title: Ultrasensitive detection of melamine based on a DNA-labeled immunosensor.
abstract: A DNA-labeled immunosensor for melamine (MEL) detection is presented which combined the exponential amplification and quantitative effect of Real-Time quantitative PCR (RT-qPCR) with the simplicity and specificity of competitive antigen-antibody reaction. An excellent linear relationship between cycle threshold (Ct) and MEL concentration in the range of 0.001-10 pg g⁻¹ was obtained with a limit of detection of 0.3 fg g⁻¹. Compared with other methods, the sensitivity of this DNA-labeled immunosensor showed a 1000-fold improvement, and was below the strictest safety limit of 1 ppm. Furthermore, the specificity was excellent and the recovery in liquid milk samples spiked with MEL was satisfactory. With the advantages of high sensitivity and a low limit of detection (LOD), this sensor is a powerful and promising tool for the detection of other small molecules besides MEL.
authors.affiliation: School of Food Science & Technology, State Key Laboratory of Food Science & Technology, Jiangnan University, Wuxi 214122, China.
authors.forename: Honghong
authors.initials: H
authors.lastname: Yin
authors.forename: Yinyue
authors.initials: Y
authors.lastname: Zhu
authors.forename: Liguang
authors.initials: L
authors.lastname: Xu
authors.forename: Hua
authors.initials: H
authors.lastname: Kuang
authors.forename: Libing
authors.initials: L
authors.lastname: Wang
authors.forename: Chuanlai
authors.initials: C
authors.lastname: Xu
mesh_terms: D000818:Animals; D000937:Antigen-Antibody Reactions; D015374:Biosensing Techniques; D004247:DNA / Q000737:chemistry* / Q000276:immunology; D005506:Food Contamination / Q000032:analysis; D057230:Limit of Detection; D008892:Milk / Q000737:chemistry; D014227:Triazines / Q000737:chemistry / Q000302:isolation & purification*
chemical_list: D014227:Triazines; D004247:DNA; C011907:melamine