异硫氰酸荧光素-酚藏花红双发光磷光探针测定DNA

Determination of Trace Deoxyribonucleic Acid by using Fluorescein Isothiocyanate-phenosafranine as a Double-luminescent Phosphorescence Probe

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.

Using Pb2＋ as ion perturber,phenosafranine（PF） and fluorescein isothiocyanate（FITC） could emit strong and stable room temperature phosphorescence（RTP） signal on the filter paper,respectively.When they were mixed,the phenomenon that the RTP signal of PF and FITC enhanced significantly was found.And 1.12 ag DNA spot？1（sample volume was 0.40 μL,corresponding concentration was 2.8×10-15 g mL-1） could cause the RTP signal of both PF and FITC to enhance sharply.The content of DNA was proportional to the ΔIp of PF and FITC in the system at 634 and 659 nm.Thus,a new solid substrate room temperature phosphorimetry（SSRTP） for the determination of trace DNA was established by using FITC-PF as double-luminescent phosphorescence probe.The detection limit（LD） of this method calculated by 3Sb/k was 14 zg DNA spot-1 for PF and 18 zg DNA spot-1 for FITC,respectively,showing high sensitivity.It has been applied to the determination of trace DNA in practical samples and the analysis results were in accordance with those of fluorescence probe.The reaction mechanism of SSRTP for the determination of trace DNA was also discussed.