Cubeddu R, Ramponi R, Taroni P, Canti G, Ricci L, Supino R
C.E.Q.S.E.-C.N.R., Istituto di Fisica del Politecnico, Milano, Italy.
J Photochem Photobiol B. 1990 Jun;6(1-2):39-48. doi: 10.1016/1011-1344(90)85072-5.
Time-gated fluorescence spectroscopy was performed on the tumour-localizing fraction (TLF) of haematoporphyrin derivative (HPD) incorporated into cells. Three different cell lines were incubated with 20 and 5 micrograms ml-1 of TLF for various time periods; they were then washed and resuspended in buffer. Fluorescence decay measurements and time-integrated and time-gated spectra were then obtained from the cell suspensions. Similar experiments were repeated using HPD containing 60% of the active material. The experimental results show a modification of the emission spectra for both drugs depending on the incubation time; this modification is more significant for the TLF. In particular, the emission peak observed in aqueous solution at 615 nm is shifted to 630 nm as a consequence of incorporation into cells, and the gated spectra indicate that the fluorescence emission is mainly related to monomers and unfolded polymeric chains. The ratio between the intensities of the two peaks depends on the relative amount of the TLF; the peak at 615 nm is more pronounced for HPD. The results obtained seem to indicate that both the composition of the drug and the metabolic properties of the biological environment strongly influence the uptake process and the fluorescence behaviour of the incorporated sensitizer.
对掺入细胞中的血卟啉衍生物（HPD）的肿瘤定位部分（TLF）进行了时间分辨荧光光谱分析。将三种不同的细胞系分别与20微克/毫升和5微克/毫升的TLF孵育不同时间；然后洗涤细胞并将其重悬于缓冲液中。接着从细胞悬液中获得荧光衰减测量值以及时间积分光谱和时间分辨光谱。使用含有60%活性物质的HPD重复进行类似实验。实验结果表明，两种药物的发射光谱都会根据孵育时间发生变化；这种变化对TLF更为显著。特别是，在水溶液中于615纳米处观察到的发射峰，由于掺入细胞而移至630纳米，并且时间分辨光谱表明荧光发射主要与单体和未折叠的聚合物链有关。两个峰的强度之比取决于TLF的相对含量；对于HPD，615纳米处的峰更为明显。所获得的结果似乎表明，药物的组成和生物环境的代谢特性都会强烈影响掺入的敏化剂的摄取过程和荧光行为。
