNA. After being anchored on the hybrids, silver nanoparticles are dissolved to Ag+ in HNO3 solution and sensitively determined by a coupling CL reaction system (Ag+-Mn2+-K2S2O8-H3PO4-luminol). The combination of the remarkable sensitivity of the CL method with the large number of Ag+ released from each hybrid allows the detection of specific sequence DNA targets at levels as low as 5 fM. The sensitivity increases 6 orders of magnitude greater than that of the gold nanoparticle-based colorimetric method and is comparable to that of surface-enhanced Raman spectroscopy, which is one of the most sensitive detection approaches available to the nanoparticle-based detection for DNA hybridization. Moreover, the perfectly complementary DNA targets and the single-base mismatched DNA strands can be evidently differentiated through controlling the temperature, which indicates that the proposed CL assay offers great promise for single-nucleotide polymorphism analysis.
Liu
Cheng-Hui
CH
College of Chemistry and Environment Science, Hebei University, Baoding 071002, China.
Li
Zheng-Ping
ZP
Du
Bao-An
BA
Duan
Xin-Rui
XR
Wang
Yu-Cong
YC
D004247:DNA / Q000032:analysis* / Q000737:chemistry / Q000235:genetics*; D015342:DNA Probes / Q000737:chemistry* / Q000648:ultrastructure; D006863:Hydrogen-Ion Concentration; D008163:Luminescent Measurements / Q000379:methods*; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D012680:Sensitivity and Specificity; D012834:Silver / Q000737:chemistry*; D013696:Temperature
D015342:DNA Probes; D012834:Silver; D004247:DNA