2,7-BHVC,a novel two-photon fluorescent probe for DNA with large two-photon excited fluorescence action cross sections,was synthesized and characterized.It emits weak two-photon fluorescence in aqueous solution while its two-photon fluorescence is strongly restored upon binding to DNA.The two-photon imaging in cell demonstrated that 2,7-BHVC can exactly label nuclear DNA.
A new two-photon fluorescence DNA probe,BMVEC,with bigger σ×Φ(1437 GM) was synthesized.The absorption titration shows that there is an interaction between BMVEC and DNA because the probe can intercalate the grooves in the double helix of DNA,which enhances its two-photon fluorescent intensity.Meanwhile the double-staining results in cancer cells by means of TPM demonstrate the exclusive nucleic labeling ability of BMVEC,and the positions and amounts of nuclei labeled by BMVEC are wholly the identical as those by DAPI.Moreover,the incident power of BMVEC is lower than that of DAPI.The results indicate that BMVEC can act as the two-photon fluorescent probe of DNA.