Photoinduced Release of Zn2+ with ZinCleav-1: a Nitrobenzyl-Based Caged Complex
Photoinduced Release of Zn2+ with ZinCleav-1: a Nitrobenzyl-Based Caged Complex
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DOI：
10.1021/ic901062n
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发表时间：
2009-09-07
影响因子：
4.6
通讯作者：
Burdette, Shawn C.
中科院分区：
文献类型：
--
作者：
Bandara, H. M. Dhammika;Kennedy, Daniel P.;Burdette, Shawn C.
笼状配合物是金属离子螯合剂，当暴露在特定波长的光下时释放分析物。本文报道了一种用于Zn2+光解破碎的笼状物zinclev -1的合成及其性质。一般的解封策略包括在配体的主链上整合一个硝基苯基，这样碳杂原子键就会被光反应劈裂。采用一种新的合成策略，即用Strecker合成方法制备了一种关键醛中间体，得到了笼状配合物。用[Zn(PAR)(2)] （PAR = 4-（2-吡啶-2-偶氮）间苯二酚）竞争性滴定测定zinclv -1对Zn2+的K-d为0.23 pM。复载子和Zn2+配合物的量子产率分别为2.4%和0.55%。从理论上计算了zinclev -1增加游离[Zn2+]的能力，并通过荧光传感器对释放的Zn2+成像进行了实际验证。游离Zn2+可能作为一种神经递质发挥作用，并在多种神经系统疾病的病理中发挥作用。研究这些生理功能仍然具有挑战性，因为Zn2+对大多数常见的光谱技术是沉默的。我们期望zinclev -1成为第一类笼状配合物，将促进生物学研究。
Caged complexes are metal ion chelators that release analytes when exposed to light of a specific wavelength. The synthesis and properties of ZinCleav-1, a cage for Zn2+, that fragments upon photolysis, is reported. The general uncaging strategy involves integrating a nitrobenzyl group on the backbone of the ligand so that a carbon-heteroatom bond is cleaved by the photoreaction. The caged complex was obtained using a new synthetic strategy involving a Strecker synthesis to prepare a key aldehyde intermediate. ZinCleav-1 has a K-d of 0.23 pM for Zn2+ as measured by competitive titration with [Zn(PAR)(2)] (PAR = 4-(2-pyridyl-2-azo) resorcinol). The quantum yield for ZinCleav-1 is 2.4% and 0.55% for the apo and Zn2+ complex, respectively. The ability of ZinCleav-1 to increase free [Zn2+] is calculated theoretically using the binding constants for the uncaged photoproducts, and demonstrated practically by using a fluorescent sensor to image the liberated Zn2+. Free Zn2+ may function as a neurotransmitter and have a role in the pathology of several neurological diseases. Studying these physiological functions remains challenging because Zn2+ is silent to most common spectroscopic techniques. We expect ZinCleav-1 to be the first in a class of caged complexes that will facilitate biological investigations.