pH响应两亲嵌段锌酞菁聚合物光敏剂的制备及光活性

将氨基锌酞菁（ZnTAPc）与甲基丙烯酰氯反应制备出含有不饱和双键的取代锌酞菁衍生物（MeZnAPc）,采用ATRP法将聚乙二醇单甲醚大分子引发剂（mPEG110-Br）与甲基丙烯酸（2-异丙胺基）乙酯（DPA）和MeZnAPc共聚,制得一种新型pH响应两亲嵌段锌酞菁聚合物光敏剂（PEG110-b-P（DPAn-co-MeZnAPcm））.用1HNMR,FTIR对MeZnAPc和聚合物光敏剂进行表征.UV-vis测试表明该聚合物光敏剂在pH6.0～6.5具有较好的pH响应性.以1,3-二苯基苯并呋喃（DPBF）为底物研究了该聚合物光敏剂的光催化氧化效率,结果表明其具有较高光活性.利用该聚合物光敏剂在不同pH的水溶液中对L-色氨酸进行光催化氧化实验,结果发现在pH5.5不存在胶束时,锌酞菁可以较好地分散在溶液中,并能维持较高光活性,而在pH7.4形成胶束时可以将锌酞菁很好地包裹在其内部,使其光活性大大降低.因此,这种pH响应两亲嵌段锌酞菁聚合物作为一种新型光敏剂,在光动力学治疗领域有较好的应用前景.

Synthesis and photoactivity of pH-responsive amphiphlic block polymer photosensitizer bonded zinc phthalocyanine

A zinc tetraaminophthalocyanine derivative,zinc tetra（methacryloyl moiety）aminophthalocyanine（MeZnAPc）（with a double bond） was synthesized by the reaction between zinc tetraaminophthalocyanine（ZnTAPc） and methacryloyl chloride.Atom transfer radical polymerization（ATRP） was employed as the polymerization technique to obtain a novel pH-responsive polymeric photosensitizer（PEG110-b-P（DPAn-co-MeZnAPcm）） by copolymerizing of methoxypolyethylene glycols（MPEG）（as reducing agent）,2-（isopropylamino）ethyl methacrylate（DPA） and MeZnAPc.This photosensitizer was characterized by UV-vis spectroscopy,FTIR,1H NMR,etc.The results indicated that the photosensitizer presented the well pH-responsive behavior around the pH range 6.0-6.5 and the high photoactivity to 1,3-diphenylisobenzofuran（DPBF）.The result of photocatalysis oxidation of L-tryptophan（L-Try） suggested that zinc phthalocyanine could present high photoactivity due to its dispersivity at pH 5.5 without formation of micelles,and its photoactivity decreased dramatically at pH 7.4 due to wrapping ZnTAPc into the micelles.Therefore,the novel pH-responsive polymeric photosensitizer has better application prospects in the field of photodynamic therapy.