Bottiroli G, Freitas I, Docchio F, Ramponi R, Sacchi C A
Chem Biol Interact. 1984 Apr;49(1-2):1-11. doi: 10.1016/0009-2797(84)90048-6.
Hematoporphyrin-Derivative (HpD), a widely-used tumor-specific photosensitizer, is a complex mixture of porphyrins whose composition has yet to be clarified. This paper reports on the behaviour of HpD in saline. From a spectroscopic point of view, the fresh solution is characterized by two main absorption peaks, attributable to monomeric and dimeric forms. With aging, a new porphyrin species (NPS) appears. To define the NPS, absorption, excitation and emission spectra were measured in different conditions and time-resolved fluorescence measurements were also performed. This species exhibits an absorption/excitation peak at 405 nm, an emission peak at 575 nm and a fluorescence decay time of approximately 3.5 ns. Its formation is strongly influenced by many environmental factors: in particular, gases diluted in the solution, temperature, pH and concentration. The presence of Oxygen and a pH value outside the 6-8 range may be considered inhibiting factors. The NPS seems to be quite important in the understanding of HpD tumor-specificity, since the presence of an emission band similar to the NPS one seems to be favoured in tumor cells as compared with normal cells.
血卟啉衍生物（HpD）是一种广泛应用的肿瘤特异性光敏剂，是一种卟啉的复杂混合物，其组成尚未明确。本文报道了HpD在盐溶液中的行为。从光谱学角度来看，新鲜溶液的特征在于两个主要吸收峰，分别归因于单体和二聚体形式。随着时间推移，一种新的卟啉物种（NPS）出现。为了定义NPS，在不同条件下测量了吸收光谱、激发光谱和发射光谱，并进行了时间分辨荧光测量。该物种在405nm处有一个吸收/激发峰，在575nm处有一个发射峰，荧光衰减时间约为3.5ns。其形成受到许多环境因素的强烈影响：特别是溶液中稀释的气体、温度、pH值和浓度。氧气的存在以及pH值在6-8范围之外可被视为抑制因素。NPS似乎在理解HpD的肿瘤特异性方面相当重要，因为与正常细胞相比，肿瘤细胞中似乎更有利于出现与NPS相似的发射带。
