[http:// mfold.bioinfo.rpi.edu/ (18) ] and Visual OMP TM 7.0 (DNA Software). Visual OMP TM 7.0, which uses the Nearest Neighbor (NN) algorithm [DNA Software (19) ], was used to estimate the change in Gibb's free energy associated with hybridization of the two strands (ÁG) for the interaction between probes and targets at 45 and 55 C in 3M TMAC. IDT OligoAnalyser was used to estimate ÁG for the interaction between probes and targets using 50-mM Na + and 2-mM Mg 2+ . Each combination was tested with the heterodimer-formation function (http://eu.idtdna.com/analyzer/Applications/ OligoAnalyzer/).