During the past ten years, the DNA mimic peptide nucleic acid has inspired
the development of a variety of hybridisation-based methods for detection,
quantification, purification and characterisation of nucleic acids. Most of
these methods have taken advantage of the very favourable DNA and RNA hybr
idisation properties of peptide nucleic acids combined with the unique prop
erties and opportunities offered by peptide chemistry. Within the past year
, significant progress in in situ hybridisation technology has been achieve
d, which has resulted, in particular, in reliable and sensitive methods for
detection of bacteria in clinical samples, as well as in environmental sam
ples. Furthermore, applications of the polymerase chain reaction clamping m
ethod have been expanded, and novel ways of exploiting complexes of peptide
nucleic acids with double-stranded DNA, such as double duplex invasion com
plexes and PD loops, have been developed.