The
complex of hypocrellin B (HB) with aluminium was synthesized to improve the water solubility and red absorption
of the parent pigment. The complexation of HB with Al3+ resulted in the formation of a complex with 1 : 1 Al(III) : HB stoichiometry (Al3+–HB) measured by molar ratio and continuous variation methods, respectively. The
structure of this complex has been characterized by UV-Vis, IR, 1H NMR and elemental analysis data. Compared with
HB, the complex possesses excellent solubility in water; in addition, the absorption wavelength of Al3+–HB shifts
bathochromically into the phototherapeutic window (600–900 nm). The generation of active oxygen species, including
the superoxide radical anion (O2•−) and singlet oxygen (1O2), by Al3+–HB photosensitization was observed.
The efficiency of O2•− generation by Al3+–HB was twice as much as that of HB. Under our experimental conditions, the
rate of O2•− generation by Al3+–HB was about 2.3 μM min−1 measured by the cytochrome c reduction method using 578
nm light. The quantum yield of singlet oxygen (1O2) was 0.23 in DMSO determined by the 9,10-DPA (diphenylanthracene)
photobleaching experiments. These results suggest that the new complex possesses an enhanced type I process but
a decreased type
II process as compared
with hypocrellin B.
为了提高母体色素的
水溶性和红色吸收性,我们合成了hypocrellin B(HB)与铝的络合物。HB 与 Al3+ 复合后形成了 1 : 1 的 Al(III) 复合物:通过摩尔比和连续变化法分别测量了 HB 的
化学计量(Al3+-HB)。通过紫外可见光、红外光谱、1H NMR 和元素分析数据对该复合物的结构进行了表征。与 HB 相比,该复合物在
水中具有良好的溶解性;此外,Al3+-HB 的吸收波长呈浴色移动,进入光疗窗口(600-900 nm)。实验观察到 Al3+-HB 光敏作用生成了活性氧,包括超氧自由基阴离子(O2--)和单线态氧(1O2)。 Al3+-HB 生成 O2--的效率是 HB 的两倍。在我们的实验条件下,使用 578 纳米波长的光,通过细胞色素 c 还原法测得 Al3+-HB 产生 O2 的速率约为 2.3 μM min-1。通过 9,10-DPA(二苯基
蒽)光漂白实验测定,单线态氧(1O2)在
二甲基亚砜中的量子产率为 0.23。这些结果表明,与
次黄嘌呤 B 相比,新复合物的 I 型过程增强,但 II 型过程减弱。