title: Highly efficient electrogenerated chemiluminescence quenching of PEI enhanced Ru(bpy)₃²⁺ nanocomposite by hemin and Au@CeO₂ nanoparticles.
abstract: In this work, a new signal amplified strategy based on the quenching effect of hemin and Au nanoparticles decorated CeO2 nanoparticles (Au@CeO2 NPs) for ultrasensitive detection of thrombin (TB) is reported for the first time. Herein, the poly(ethylenimine) (PEI) enhanced Ru(bpy)3(2+) nanocomposite was implemented by direct chemical polymerization, which could provide the desirable enhanced initial ECL signal. Furthermore, the detection aptamer of thrombin (TBA 2) was immobilized on Au@CeO2 NPs to form TBA 2/Au@CeO2 conjugates. Then, the G-rich DNA of TBA 2 sequence could fold into a G-quadruplex structure to embed hemin to obtain the quenching probe of hemin/TBA 2/Au@CeO2 conjugates. In the presence of target TB, the sandwiched structure could be formed between capture aptamer (TBA 1), TB and hemin/TBA 2/Au@CeO2 conjugates, thereby resulting in a proportional quenching in ECL response with TB, due to the quenching of both hemin and Au@CeO2 NPs. As a result, the signal-off aptasensor showed a wider linear range response from 10(-13) to 10(-8) M with lower detection limit of 0.03 pM.
authors.affiliation: Key Laboratory of Luminescence and Real-Time Analytical Chemistry, Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China.
authors.forename: Lin-Ru
authors.initials: LR
authors.lastname: Hong
authors.affiliation: Key Laboratory of Luminescence and Real-Time Analytical Chemistry, Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China.
authors.forename: Ya-Qin
authors.initials: YQ
authors.lastname: Chai
authors.affiliation: Key Laboratory of Luminescence and Real-Time Analytical Chemistry, Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China.
authors.forename: Min
authors.initials: M
authors.lastname: Zhao
authors.affiliation: Key Laboratory of Luminescence and Real-Time Analytical Chemistry, Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China.
authors.forename: Ni
authors.initials: N
authors.lastname: Liao
authors.affiliation: Key Laboratory of Luminescence and Real-Time Analytical Chemistry, Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China. Electronic address: yuanruo@swu.edu.cn.
authors.forename: Ruo
authors.initials: R
authors.lastname: Yuan
authors.affiliation: Key Laboratory of Luminescence and Real-Time Analytical Chemistry, Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China. Electronic address: yingzhuo@swu.edu.cn.
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhuo
mesh_terms: D052158:Aptamers, Peptide / Q000737:chemistry; D015374:Biosensing Techniques; D055664:Electrochemical Techniques; D054856:G-Quadruplexes; D006046:Gold; D006427:Hemin / Q000737:chemistry*; D006801:Humans; D057230:Limit of Detection; D049449:Luminescence; D053768:Metal Nanoparticles / Q000737:chemistry*; D053761:Nanocomposites / Q000737:chemistry; D011094:Polyethyleneimine / Q000737:chemistry; D013917:Thrombin / Q000737:chemistry / Q000302:isolation & purification*
chemical_list: D052158:Aptamers, Peptide; D006427:Hemin; D006046:Gold; D011094:Polyethyleneimine; D013917:Thrombin
keywords: Aptasensor; Au@CeO(2) nanoparticles; Electrochemiluminescence; Hemin; Quenching; Thrombin