两种典型双光子 pH 荧光探针的理论研究。

A theoretical investigation of two typical two-photon pH fluorescent probes.

机构信息

State Key Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin University, Changchun, China.

出版信息

Photochem Photobiol. 2013 Mar-Apr;89(2):300-9. doi: 10.1111/php.12015. Epub 2012 Dec 17.

DOI:10.1111/php.12015

PMID:23136898

Abstract

Intracellular pH plays an important role in many cellular events, such as cell growth, endocytosis, cell adhesion and so on. Some pH fluorescent probes have been reported, but most of them are one-photon fluorescent probes, studies about two-photon fluorescent probes are very rare. In this work, the geometrical structure, electronic structure and one-photon properties of a series of two-photon pH fluorescent probes have been theoretically studied by using density functional theory (DFT) method. Their two-photon absorption (TPA) properties are calculated using the method of ZINDO/sum-over-states method. Two types of two-photon pH fluorescent probes have been investigated by theoretical methods. The mechanisms of the Photoinduced Charge Transfer (PCT) probes and the Photoinduced Electron Transfer (PET) probes are verified specifically. Some designed strategies of good two-photon pH fluorescent probes are suggested on the basis of the investigated results of two mechanisms. For the PCT probes, substituting a stronger electron-donating group for the terminal methoxyl group is an advisable choice to increase the TPA cross section. For the PET probes, the TPA cross sections increase upon protonation.

摘要

细胞内 pH 值在许多细胞事件中起着重要作用，例如细胞生长、内吞作用、细胞黏附等。已经报道了一些 pH 值荧光探针，但大多数是单光子荧光探针，关于双光子荧光探针的研究非常罕见。在这项工作中，我们通过使用密度泛函理论（DFT）方法，对一系列双光子 pH 值荧光探针的几何结构、电子结构和单光子性质进行了理论研究。我们使用 ZINDO/sum-over-states 方法计算了它们的双光子吸收（TPA）性质。我们通过理论方法研究了两种类型的双光子 pH 值荧光探针。具体验证了光诱导电荷转移（PCT）探针和光诱导电子转移（PET）探针的机制。基于两种机制的研究结果，提出了一些设计双光子 pH 值荧光探针的良好策略。对于 PCT 探针，用更强的供电子基团取代末端甲氧基是增加 TPA 截面的可行选择。对于 PET 探针，质子化会增加 TPA 截面。