A hand-held fiber-optic implement for the site-specific delivery of photosensitizer and singlet oxygen.
A hand-held fiber-optic implement for the site-specific delivery of photosensitizer and singlet oxygen.
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DOI：
10.1111/j.1751-1097.2011.00971.x
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发表时间：
2011-11
影响因子：
3.3
通讯作者：
Greer A
中科院分区：
文献类型：
--
作者：
Mahendran A;Kopkalli Y;Ghosh G;Ghogare A;Minnis M;Kruft BI;Zamadar M;Aebisher D;Davenport L;Greer A
我们构建了一种光纤装置，其内部流动三线态氧并外部产生单线态氧，在(Z)-1,2-二烷氧基乙烯间隔基团处引起反应，在反应性二氧杂环丁烷中间体断裂时释放脱镁叶绿酸敏化剂。可以使用吸收光谱和荧光光谱来操作该装置并观察敏化剂的光释放。我们证明了当探针尖端与辛醇或亲脂性介质接触时敏化剂光释放的偏好。在辛醇中测得的一级光裂解速率常数为 1.13 h−1，其中染料解吸不伴随再吸附。当探针尖端接触水溶液时，光释放效率低下，因为即使在共价乙烯间隔键已断裂后，大多数染料仍吸附在探针尖端上。观察到的游离敏化剂在亲脂介质中的稳定性是合理的，即使它是焦脱镁叶绿酸——一种在羧酸基团上带有对甲酰基苯甲醇取代基的衍生物。在辛醇或脂质体系中，我们发现染料不易水解为焦脱镁叶绿酸-a，否则在二元甲醇-水体系 (9:1) 中，在 pH 值低于 2 或高于 8 时观察到 pH 效应。
We have constructed a fiber optic device that internally flows triplet oxygen and externally produces singlet oxygen, causing a reaction at the (Z)-1,2-dialkoxyethene spacer group, freeing a pheophorbide sensitizer upon the fragmentation of a reactive dioxetane intermediate. The device can be operated and sensitizer photorelease observed using absorption and fluorescence spectroscopy. We demonstrate the preference of sensitizer photorelease when the probe tip is in contact with octanol or lipophilic media. A first-order photocleavage rate constant of 1.13 h−1 was measured in octanol where dye desorption was not accompanied by readsorption. When the probe tip contacts aqueous solution, the photorelease was inefficient because most of the dye adsorbed on the probe tip, even after the covalent ethene spacer bonds have been broken. The observed stability of the free sensitizer in lipophilic media is reasonable even though it is a pyropheophorbide-a derivative that carries a p-formylbenzylic alcohol substituent at the carboxylic acid group. In octanol or lipid systems, we found that the dye was not susceptible to hydrolysis to pyropheophorbide-a, otherwise a pH effect was observed in a binary methanol-water system (9:1) at pH below 2 or above 8.
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影响因子：
3.1
作者：
Garcia, Angelica M.;Alarcon, Emilio;Lissi, Eduardo
通讯作者：
Lissi, Eduardo
影响因子：
3.3
作者：
Fu, YX;Sima, PD;Kanofsky, JR
通讯作者：
Kanofsky, JR
影响因子：
3.1
作者：
Delanaye, L;Bahri, MA;Hoebeke, M
通讯作者：
Hoebeke, M
影响因子：
3.3
作者：
Ben-Dror, Shimshon;Bronshtein, Irena;Ehrenberg, Benjamin
通讯作者：
Ehrenberg, Benjamin
影响因子：
3.4
作者：
Bronshtein, I;Afri, M;Ehrenberg, B
通讯作者：
Ehrenberg, B