Immunosensor for detection of Yersinia enterocolitica based on imaging ellipsometry.
An immunosensor for the detection of pathogens was developed using imaging ellipsometry (IE) as a detection method. Yersinia enterocolitica was selected as the target pathogen in this study. A gold surface deposited with a self-assembled layer of 11-mercaptoundecanoic acid (11-MUA) was used as a substrate. For the fabrication of the immunosensor, protein G spots were made on the substrate using an inkjet-type microarrayer, and monoclonal antibody (Mab) was adsorbed onto the protein G spots. Deposition of each layer onto the substrate was confirmed by the measurement of surface plasmon resonance. The ellipsometric image of the protein G spot and the Mab-adsorbed protein G spot were acquired using an off-null ellipsometry type of imaging ellipsometry system. By measuring the ellipsometric angles of the protein layers, the surface concentration of each protein layer was calculated. The change in the mean optical intensity of the protein spot to the various concentrations of Y.enterocolitica was estimated. The immunosensor using imaging ellipsometry could successfully detect Y. enterocolitica in concentrations varying from 10(3) to 10(7) cfu/mL. The proposed immunosensor system has the advantage of allowing label-free detection, high sensitivity, and operational simplicity.
Bae
Young Min
YM
Department of Chemical and Biomolecular Engineering, Sogang University, 1 Sinsu-Dong, Mapo-Gu, Seoul 121-742, Korea.
Oh
Byung-Keun
BK
Lee
Woochang
W
Lee
Won Hong
WH
Choi
Jeong-Woo
JW
D000915:Antibody Affinity; D001426:Bacterial Proteins / Q000032:analysis; D015374:Biosensing Techniques / Q000379:methods*; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D007103:Immobilization; D007118:Immunoassay / Q000295:instrumentation / Q000379:methods*; D011994:Recombinant Proteins / Q000032:analysis; D013499:Surface Properties; D015009:Yersinia Infections / Q000175:diagnosis* / Q000382:microbiology; D015008:Yersinia enterocolitica / Q000737:chemistry*
D001426:Bacterial Proteins; D011994:Recombinant Proteins