The present disclosure provides methods and reagents for improving nanopore-based analyses of polymers. Specifically, the disclosure provides a method of analyzing a polymer that includes a polymer analyte that contains an end domain that has at least one charged moiety. The disclosure also provides a method of increasing the interaction rate between a polymer analyte and a nanopore, wherein the polymer analyte contains an end domain that has at least one charged moiety. The disclosure also provide compositions for use with the described methods, including adapter compositions that contain charged moieties, such as phosphate or sulfate groups, and that are configured to being linked to an polymer analyte domain.