title: Dual hairpin-like molecular beacon based on coralyne-adenosine interaction for sensing melamine in dairy products.
abstract: This study presents a novel dual hairpin-like molecular beacon (MB) for the selective and sensitive detection of melamine (MA) based on the conjugation of MA and thymine. In this protocol, the coordination between coralyne and adenosine (A) leaded a dual hairpin-like MB and the fluorophore-quencher pair is close proximity resulting in the fluorescence quenching. With the addition of MA, it conjugated with thymine in the loop part of dual hairpin-like MB by triple H-bonds, triggering the dissociation of the dual hairpin-like MB. The resulting spatial separation of the fluorophore from quencher induced the enhancement in fluorescence emission. Under the optimized conditions, the sensor exhibited a wide linear range of 8×10(-9)-1.6×10(-5) M (R(2)=0.9969) towards MA, with a low detection limit of 5 nM, approximately 4000 times lower than the Drug Administration and the US Food estimated MA safety limit. The real milk samples were also investigated with a satisfying result.
authors.affiliation: Key Laboratory of Chem-Biosensing, Anhui Province, Anhui Normal University, Wuhu 241000, PR China; Key Laboratory of Functional Molecular Solids, Anhui Province, Anhui Normal University, Wuhu 241000, PR China; College of Chemistry and Materials Science, Center for Nano Science and Technology, Anhui Normal University, Wuhu 241000, PR China; State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha 410082, PR China. Electronic address: wangyuz@mail.ahnu.edu.cn.
authors.forename: Guangfeng
authors.initials: G
authors.lastname: Wang
authors.affiliation: Key Laboratory of Chem-Biosensing, Anhui Province, Anhui Normal University, Wuhu 241000, PR China; Key Laboratory of Functional Molecular Solids, Anhui Province, Anhui Normal University, Wuhu 241000, PR China; College of Chemistry and Materials Science, Center for Nano Science and Technology, Anhui Normal University, Wuhu 241000, PR China; State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha 410082, PR China.
authors.forename: Yanhong
authors.initials: Y
authors.lastname: Zhu
authors.affiliation: Key Laboratory of Chem-Biosensing, Anhui Province, Anhui Normal University, Wuhu 241000, PR China; Key Laboratory of Functional Molecular Solids, Anhui Province, Anhui Normal University, Wuhu 241000, PR China; College of Chemistry and Materials Science, Center for Nano Science and Technology, Anhui Normal University, Wuhu 241000, PR China; State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha 410082, PR China.
authors.forename: Ling
authors.initials: L
authors.lastname: Chen
authors.affiliation: Key Laboratory of Chem-Biosensing, Anhui Province, Anhui Normal University, Wuhu 241000, PR China; Key Laboratory of Functional Molecular Solids, Anhui Province, Anhui Normal University, Wuhu 241000, PR China; College of Chemistry and Materials Science, Center for Nano Science and Technology, Anhui Normal University, Wuhu 241000, PR China; State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha 410082, PR China. Electronic address: xjzhang@mail.ahnu.edu.cn.
authors.forename: Xiaojun
authors.initials: X
authors.lastname: Zhang
mesh_terms: D000241:Adenosine / Q000737:chemistry*; D000818:Animals; D001600:Berberine Alkaloids / Q000737:chemistry*; D015374:Biosensing Techniques / Q000379:methods; D003611:Dairy Products / Q000032:analysis*; D005456:Fluorescent Dyes / Q000737:chemistry; D005504:Food Analysis / Q000379:methods*; D005506:Food Contamination / Q000032:analysis*; D006860:Hydrogen Bonding; D006863:Hydrogen-Ion Concentration; D057230:Limit of Detection; D008892:Milk / Q000737:chemistry*; D009841:Oligonucleotides / Q000737:chemistry; D011208:Powders; D012680:Sensitivity and Specificity; D013050:Spectrometry, Fluorescence / Q000379:methods; D013696:Temperature; D013941:Thymine / Q000737:chemistry; D014227:Triazines / Q000032:analysis*
chemical_list: D001600:Berberine Alkaloids; D005456:Fluorescent Dyes; D009841:Oligonucleotides; D011208:Powders; D014227:Triazines; C000666:coralyne; D000241:Adenosine; C011907:melamine; D013941:Thymine
keywords: Adenosine; Coralyne; Melamine; Molecular beacon; Triple H-bonds