衍生于双氰基二苯代乙烯的用于活体成像的双光子荧光锌离子探针

制备了衍生于双氰基二苯代乙烯的双光子荧光锌离子探针, 该探针以4-(2-吡啶甲基)哌嗪为锌离子受体, 当络合锌离子时, 探针的荧光强度增强了72.5倍和580 GM的双光子吸收截面. 该探针无细胞毒性且在体内环境中无pH敏感性, 其解离常数\begin{array}{c}{K}_d^{\mathit{TP}}\end{array}=(0.52±0.01) μmol/L. 性能测试结果表明, 该探针能选择性地检测活细胞中的游离锌离子, 耐时长达约1500 s, 且能探测活体组织80~150 μm深处的锌离子, 不受其它金属离子与生物膜的干扰.

Dicyanostilbene-derived Two-photon Fluorescence Probe for Free Zinc Ions in Live Cells and Living Tissues†

A novel two-photon fluorescence probe for Zn²⁺ derived from dicyanostilbene as a two-photon fluorophore and 4-(pyridine-2-ylmethyl)piperazine as a novel Zn²⁺ ligand was developed, and its structure was characterized by ¹H NMR, IR and elemental analysis. By UV-Vis absorption and absorption-titration experiments, one- and two-photon excited fluorescence experiments in femtosecond pulses, as well as cell-imaging and tissue-imaging experiments, the probe showed a 72.5-fold fluorescence enhancement in response to Zn²⁺, a large two-photon action cross-section(580 GM), a noncytotoxic effect, and pH insensitivity in the biolo-gically relevant range, with a dissociation constant(\begin{array}{c}{K}_d^{\mathit{TP}}\end{array}) of (0.52±0.01) μmol/L. The probe could detect free Zn²⁺ ions selectively in live cells for about 1500 s and in living tissues at a depth of 80—150 μm without interference from other metal ions or membrane-bound probes.