title: Colorimetric Aptasensor Based on Enzyme for the Detection of Vibrio parahemolyticus.
abstract: A simple colorimetric aptasensor system has been developed to detect Vibrio parahemolyticus. Magnetic nanoparticles (MNPs) are synthesized and conjugated with specific aptamers against target and used as capture probes. In addition, this method employs gold nanoparticles (AuNPs) as carriers of horseradish peroxidase (HRP) and aptamers, which served as signal probes. In the presence of target, a "sandwich-type" complex of AuNPs-HRP-aptamer-target-aptamer-MNPs is formed through specific recognition of aptamers and corresponding target. As a result, HRP molecules confined at the surface of the "sandwich" complexes catalyze the enzyme substrate, 3,3',5,5'-tetramethylbenzidine (TMB) and H2O2 and generate an optical signal. Under optimal conditions, the signals are linearly dependent on V. parahemolyticus concentrations from 10 to 10(6) colony-forming units (cfu)/mL in a logarithmic plot, with a limit of detection of 10 cfu/mL. Owing to AuNPs, a large amount of HRP could be loaded, resulting in an amplified signal, and the sensitivity would be improved. This strategy has the potential of being extended to the construction of simple monitor systems for a variety of biomolecules related to food safety.
authors: State Key Laboratory of Food Science and Technology, Synergetic Innovation Center of Food Safety and Nutrition, School of Food Science and Technology, Jiangnan University , Wuxi 214122, China.
authors: Shijia
authors: S
authors: Wu
authors: State Key Laboratory of Food Science and Technology, Synergetic Innovation Center of Food Safety and Nutrition, School of Food Science and Technology, Jiangnan University , Wuxi 214122, China.
authors: Yinqiu
authors: Y
authors: Wang
authors: State Key Laboratory of Food Science and Technology, Synergetic Innovation Center of Food Safety and Nutrition, School of Food Science and Technology, Jiangnan University , Wuxi 214122, China.
authors: Nuo
authors: N
authors: Duan
authors: School of Food and Biological Engineering, Jiangsu University , Zhenjiang 212013, China.
authors: Haile
authors: H
authors: Ma
authors: State Key Laboratory of Food Science and Technology, Synergetic Innovation Center of Food Safety and Nutrition, School of Food Science and Technology, Jiangnan University , Wuxi 214122, China.
authors: Zhouping
authors: Z
authors: Wang
mesh_terms: D001560:Benzidines / Q000737:chemistry; D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D003124:Colorimetry / Q000295:instrumentation / Q000379:methods*; D006046:Gold / Q000737:chemistry; D006735:Horseradish Peroxidase / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000737:chemistry; D057230:Limit of Detection; D053768:Metal Nanoparticles / Q000737:chemistry; D014736:Vibrio parahaemolyticus / Q000737:chemistry / Q000302:isolation & purification*
chemical_list: D001560:Benzidines; C021758:3,3',5,5'-tetramethylbenzidine; D006046:Gold; D006861:Hydrogen Peroxide; D006735:Horseradish Peroxidase
keywords: Vibrio parahemolyticus; colorimetric; gold nanoparticles; horseradish peroxidase; magnetic nanoparticles