Biosensors for Detecting Estrogen-like Molecules and Protein Biomarkers
A novel evanescent-based biosensor (Endotect™, ThreeFold Sensors, Inc.) was developed with laser-based fiber optics using fluorescent dyelabeled recombinant human estrogen receptor-α (rhERα) and hERβ as probes. A three-tiered approach evaluating various steps in the formation of the estrogen- receptor complex and its subsequent activity was developed for instrument calibration to detect estrogen mimics in biological samples, water and soil. Using this approach, binding affinities and activities of certain known estrogen mimics were determined for their use as calibrator molecules. Results indicated rhERα and rhERβ may be employed as probes to distinguish estrogen mimics with a broad range of affinities. In addition, application of the biosensor for detecting DNA-binding proteins in human tissue extracts was demonstrated. The later studies suggest the biosensor may be used as a clinical laboratory tool for assessing tumor marker proteins.
KeywordsElectrophoretic Mobility Shift Assay Estrogen Response Element Evanescent Field Human Estrogen Receptor Estrogen Receptor Protein
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