title: In situ hybridization chain reaction amplification for universal and highly sensitive electrochemiluminescent detection of DNA.
abstract: In this work, we describe a new universal and highly sensitive strategy for electrochemiluminescent (ECL) detection of sequence specific DNA at the femtomolar level via in situ hybridization chain reaction (HCR) signal amplification. The DNA capture probes are self-assembled on a gold electrode. The presence of the target DNA and two hairpin helper DNAs leads to the formation of extended dsDNA polymers through HCR on the electrode surface. The in situ, HCR-generated dsDNA polymers cause the intercalation of numerous ECL indicators (Ru(phen)(3)(2+)) into the dsDNA grooves, resulting in significantly amplified ECL signal output. The proposed strategy combines the amplification power of the DNA HCR and the inherent high sensitivity of the ECL technique and enables low femtomolar detection of sequence specific DNA. The developed strategy also shows high selectivity against single-base mismatch sequences, which makes our new universal and highly sensitive HCR-based method a useful addition to the amplified DNA detection arena.
authors.affiliation: Key Laboratory of Ministry of Education on Luminescence and Real-Time Analysis, School of Chemistry and Chemical Engineering, Southwest University, Chongqing, PR China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Chen
authors.forename: Jin
authors.initials: J
authors.lastname: Xu
authors.forename: Jiao
authors.initials: J
authors.lastname: Su
authors.forename: Yun
authors.initials: Y
authors.lastname: Xiang
authors.forename: Ruo
authors.initials: R
authors.lastname: Yuan
authors.forename: Yaqin
authors.initials: Y
authors.lastname: Chai
mesh_terms: D004247:DNA / Q000032:analysis*; D015342:DNA Probes / Q000737:chemistry / Q000378:metabolism; D004566:Electrodes; D006046:Gold / Q000737:chemistry; D017403:In Situ Hybridization; D008163:Luminescent Measurements; D021141:Nucleic Acid Amplification Techniques; D011108:Polymers / Q000737:chemistry
chemical_list: D015342:DNA Probes; D011108:Polymers; D006046:Gold; D004247:DNA