Highly sensitive label-free immunosensor for ochratoxin A based on functionalized magnetic nanoparticles and EIS/SPR detection |
| |
Authors: | Lucian-Gabriel ZamfirAuthor Vitae Irina GeanaAuthor Vitae Sondes BouriguaAuthor VitaeLucian RotariuAuthor Vitae Camelia BalaAuthor Vitae Abdelhamid ErrachidAuthor VitaeNicole Jaffrezic-RenaultAuthor Vitae |
| |
Affiliation: | a Department of Analytical Chemistry, University of Bucharest, 4-12 Regina Elisabeta Blvd., 030018 Bucharest, Romania b LaborQ, University of Bucharest, 4-12 Regina Elisabeta Blvd., 030018 Bucharest, Romania c Laboratoire des Sciences Analytiques, Universite Claude Bernard Lyon 1, 69622 Villeurbanne, Lyon, France |
| |
Abstract: | A label-free immunosensor for the detection of ochratoxin A (OTA) based on use of magnetic nanoparticles (MNPs) was developed. A gold electrode was modified using bovine serum albumin conjugate with a glutaraldehyde-thiolamine linker, creating a layer that prevents non-specific binding of OTA on gold. The OTA antibodies were attached to MNPs using the carbodiimide chemistry and afterwards were immobilized on the modified gold electrode using a strong magnetic field. Cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and surface plasmon resonance (SPR) were used to characterize each step in immunosensor development. The impedance variation due to the specific antibody-OTA interaction was correlated with the OTA concentration in the samples. The increase in electron-transfer resistance values was proportional to the concentration of OTA on a linear range between 0.01 and 5 ng/mL, with a detection limit of 0.01 ng/mL. SPR measurements showed a larger response range (1-50 ng/mL) with a detection limit of 0.94 ng/mL. Analytical results were in accordance with standard ELISA test kit. |
| |
Keywords: | Ochratoxin A Magnetic nanoparticles Impedimetric SPR |
本文献已被 ScienceDirect 等数据库收录! |
|