title: Luminol/antibody labeled gold nanoparticles for chemiluminescence immunoassay of carcinoembryonic antigen.
abstract: A facile strategy by loading luminol and secondary antibody on gold nanoparticles (Au NPs) was described in the present work. The as-prepared luminol/antibody labeled Au NPs conjugates (LAAu NPs) were used as the chemiluminescent probe for the detection of carcinoembryonic antigen (CEA) in serum. The LAAu NPs were characterized by transmission electron microscopy (TEM), UV-vis spectrophotometry (UV-vis), and chemiluminescent method. Stable and efficient chemiluminescence (CL) was obtained when luminol molecules and secondary antibodies were coimmobilized on the Au NPs by using hydrogen peroxide (H(2)O(2)) as an oxidant, horseradish peroxidase (HRP) as a catalyst, and 4-(4'-iodo)phenylphenol (IPP) as an enhancer. The LAAu NPs were further evaluated via a sandwich-type CL immunoassay of CEA in serum. In this protocol, the CEA analyte was captured by the primary antibody immobilized on the surface of magnetic beads, and then was sandwiched by the secondary antibody loaded on luminol-labeled Au NPs. The chemiluminescent intensity was proportional to the concentration of CEA over the range of 5.0x10(-10) to 5.0x10(-8) g mL(-1) and 5.0x10(-9) to 2.0x10(-8) g mL(-1) by using HRP and Co(2+) as catalysts, respectively. The present chemiluminescent immunoassay based on the luminol/antibody labeled Au NPs conjugates has offered great promise for simple, highly biocompatible, and cost-effective analysis of biological samples.
authors.affiliation: Key Laboratory of Eco-chemical Engineering, Ministry of Education, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, China. yangxiaoyan zh@126.com
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Yang
authors.forename: Yingshu
authors.initials: Y
authors.lastname: Guo
authors.forename: Aiguo
authors.initials: A
authors.lastname: Wang
mesh_terms: D000818:Animals; D055910:Antibodies, Immobilized / Q000737:chemistry* / Q000276:immunology; D015374:Biosensing Techniques; D002272:Carcinoembryonic Antigen / Q000032:analysis* / Q000097:blood / Q000276:immunology; D002417:Cattle; D006046:Gold / Q000737:chemistry*; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D008163:Luminescent Measurements / Q000379:methods*; D008165:Luminol / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D015203:Reproducibility of Results; D013194:Staining and Labeling
chemical_list: D055910:Antibodies, Immobilized; D002272:Carcinoembryonic Antigen; D008165:Luminol; D006046:Gold