Hikal Walid M, Harmon H James
Department of Physics, Oklahoma State University, Stillwater, OK 74078, USA.
J Hazard Mater. 2008 Jun 15;154(1-3):826-31. doi: 10.1016/j.jhazmat.2007.10.098. Epub 2007 Nov 4.
The interaction of meso-tri(4-sulfonatophenyl)mono(4-carboxyphenyl) porphyrin (C1TPP) with 2,4,6-trinitrotoluene (TNT) has been explored by UV-vis and fluorescence spectroscopy. The influence of temperature on the interaction has also been studied. C1TPP binds to TNT at pH 7.0 at room temperature via 1.94 kcal/mole hydrogen bonds with absorbance loss at 412-413 nm and the appearance of a new peak at 422-424 nm. The hydrogen binding of TNT to C1TPP was confirmed by the dissolution of the complex upon the addition of urea. Increasing the temperature results in the appearance of a new absorbance peak at 540 nm and absorbance loss at 515 nm with activation energy of 29.7 kcal/mole in the range of the hydrophobic bond energy. This suggests the hydrophobic bonding of TNT with the pyrrole nitrogens in the porphyrin. Increasing the concentration of the TNT in the solution quenches the fluorescence of the porphyrin following the Stern-Volmer equation. The association constants calculated from absorbance and fluorescence are expectedly similar.
通过紫外可见光谱和荧光光谱研究了中-三（4-磺酸苯基）单（4-羧基苯基）卟啉（C1TPP）与2,4,6-三硝基甲苯（TNT）的相互作用。还研究了温度对该相互作用的影响。在室温及pH 7.0条件下，C1TPP通过1.94千卡/摩尔的氢键与TNT结合，在412 - 413纳米处吸光度降低，在422 - 424纳米处出现新峰。加入尿素后复合物溶解，证实了TNT与C1TPP之间的氢键结合。温度升高导致在540纳米处出现新的吸光度峰，在515纳米处吸光度降低，在疏水键能范围内活化能为29.7千卡/摩尔。这表明TNT与卟啉中的吡咯氮形成了疏水键。溶液中TNT浓度的增加按照斯特恩-沃尔默方程猝灭了卟啉的荧光。由吸光度和荧光计算得到的缔合常数预计相似。
