Hybridization of complementary strand and single-base mutated oligonucleotides detected with an on-line acoustic wave sensor†

Abstract

The hybridization of a biotinylated 25-mer oligonucleotide probe with complementary, non-complementary and single-base mutated 25-mer targets at the liquid–solid (neutravidin-modified) interface of a thickness-shear mode acoustic wave device was studied. The sensor was incorporated into an on-line configuration capable of both variable flow and stop-flow experiments. Under ambient temperature conditions different signals were obtained for the complementary and non-complementary cases. At higher temperatures, the former system exhibits behaviour characteristic of the production of intermediate duplexes which are decomposed by the re-introduction of buffer solution. The use of these conditions allows the distinction of binding events involving a set of single-base mutated 25-mers. Different responses were obtained depending on both the nature of the instigated mismatch in base pairing and on the location of mutation.