HpD肿瘤定位组份的时间分辨荧光光谱研究

STUDY OF TIME-RESOLVED FLUORESCENCE SPECTRA ON TUMOR LOCALIZING FRACTION OF HpD

采用微微秒激光作激发源的时间相关单光子计数系统测量了血卟啉衍生物的肿瘤定位组分(TLF)在缓冲液中不同阳离子表面活性剂浓度下的荧光衰减波形I(t)和时间分辨光谱I(λ,t).

The fluorescence decay I(t) and time-resolved fluorescence spectra I(λ,t) of the tumor localizing fraction (TLF) of HpD in buffer at different concentrations of cationic surfactant were measured by a time correlated single photon counting system with a mode-locked laser as the excitation source. The fluorescence decay could be fitted by two or three exponential components, with fluorescence lifetime constants of 0.7, 3 and 15ns, respectively. The contribution of the different components to the fluorescence spectra were evaluated by setting three different times windows from the fluorescence peak, according to the measured fluorescence lifetime constants. On the basis of our measurements an energy transfer mechanism, related to the configuration state of the TLF/CTAB concentration of Hp moieties in TLF polymeric chains, exists in TLF, depending on the TLF/CTAB concentration. The fluorescence spectra of TLF in buffer are simply superimposed by the emission of the different components, indication no evident interaction among the chromophorcs.