Nishide Naoto, Miyoshi Norio
Department of Stomatology, Tatsunokuchi Houju Memorial General Hospital, 11-71 Midorigaoka, Ishikawa, 923-1226, Japan.
Life Sci. 2002 Dec 6;72(3):321-8. doi: 10.1016/s0024-3205(02)02234-8.
Recently, 4.4'-bis(1-p-carboxyphenyl-3-methyl-5-dydroxyl)-pyrazol (DRD156) has been developed as a new sensitive reagent that reacts specifically with singlet oxygen. The specificity of DRD156 for singlet oxygen in a biomimetic solution (micellar solution) and the effects of its coexistence with other reagent were examined with electron spin resonance (ESR). Singlet oxygen was generated using photosensitization reaction. The ESR spectrum of the radical derived from DRD156 after the reaction with singlet oxygen in phosphate buffered salines (PBS) was comprised of twenty-nine lines, whereas that in cetyltrimethylammonium bromide (CTAB) micelles was comprised of nine lines. Both 2,2,6,6-tetramethyl-4-piperidine (TMPD) and 1,3-diphenyl-isobenzofuran (DPBF) reduced the singlet oxygen-DRD156 signal intensity, and TMPD-mediated decrease in PBS (to 62%) was almost the same as that in CTAB micelle (to 65%). In contrast, DPBF reduced the DRD156 signal intensity more effectively in CTAB micelle (to 12%) than PBS (to 38%). These results indicate that the specificity of DRD156 for singlet oxygen is dependent on microenvironment.
最近，4,4'-双(1-对羧基苯基-3-甲基-5-羟基)-吡唑(DRD156)已被开发成为一种能与单线态氧特异性反应的新型灵敏试剂。利用电子自旋共振(ESR)研究了DRD156在仿生溶液(胶束溶液)中对单线态氧的特异性及其与其他试剂共存时的影响。通过光敏化反应产生单线态氧。在磷酸盐缓冲盐水(PBS)中，DRD156与单线态氧反应后产生的自由基的ESR谱由29条谱线组成，而在十六烷基三甲基溴化铵(CTAB)胶束中则由9条谱线组成。2,2,6,6-四甲基-4-哌啶(TMPD)和1,3-二苯基异苯并呋喃(DPBF)均降低了单线态氧-DRD156的信号强度，且TMPD介导的PBS中信号强度降低(至62%)与CTAB胶束中的降低程度(至65%)几乎相同。相比之下，DPBF在CTAB胶束中比在PBS中更有效地降低了DRD156的信号强度(CTAB胶束中降至12%，PBS中降至38%)。这些结果表明，DRD156对单线态氧的特异性取决于微环境。
