title: A fluorescent biosensing platform based on the polydopamine nanospheres intergrating with Exonuclease III-assisted target recycling amplification.
abstract: Rapid, cost-effective, sensitive and specific analysis of biomolecules is important in the modern healthcare system. Here, a fluorescent biosensing platform based on the polydopamine nanospheres (PDANS) intergrating with Exonuclease III (Exo III) was developed. Due to the interaction between the ssDNA and the PDANS, the fluorescence of 6-carboxyfluorescein (FAM) labelled in the probe would been quenched by PDANS through FRET. While, in the present of the target DNA, the probe DNA would hybridize with the target DNA to form the double-strand DNA complex. Thus, Exo III could catalyze the stepwise removal of mononucleotides from 3'-terminus in the probe DNA, releasing the target DNA. As the FAM was released from the probe DNA, the fluorescence would no longer been quenched, led to the signal on. As one target DNA molecule could undergo a number of cycles to trigger the degradation of abundant probe DNA, Exo III-assisted target recycling would led to the amplification of the signal. The detection limit for DNA was 5 pM, which was 20 times lower than that without Exo III. And the assay time was largely shortened due to the faster signal recovery kinetics. What is more, this target recycling strategy was also applied to conduct an aptamer-based biosensing platform. The fluorescence intensity was also enhanced for the assay of adenosine triphosphate (ATP). For the Exo III-assisted target recycling amplification, DNA and ATP were fast detected with high sensitivity and selectivity. This work provides opportunities to develop simple, rapid, economical, and sensitive biosensing platforms for biomedical diagnostics.
authors.affiliation: State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, 22 Hankou Road, Nanjing 210093, China.
authors.forename: Weibing
authors.initials: W
authors.lastname: Qiang
authors.affiliation: State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, 22 Hankou Road, Nanjing 210093, China.
authors.forename: Xi
authors.initials: X
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, 22 Hankou Road, Nanjing 210093, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.affiliation: State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, 22 Hankou Road, Nanjing 210093, China.
authors.forename: Xiang
authors.initials: X
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, 22 Hankou Road, Nanjing 210093, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Li
authors.affiliation: State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, 22 Hankou Road, Nanjing 210093, China. Electronic address: xudanke@nju.edu.cn.
authors.forename: Danke
authors.initials: D
authors.lastname: Xu
mesh_terms: D000255:Adenosine Triphosphate / Q000032:analysis / Q000378:metabolism; D015374:Biosensing Techniques / Q000379:methods*; D004247:DNA / Q000032:analysis* / Q000378:metabolism; D015342:DNA Probes / Q000737:chemistry / Q000378:metabolism; D005090:Exodeoxyribonucleases / Q000378:metabolism*; D005452:Fluoresceins / Q000737:chemistry; D005456:Fluorescent Dyes / Q000737:chemistry; D007211:Indoles / Q000737:chemistry*; D057230:Limit of Detection; D054118:Nanospheres / Q000737:chemistry* / Q000648:ultrastructure; D011108:Polymers / Q000737:chemistry*; D013050:Spectrometry, Fluorescence / Q000379:methods
chemical_list: D015342:DNA Probes; D005452:Fluoresceins; D005456:Fluorescent Dyes; D007211:Indoles; D011108:Polymers; C568283:polydopamine; C024098:6-carboxyfluorescein; D000255:Adenosine Triphosphate; D004247:DNA; D005090:Exodeoxyribonucleases; C020133:exodeoxyribonuclease III
keywords: Adenosine triphosphate (ATP); Aptamer; DNA; Exonuclease III (Exo III); Polydopamine nanospheres (PDANS); Target recycling amplification