title: A novel biosensor based on competitive SERS immunoassay and magnetic separation for accurate and sensitive detection of chloramphenicol.
abstract: The accurate and sensitive detection of chloramphenicol (CAP) is particularly imperative to public health and safety. Here, we present a novel sensor for residual CAP detection based on competitive surface-enhanced Raman scattering (SERS) immunoassay and magnetic separation. In this nanosensor, functionalized Au nanoparticles (AuNPs) were labeled with the Raman reporter molecule (e.g. 4,4'-dipyridyl). With the addition of free CAP, a competitive immune reaction was initiated between free CAP and above AuNPs for conjugating with CAP antibody-modified magnetic nanoparticles (MNPs). Instead of the solid substrate, the antibody conjugated-magnetic beads were used as supporting materials and separation tools in the present sensor. With the aid of a magnet, the mixture was removed from the supernatant for concentration effects. This caused obvious change of SERS signal intensity obtained from supernatant. The SERS signals were collected from the supernatant directly, which made the SERS measurements more stable, repeatable and reliable. The proposed SERS-based magnetic immunosensor allows us to detect CAP in a fast, selective and sensitive (1.0 pg/mL) manner over a wide concentration range ( 1-1 × 10(4)pg/mL). In addition, these results demonstrate that this immunosensor holds great potential for the detection of antibiotics in real aquatic environment, which is crucial to our life.
authors: MOE Key Laboratory of Laser Life Science & Institute of Laser Life Science, College of Biophotonics, South China Normal University, Guangzhou 510631, PR China.
authors: Kang
authors: K
authors: Yang
authors: MOE Key Laboratory of Laser Life Science & Institute of Laser Life Science, College of Biophotonics, South China Normal University, Guangzhou 510631, PR China. Electronic address: yjhu@scnu.edu.cn.
authors: Yongjun
authors: Y
authors: Hu
authors: MOE Key Laboratory of Laser Life Science & Institute of Laser Life Science, College of Biophotonics, South China Normal University, Guangzhou 510631, PR China.
authors: Ning
authors: N
authors: Dong
mesh_terms: D000900:Anti-Bacterial Agents / Q000032:analysis*; D055910:Antibodies, Immobilized / Q000737:chemistry; D015374:Biosensing Techniques / Q000191:economics / Q000379:methods*; D002701:Chloramphenicol / Q000032:analysis*; D006046:Gold / Q000737:chemistry; D007118:Immunoassay / Q000191:economics / Q000379:methods; D057230:Limit of Detection; D053768:Metal Nanoparticles / Q000737:chemistry; D011725:Pyridines / Q000737:chemistry; D013059:Spectrum Analysis, Raman / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D000900:Anti-Bacterial Agents; D055910:Antibodies, Immobilized; D011725:Pyridines; D014874:Water Pollutants, Chemical; D002701:Chloramphenicol; D006046:Gold; C034306:4,4'-bipyridyl
keywords: Chloramphenicol; Competitive; Magnetic separation; Surface-enhanced Raman scattering