Capture probes immobilizable via l-nucleotide tail

Abstract

The invention provides chimeric capture probes immobilizable via an L-nucleic acid tail that can bind to a complementary L-nucleic acid in an immobilized probe. The capture probes are useful for capturing a target nucleic acid from a sample. The L-nucleic acid in the tail of the capture probe bind to the complementary L-nucleic acid in the immobilized probe with similar affinity as would otherwise equivalent D-nucleic acids. However, the L-nucleic acid of the capture probe tail and immobilized probes do not form stable duplexes with D-nucleic acids present in the in the sample containing the target nucleic acid. Binding of nucleic acids in the sample directly to immobilized probe or to the tail of the capture probe is reduced or eliminated increasing the sensitivity and/or specificity of the assay.