以Pb2+为离子微扰剂时,酚藏花红(PF)与异硫氰酸荧光素(FITC)均能在滤纸上分别发射强而稳定的室温磷光(RTP)信号;当两者混合时,发现PF和FITC的RTP信号均显著增强;而1.12 ag DNA spot-1均使PF和FITC的RTP信号剧烈增强,在634与659 nm处PF和FITC的ΔIp与DNA含量成线性关系,据此建立了FITC-PF双发光磷光探针测定蛋白质的新方法.该方法的检出限(LD)分别为14zg DNA spot–1(PF)和18zg DNA spot–1(FITC),灵敏度高,并成功用于花蜜样品中DNA含量的测定.同时探讨了FITC-PF双发光磷光探针测定痕量DNA的反应机理.
The interaction of phenosafranine (PSF) with a glycosaminoglycans of heparin (Hep) in aqueous solution has been characterized by UV-Vis absorption spectrophotometry and cyclic voltammetry in pH 1.5 Britton-Robinson (B-R) buffer solution. The addition of Hep caused decrease of the absorbance of PSF at 532 nm and the redox peak current of PSF. The study showed that an supramolecular complex of PSF-Hep was formed because of the electrostatic attraction of negatively charged Hep with the positively charged PSF, which resulted in the decrease of the equilibrium concentration of PSF in solutions, and the decrease of the absorbance or the peak current of PSF. The stoichiometry of the Hep/PSF complex was further calculated by voltammetric data with the result of 1:1 complex.