Bromopyrogallol red enhanced resonance light-scattering spectroscopic determination of DNA with 5,10,15,20-tetrakis[4-(trimethylammoniumyl) phenyl]porphine

Abstract At pH 7.5 and ion strength 0.004, the intensity of resonance light-scattering (RLS) of 5,10,15,20-tetrakis[4-(trimethylammoniumyl)phenyl]prophine (TAPP) is enhanced by DNA at 434 nm. When bromopyrogallol red (BPR) coexists with DNA and TAPP, the RLS intensity of TAPP is synergetically enhanced by BPR and DNA. Based on this, a highly sensitive method for the determination of DNA was proposed with a linear range for calf thymus DNA from 2.5×10 −8 to 9.0×10 −7  mol l −1 . The method utilizes an ordinary spectrofluorometer, and has been applied to the analysis of some synthetic samples with good recoveries. The reaction mechanism is also discussed.