摘要 |
The invention features compositions and methods that are useful for precisely determining the amount of one or more analytes present in a sample. In one aspect, the invention provides a composition for measuring the abundance of one or more target analytes in a sample, where the composition contains a set of detection units for each analyte fixed to a substrate (e.g.,a membrane, bead, filter, chip, polymer-based film or glass slide, or other printable surface), where each detection unit contains a discrete amount of a capture agent that specifically binds the target analyte, and the amount of capturing agent varies over the set to form a concentration gradient. |