Photosensitized oxidation of hypoxanthine and xanthine by aluminum phthalocyanine tetrasulfonate. Role of the alkylating quinone 2,5-dichloro-diaziridinyl-1,4-benzoquinone.
Photosensitized oxidation of hypoxanthine and xanthine by aluminum phthalocyanine tetrasulfonate. Role of the alkylating quinone 2,5-dichloro-diaziridinyl-1,4-benzoquinone.
复制标题
酞菁四磺酸铝光敏氧化次黄嘌呤和黄嘌呤。
DOI：
10.1111/j.1751-1097.2008.00389.x
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发表时间：
2008
影响因子：
3.3
通讯作者：
Kumar,Ajay
中科院分区：
文献类型：
--
作者：
Alegria,AntonioE;Inostroza,Yaritza;Kumar,Ajay
在2，5-二氯-二氮丙啶基-1，4-苯醌（AZDClQ）和次黄嘌呤（HX）存在下，在675 nm处对含有四磺酸铝酞菁（AlPcS 4）的氮饱和水溶液进行光照射，产生氧化的HX衍生物、黄嘌呤（X）和尿酸（UA）。AZDClQ半醌、X和UA的浓度随着照射时间的增加以HX为代价而增加。如果在相同条件下但不存在AZDClQ的情况下发生光解，则检测到几乎可忽略的HX分解以及非常少量的X。在存在或不存在HX和pH 5.5的情况下，含有醌、DNA和AlPcS 4的厌氧样品光解后，添加小牛胸腺DNA产生醌-DNA共价加合物。然而，如果HX存在，则检测到更大量的醌-DNA加合物。这里提出的结果可以应用于低氧组织的光动力治疗，如实体肿瘤，在高HX浓度的条件下，其中I型途径可能比单线态氧的产生更重要。
Photoirradiation of nitrogen‐saturated aqueous solutions containing aluminum phthalocyanine tetrasulfonate (AlPcS4) at 675 nm in the presence of 2,5‐dichloro‐diaziridinyl‐1,4‐benzoquinone (AZDClQ) and hypoxanthine (HX) produces the oxidized HX derivatives, xanthine (X) and uric acid (UA). Concentrations of the AZDClQ semiquinone, X and UA increase at the expense of HX with an increase in irradiation time. Almost negligible decomposition of HX, as well as very low amounts of X, are detected if photolysis occurs under identical conditions but in the absence of AZDClQ. Addition of calf‐thymus DNA produces quinone‐DNA covalent adducts after photolysis of anaerobic samples containing quinone, DNA and AlPcS4, in the presence or absence of HX and at pH 5.5. However, larger amounts of quinone‐DNA adducts are detected if HX is present. The results presented here could have applications in the photodynamic treatment of hypoxic tissues such as solid tumors, under conditions of high HX concentration, where Type‐I pathways could be more important than singlet oxygen generation.