Thus we have shown an efficient excimer formation in the duplexes of tandem probes with fcDNA target.
Decrease of excimer fluorescence as a result of hybridization with mmDNA in comparison to hybridization with fcDNA was typical for both tandem series (Figures 4(a) and 4(b)).
Discrimination of Mismatch in DNA by Thermal Denaturation with Excimer Fluorescence Detection Method.
The reduction of excimer fluorescence followed the order G<A<T<C insertion.
Single nucleotide deletion may be expected to be either a factor that brings together adjoining termini of tandem components consequently leading to increase of excimer fluorescence or a factor that can disturb a favorable excimer conformation.
We can conclude that the designed tandem probes can be used as instruments of insertion and deletion detection in DNA target using the method of registration of excimer fluorescence change.
The shortening of [C.sub.5]-[C.sub.6] and elongation of [C'.sub.5]-[C'.sub.6], as shown in Figure 2(a), suggest an exciton state evolving to a charge transfer state (i.e., excimer) after 100 fs.
At larger distances, the excited system evolves to an excimer characterized by charge transfer; at shorter distances, the strong intermolecular interaction may change the redox potential of bases and result in charge recombination, which leads to two neutral molecules.
Our simulation indicates that from the minimum, the (C*C) excimer has to overcome a barrier of 0.9 eV to reach the funnel.
In the dimerization mechanism, an evolution of "ultrafast exciton" to "charge transfer excimer" and ultimately leading to formation of CPD was reported.
An "excimer state" results from charge transfer that occurs when the interbase distance is 3.8 A in this simulation.
The TD-DFT calculation yields a 0.2 eV barrier between the minimum of [S.sub.1] and CI, indicating a relatively stable excimer in [pi]-stacked cytosines system, which lessens the effectiveness of internal conversion compared to thymine excimer, which has a barrierless pathway from [S.sub.1] to CI.