An OFF–ON chemosensor for biological and environmental applications: sensing Cd2+ in water using catanionic vesicles and in living cells
作者:Andrea Bencini、Francesco Caddeo、Claudia Caltagirone、Alessandra Garau、Mike B. Hurstouse、Francesco Isaia、Sandrina Lampis、Vito Lippolis、Francesco Lopez、Valeria Meli、Maura Monduzzi、Maria Cristina Mostallino、Sergio Murgia、Stefano Puccioni、Judith Schmidt、Pietro Paolo Secci、Yeshayahu Talmon
DOI:10.1039/c3ob41420e
日期:——
A new OFFâON fluorescent chemosensor (L1) for Cd2+ recognition based on a 5-chloro-8-hydroxyquinoline pendant arm derivative of 1,4,7-triazacyclononane ([9]aneN3) will be presented and its photochemical features in an MeCNâH2O 1â:â1 (v/v) mixture, in pure water, after inclusion within catanionic vesicles, and in living cells will be discussed. The coordination properties of L1 both in solution and in the solid state were preliminarily studied and its selectivity towards Cd2+versus a set of different metal ions (Cu2+, Zn2+, Cd2+, Pb2+, Al3+, Hg2+, Co2+, Ni2+, Mn2+, Mg2+, K+, Ca2+, Ag+, and Na+) was verified in MeCNâH2O 1â:â1 (v/v). In water, upon addition of increasing amounts of Cd2+ to L1 an enhancement of the fluorescence emission was detected. To overcome this serious drawback, L1 was dissolved in an innovative catanionic vesicular solution based on sodium bis(2-ethylhexyl) sulfosuccinate, a traditional surfactant, and 1-dodecyl-3-methylimidazolium bromide, an ionic liquid. When enclosed within the vesicle bilayers in water, L1 restored its fluorescence emission property upon addition of Cd2+. Remarkably, L1 enters the cellular membrane of living cells thus allowing the detection of intracellular Cd2+. These findings encourage the application of this new fluorescent chemosensor in real samples for histological and environmental analyses.
将介绍一种新的 OFF–ON 荧光化学传感器 (L1),该传感器用于识别 Cd²⁺,基于 1,4,7-三氮杂环诺烷([9]aneN₃)的 5-氯-8-羟基喹啉侧臂衍生物,并将讨论其在 MeCN–H₂O 1:1 (v/v) 混合物、纯水中、在阴离子胶束内包埋后以及在活细胞中的光化学特征。对 L1 在溶液中和固态下的配位性质进行了初步研究,并在 MeCN–H₂O 1:1 (v/v) 中验证了其对 Cd²⁺ 相较于一组不同金属离子(Cu²⁺、Zn²⁺、Cd²⁺、Pb²⁺、Al³⁺、Hg²⁺、Co²⁺、Ni²⁺、Mn²⁺、Mg²⁺、K⁺、Ca²⁺、Ag⁺ 和 Na⁺)的选择性。在水中,随着 Cd²⁺ 逐渐添加到 L1 中,检测到荧光发射增强。为了解决这一严重缺点,L1 被溶解在一种基于 sodium bis(2-ethylhexyl) sulfosuccinate(传统表面活性剂)和 1-dodecyl-3-methylimidazolium bromide(离子液体)的创新阴离子胶束溶液中。当 L1 被包裹在水中的胶束双层内时,添加 Cd²⁺ 后恢复了荧光发射特性。值得注意的是,L1 进入活细胞的细胞膜,从而允许检测细胞内的 Cd²⁺。这些发现鼓励在实际样本中应用这种新的荧光化学传感器进行组织学和环境分析。