Porous Membrane Electrode for Quantitative Detection of Toxins

There is a need for a simple, portable, quantitative method to monitor the presence of Harmful Algal Blooms. Electrochemical detection offers some advantages for analysis, but traditional sensors are not practical for routine field use. Adapting colorimetric immunoassays on porous, flow-through electrodes can provide a means for rapid, low-cost, portable quantitative environmental analysis. This concept will be demonstrated in Phase I with a novel conductive, porous-membrane immunosensor for domoic acid. Antibodies will be attached to the electrode surface for capture of domoic acid and domoic acid-horseradish peroxidase conjugate. The immunoassay response will be measure using hydrogen peroxide and 3,3,5,5-tetramethylbenzidine as the enzyme comparison of the sample signal to a calibration curve. The porous design of the electrode allows assays to be performed quickly, simply and accurately. Phase I will focus on: 1. Production of conductive, porous membranes with a layer of antibody attached to the conductive surface. 2. Demonstration of electrochemical detection of domoic acid using these membranes. Phase II will incorporate the prototype membrane electrode and assay into a portable, low-cost, automated potentiostat that will be designed.