Moura Nuno M M, Nuñez Cristina, Santos Sérgio M, Faustino M Amparo F, Cavaleiro José A S, Neves M Graça P M S, Capelo José Luis, Lodeiro Carlos
Department of Chemistry and QOPNA, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal, Fax: (+351) 234-370-084.
BIOSCOPE Group, REQUIMTE, Chemistry Department, Faculty of Science and Technology, University NOVA of Lisbon, 2829-516, Monte da Caparica, Portugal, Fax: (+351) 212-948-550.
Chempluschem. 2013 Oct;78(10):1230-1243. doi: 10.1002/cplu.201300216. Epub 2013 Aug 19.
The sensing ability of benzoporphyrins 1-5 and porphyrin-2-ylpyridines 6-10 towards different metal ions Na , K , Ca , Mg , Pb , Cu , Ni , Zn , Cd , Hg , and Cr was explored in solution by absorption and fluorescence spectroscopy. Strong changes in the ground and excited state were detected only in the case of the soft metal ions Zn , Cd , Hg , and Cu . A one metal per ligand molar ratio was obtained in all cases for compounds 1-5. In addition, a remarkable increase of the emission intensity for 1-5 was observed in the presence of Hg . In this series the highest association constant was obtained for compound 1 (log K =(8.71±4.81)×10 ), which was able to quantify 32 ppb of Hg . For compounds 6-10 containing an additional pyridine unit, a metal-to-ligand stoichiometry of 1:2 was determined. The gas-phase detection abilities of compounds 1-10 using MALDI-TOF-MS spectrometry confirmed that their sensorial ability and theoretical calculations are in accordance with the stoichiometry observed. Our preliminary studies show that some of the compounds supported in polymethylmethacrylate (PMMA) films can be used as promising metal-ion solid chemosensors; it was found that compound 1 in PMMA is able to distinguish between Zn and Hg in the solid phase.
通过吸收光谱和荧光光谱在溶液中探究了苯并卟啉1 - 5和卟啉 - 2 - 基吡啶6 - 10对不同金属离子Na⁺、K⁺、Ca²⁺、Mg²⁺、Pb²⁺、Cu²⁺、Ni²⁺、Zn²⁺、Cd²⁺、Hg²⁺和Cr³⁺的传感能力。仅在软金属离子Zn²⁺、Cd²⁺、Hg²⁺和Cu²⁺的情况下检测到基态和激发态的强烈变化。对于化合物1 - 5，在所有情况下均获得了每个配体一个金属的摩尔比。此外，在Hg²⁺存在下观察到1 - 5的发射强度显著增加。在该系列中，化合物1获得了最高的缔合常数（log K =(8.71±4.81)×10⁴），它能够定量32 ppb的Hg²⁺。对于含有额外吡啶单元的化合物6 - 10，确定了金属与配体的化学计量比为1:2。使用基质辅助激光解吸电离飞行时间质谱（MALDI - TOF - MS）光谱对化合物1 - 10进行气相检测的能力证实，它们的传感能力和理论计算与观察到的化学计量相符。我们的初步研究表明，聚甲基丙烯酸甲酯（PMMA）薄膜负载的一些化合物可作为有前景的金属离子固体化学传感器；发现PMMA中的化合物1能够在固相中区分Zn²⁺和Hg²⁺。
