title: A fluorescent aptasensor based on DNA-scaffolded silver-nanocluster for ochratoxin A detection.
abstract: The selective detection of ultratrace amounts of ochratoxin A (OTA) is extremely important for food safety since it is one of the most toxic and widespread mycotoxin. Here we develop a signal-on fluorescent biosensor for detection of OTA based on fluorescent DNA-scaffolded silver-nanocluster (AgNCs), structure-switching of anti-OTA aptamer (Ap) and magnetic beads (MBs), and demonstrate its feasibility in the application of detecting OTA in real samples of wheat. The method exhibits superior sensitivity with a detection limit as low as 2 pg/mL OTA with high specificity. To the best of our knowledge, this is the first attempt to detect OTA based on DNA-scaffolded AgNCs, which possesses relatively high fluorescence quantum yield and photostability with regard to traditional organic dyes and quantum dots. Moreover, combined with the merits of MBs and aptamer, the proposed sensor has many advantages such as fabrication easiness, operation convenience, low cost, and being fast and portable, which may represent a promising path toward routine OTA control.
authors.affiliation: Department of Pharmaceutical Analysis, Faculty of Pharmacy, Fujian Medical University, Fuzhou 350108, Fujian, China.
authors.forename: Jinghua
authors.initials: J
authors.lastname: Chen
authors.affiliation: Department of Pharmaceutical Analysis, Faculty of Pharmacy, Fujian Medical University, Fuzhou 350108, Fujian, China.
authors.forename: Xi
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Department of Pharmaceutical Analysis, Faculty of Pharmacy, Fujian Medical University, Fuzhou 350108, Fujian, China.
authors.forename: Shuxian
authors.initials: S
authors.lastname: Cai
authors.affiliation: Department of Pharmaceutical Analysis, Faculty of Pharmacy, Fujian Medical University, Fuzhou 350108, Fujian, China.
authors.forename: Dongzhi
authors.initials: D
authors.lastname: Wu
authors.affiliation: Department of Pharmaceutical Analysis, Faculty of Pharmacy, Fujian Medical University, Fuzhou 350108, Fujian, China.
authors.forename: Mei
authors.initials: M
authors.lastname: Chen
authors.affiliation: The Ministry of Education Key Laboratory of Biopesticide and Chemical Biology, and College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, Fujian, China. Electronic address: wshyyl@sina.com.cn.
authors.forename: Shihua
authors.initials: S
authors.lastname: Wang
authors.affiliation: The Ministry of Education Key Laboratory of Biopesticide and Chemical Biology, and College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, Fujian, China. Electronic address: 1601225385@qq.com.
authors.forename: Jing
authors.initials: J
authors.lastname: Zhang
mesh_terms: D052157:Aptamers, Nucleotide / Q000737:chemistry*; D015374:Biosensing Techniques / Q000379:methods; D005456:Fluorescent Dyes / Q000737:chemistry*; D005506:Food Contamination / Q000032:analysis; D057230:Limit of Detection; D009183:Mycotoxins / Q000032:analysis*; D049329:Nanostructures / Q000737:chemistry*; D009793:Ochratoxins / Q000032:analysis*; D012834:Silver / Q000737:chemistry*; D014908:Triticum / Q000737:chemistry / Q000382:microbiology*
chemical_list: D052157:Aptamers, Nucleotide; D005456:Fluorescent Dyes; D009183:Mycotoxins; D009793:Ochratoxins; C025589:ochratoxin A; D012834:Silver
keywords: DNA-scaffolded silver-nanocluster; Fluorescent aptasensor; Magnetic beads; OTA; Structure-switching