Nonenzymatic nucleic acid triggered ligation reactions
are attracting much attention due to their potential use
in nucleic acid analysis.1 Reactions of nucleic acids,
which are inhibited rather then triggered by their
complementary strands, can also be used in analysis.
In particular, it has been demonstrated that selective
cleavage of unbound DNA probes catalyzed by single
strand specific nucleases2 can be applied to mass spectrometric
detection of PCR amplified DNA.3 This enzymatic
approach cannot be applied to nucleic acid
analogues, for example, peptide nucleic acids (PNA)4
and heavily modified nucleic acid probes since they are
not substrates of nucleases. The other disadvantage is
that DNA desalting is required for analysis.