Turning an aptamer into a light-switch probe with a single bioconjugation.

ABSTRACT: We describe a method for transforming a structure-switching aptamer into a luminescent light-switch probe via a single conjugation. The methodology is demonstrated using a known aptamer for Hg(2+) as a case study. This approach utilizes a lanthanide-based metallointercalator, Eu-DOTA-Phen, whose luminescence is quenched almost entirely and selectively by purines, but not at all by pyrimidines. This complex, therefore, does not luminesce while intercalated in dsDNA, but it is bright red when conjugated to a ssDNA that is terminated by several pyrimidines. In its design, the light-switch probe incorporates a structure-switching aptamer partially hybridized to its complementary strand. The lanthanide complex is conjugated to either strand via a stable amide bond. Binding of the analyte by the

SUBMITTER: Wickramaratne TM 

PROVIDER: S-EPMC4306522 | biostudies-literature | 2015 Jan

REPOSITORIES: biostudies-literature