ANYL 49 |
| A quantum-dot (QD, CdSe@ZnS) based electrochemical immunoassay to detect a protein biomarker, interleukin-1á (IL-1á) will be presented. QD conjugated with anti-IL-1á antibody was used as a label in an immunorecognition event. After a complete sandwich immunoreaction among the primary IL-1á antibody (immobilized on the avidin-modified magnetic beads), IL-1á, and the QD-labeled secondary antibody, QD labels were attached to the magnetic-bead surface through the antibody-antigen immunocomplex. Electrochemical stripping analysis of the captured QDs was used to quantify the concentration of IL-1á after an acid-dissolution step. The streptavidin-modified magnetic beads and the magnetic separation platform were used to integrate a facile antibody immobilization (through a biotin/streptavidin interaction) with immunoreactions and the isolation of immunocomplexes from reaction solutions in the assay. The voltammetric response is highly linear over the range of 0.5 to 50 ng mL-1 IL 1á, and the limit of detection is estimated to be 0.3 ng mL-1 (18 pM). This QD-based electrochemical immunoassay shows great promise for rapid, simple, and cost-effective detection of protein biomarkers. |
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General Posters
7:00 PM-9:00 PM, Sunday, August 19, 2007 BCEC -- Exhibit Hall - B2, Poster
Division of Analytical Chemistry |