title: Engineered "hot" core-shell nanostructures for patterned detection of chloramphenicol.
abstract: In this study, we described a novel method for highly sensitive and specific detection of chloramphenicol (CAP) based on engineered "hot" Au core-Ag shell nanostructures (Au@Ag NSs). Cy5-labeled DNA aptamer was embedded between the Au and Ag layers as a signal generator and target-recognition element, to fabricate uniform Au@Ag NSs with unexpected strong and stable SERS signals. The presented CAP can specifically bind to the DNA aptamer by forming an aptamer-CAP conjugate, and cause greatly decreased SERS signals of Au@Ag NSs. By using this method, we were able to detect as low as 0.19 pg mL(-1) of CAP with high selectivity, which is much lower than those previously reported biosensors. Compared with the other SERS sensors that attached a dye in the outer layer of nanoparticles, this method exhibits excellent sensitivity and has the potential to significantly improve stability and reproducibility of SERS-based detection techniques.
authors.affiliation: National Center of Meat Quality & Safety Control, College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, China. Electronic address: ywj1103@njau.edu.cn.
authors.forename: Wenjing
authors.initials: W
authors.lastname: Yan
authors.affiliation: National Center of Meat Quality & Safety Control, College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Longping
authors.initials: L
authors.lastname: Yang
authors.affiliation: Quality and Safety Assessment Research Unit, Agricultural Research Service, USDA, Athens, GA 30605, USA.
authors.forename: Hong
authors.initials: H
authors.lastname: Zhuang
authors.affiliation: National Center of Meat Quality & Safety Control, College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Haizhou
authors.initials: H
authors.lastname: Wu
authors.affiliation: National Center of Meat Quality & Safety Control, College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, China. Electronic address: nau_zjh@njau.edu.cn.
authors.forename: Jianhao
authors.initials: J
authors.lastname: Zhang
mesh_terms: D052157:Aptamers, Nucleotide / Q000737:chemistry; D015374:Biosensing Techniques / Q000379:methods*; D002701:Chloramphenicol / Q000302:isolation & purification*; D006046:Gold / Q000737:chemistry; D053768:Metal Nanoparticles / Q000737:chemistry; D057145:Nanoshells / Q000737:chemistry*; D049329:Nanostructures / Q000737:chemistry*; D012834:Silver / Q000737:chemistry; D013059:Spectrum Analysis, Raman
chemical_list: D052157:Aptamers, Nucleotide; D012834:Silver; D002701:Chloramphenicol; D006046:Gold
keywords: Aptamer; Chloramphenicol; Core–shell nanostructure; Cy5 dye; SERS