Dipartimento di Chimica, Università di Roma Sapienza, P.le A. Moro 5, I-00185 Roma, Italy.
Dalton Trans. 2012 May 28;41(20):6112-21. doi: 10.1039/c2dt12381a. Epub 2012 Apr 5.
The photoactivity for the generation of singlet oxygen, (1)O(2), the key cytotoxic agent in the anticancer treatment known as photodynamic therapy (PDT), and the fluorescence response of the highly electron-deficient tetrakis(thiadiazole)porphyrazines of formula [TTDPzM] (M = Mg(II)(H(2)O), Zn(II), Al(III)Cl, Ga(III)Cl, Cd(II), Cu(II), 2H(I)) were examined (c ≅ 10(-5) M) in dimethylformamide (DMF) and/or in DMF preacidified with HCl (DMF/HCl; [HCl] = 1-4 × 10(-4) M). The singlet oxygen quantum yield (Φ(Δ)) of all the compounds was determined by using a widely employed procedure based on the selective oxidation of the 1,3-diphenylisobenzofuran (DPBF), modified in part as reported. The list of the Φ(Δ) values indicates excellent photosensitizing properties for the series of compounds carrying "closed shell" metal ions, with values measured in DMF/HCl respectful of the "heavy atom effect" for the first four lighter centers, increasing in the order Mg(II) < Al(III) < Zn(II) < Ga(III). Data of Φ(Δ) concerning the unmetalated species [TTDPzH(2)], present in solution in the form of the corresponding anion TTDPz, and the Cd(II) and Cu(II) complexes are also presented and discussed. Extensive discussion is also developed on the fluorescence quantum yield values Φ(F), with data on the Mg(II) and Al(III) compounds in DMF/HCl (0.44 and 0.53, respectively) indicative of promising perspectives for applications in fluorescence imaging techniques. The Φ(F) data of the studied porphyrazine series, Φ(F)(Pz), correlate linearly with those of the homologous phthalocyaninato complexes, Φ(F)(Pc), suggesting a closely similar behaviour between the two classes of compounds. The incorporation of [TTDPzZn] into liposomes was successfully achieved following the detergent depletion method (DDM) from a mixed micellar solution by means of gel-filtration. Retention of [TTDPzZn] (~40%) in its photoactive monomeric form into liposomes is proved by absorption and fluorescence spectra, this proposing the Zn(II) complex as a promising candidate for use in PDT.
研究了式[TTDPzM]（M = Mg(II)(H(2)O)、Zn(II)、Al(III)Cl、Ga(III)Cl、Cd(II)、Cu(II)、2H(I)）的高电子缺电子四噻二唑卟嗪的生成单线态氧（1）O(2)的光活性，（1）O(2)是称为光动力疗法（PDT）的抗癌治疗中的关键细胞毒性剂，以及在二甲基甲酰胺（DMF）和/或用 HCl 预酸化的 DMF（DMF/HCl；[HCl] = 1-4×10(-4) M）中的荧光响应。所有化合物的单线态氧量子产率（Φ(Δ)）均通过使用广泛采用的基于 1,3-二苯基异苯并呋喃（DPBF）的选择性氧化的程序来确定，该程序部分根据报道进行了修改。Φ(Δ)值列表表明，带有“闭壳”金属离子的化合物系列具有出色的光敏特性，在 DMF/HCl 中测量的值符合前四个较轻中心的“重原子效应”，顺序为 Mg(II) < Al(III) < Zn(II) < Ga(III)。还提供并讨论了关于[TTDPzH(2)]未金属化物种的Φ(Δ)值，该物种以相应的阴离子TTDPz的形式存在于溶液中，以及 Cd(II)和 Cu(II)配合物。还对荧光量子产率值Φ(F)进行了广泛的讨论，并提供了 DMF/HCl 中 Mg(II)和 Al(III)化合物的数据（分别为 0.44 和 0.53），表明在荧光成像技术中有应用的有前景。研究的卟嗪系列的Φ(F)数据Φ(F)(Pz)与同系物酞菁配合物的Φ(F)(Pc)呈线性相关，表明这两类化合物具有非常相似的行为。通过凝胶过滤，用去污剂耗竭法（DDM）从混合胶束溶液中成功地将[TTDPzZn]掺入脂质体中。吸收和荧光光谱证明[TTDPzZn]（~40%）以其光活性单体形式保留在脂质体中，这表明 Zn(II)配合物是光动力疗法的有前途的候选物。
