| abstract |
The present invention provides methods and compositions directed toward assays of a broad range of analytes using specific targeting chemicals that bind to the analytes. The assays are founded on the use of coded assay articles to which the targeting chemicals are attached. Additionally the codes are such that they are interrogated and determined in real time. The target is analyzed as to identity, presence and quantity in real time. The methods and compositions of the invention are highly suitable for use in high-complexity multiplexed assay systems. All the methods and compositions are based on assay article that includes an optical substrate to which the chemical is bound, and in which is disposed at least one diffraction grating. The grating provides an output optical signal when illuminated by an incident light signal which is indicative of the code in the substrate. In general, coded assay article or sets thereof are employed in assay methods, including multiplexed assay methods, according to which a sample is contacted with an article or a set, and any analytes that bind to the attached chemical are identified according to the code, detected and/or quantitated. |