Articles that contain a solid support with a grafted chain extending from the solid support, methods of making these articles, and various uses of the articles are described. More specifically, the grafted chain has a functional group that can react with or interact with target compound. Alternatively, the functional group on the grafted chain can react with a modifying agent to provide another group that can react with or interact with the target compound. The grafted chains are attached to the solid support through a ring-opened azlactone group. The articles can be used to purify the target compound or to separate the target compound from other molecules in a sample.