Olga A. Ryazanova, et. al. recently reported the synthesis and evaluation of a pheophorbide a phenazinium dye conjugate which is effective as a probe for G-quadruplex structures of nucleic acids. The fluorescence band of the aminophenazinium dye overlaps with the absorption band of pheophorbide a , resulting in the quenching of the phenazinium moiety by FRET. Both moieties in the conjugate bind to G-quadruplexes selectively with up to 50-fold emission enhancement and a 10 nm red shift with less then 2-fold enhancement in the case of duplex polynucleotides. Thanks for using our Pheophorbide a Pha-592.