title: A versatile nanomachine for the sensitive detection of platelet-derived growth factor-BB utilizing a G-quadruplex-selective iridium(III) complex.
abstract: The novel iridium(III) complex 1 was found to be highly selective for G-quadruplex DNA, and was employed for the development of a versatile nanomachine. In the nanomachine, the single-stranded DNA (ssDNA) oligonucleotide ON1 hybridizes with the hairpin DNA oligonucleotide ON2, leading to the formation of a 5'-recessed double-stranded DNA (dsDNA) structure and the simultaneous release of a G-rich DNA sequence, which folds into a G-quadruplex motif that is recognized by complex 1. Upon the addition of Exo III, the dsDNA substrate is digested leading to the liberation of ON1 ssDNA, which enters a new cycle of the nanomachine. This nanomachine was successfully used to detect PDGF-BB by combination with a simple pre-procedure module, and exhibited a linear response between luminescence intensity and PDGF-BB concentration in the range of 10 to 300pM (R(2)=0.992), with a limit of detection for PDGF-BB of 10pM. This assay was highly selective for PDGF-BB over other proteins, and exhibited potential use in biological sample analysis. Moreover, the versatility of the nanomachine was demonstrated by adapting the nanomachine for the detection of thrombin by simply changing the pre-procedure module.
authors.affiliation: College of Chemistry and Pharmaceutical Sciences, Qingdao Agricultural University, Qingdao 266109, China; Department of Chemistry, Hong Kong Baptist University, Kowloon Tong, Hong Kong, China. Electronic address: lulihua2012@hotmail.com.
authors.forename: Lihua
authors.initials: L
authors.lastname: Lu
authors.affiliation: Department of Chemistry, Hong Kong Baptist University, Kowloon Tong, Hong Kong, China.
authors.forename: Zhifeng
authors.initials: Z
authors.lastname: Mao
authors.affiliation: State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao, China.
authors.forename: Tian-Shu
authors.initials: TS
authors.lastname: Kang
authors.affiliation: State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao, China. Electronic address: duncanleung@umac.mo.
authors.forename: Chung-Hang
authors.initials: CH
authors.lastname: Leung
authors.affiliation: Department of Chemistry, Hong Kong Baptist University, Kowloon Tong, Hong Kong, China. Electronic address: edmondma@hkbu.edu.hk.
authors.forename: Dik-Lung
authors.initials: DL
authors.lastname: Ma
mesh_terms: D001483:Base Sequence; D000077214:Becaplermin; D015374:Biosensing Techniques / Q000379:methods*; D056831:Coordination Complexes / Q000737:chemistry*; D004247:DNA / Q000737:chemistry; D004277:DNA, Single-Stranded / Q000737:chemistry; D054856:G-Quadruplexes; D006801:Humans; D007495:Iridium / Q000737:chemistry*; D057230:Limit of Detection; D049449:Luminescence; D008163:Luminescent Measurements / Q000379:methods*; D020574:Proto-Oncogene Proteins c-sis / Q000097:blood*
chemical_list: D056831:Coordination Complexes; D004277:DNA, Single-Stranded; D020574:Proto-Oncogene Proteins c-sis; D000077214:Becaplermin; D007495:Iridium; D004247:DNA
keywords: G-quadruplex; Iridium(III) complex; Luminescent; Nanomachine; PDGF-BB