MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science & Engineering , Zhejiang University , Hangzhou 310027 , China.
Department of Chemistry , Zhejiang Sci-Tech University , Hangzhou 310018 , China.
ACS Appl Mater Interfaces. 2018 Aug 1;10(30):25706-25716. doi: 10.1021/acsami.8b08497. Epub 2018 Jul 20.
Tetra(4-pyridyl)porphyrin (TPyP)-functionalized thermosensitive ionic microgels (TPyP5-MGs) were synthesized by a two-step quaternization method. The obtained TPyP5-MGs have a hydrodynamic radius of about 189 nm with uniform size distribution and exhibit thermosensitive character. The TPyP5-MG microgel suspensions can optically respond to trace Pb ions in aqueous solution with high sensitivity and selectivity over the interference of other 19 species of metal ions (Yb, Gd, Ce, La, Bi, Ba, Zn, Ni, Co, Mn, Cr, K, Na, Li, Al, Cu, Ag, Cd, and Fe) by using UV-visible spectroscopy. The sensitivity of TPyP5-MGs toward Pb can be further improved by increasing the solution temperature. The limit of detection for TPyP5-MG microgel suspensions in the detection of Pb in aqueous solution at 50 °C is about 25.2 nM, which can be further improved to be 5.9 nM by using the method of higher order derivative spectrophotometry and is much lower than the U. S. EPA standard for the safety limit of Pb ions in drinking water. It is further demonstrated that the TPyP5-MG microgel suspensions have a potential application in the detection of Pb in real world samples, which give consistent results with those obtained by elemental analysis.
四（4-吡啶基）卟啉（TPyP）功能化温敏离子微凝胶（TPyP5-MGs）通过两步季铵化法合成。得到的 TPyP5-MGs 的水动力半径约为 189nm，具有均匀的粒径分布，并表现出温敏特性。TPyP5-MG 微凝胶悬浮液可以通过紫外-可见光谱对水溶液中的痕量 Pb 离子进行光学响应，具有高灵敏度和选择性，不受其他 19 种金属离子（Yb、Gd、Ce、La、Bi、Ba、Zn、Ni、Co、Mn、Cr、K、Na、Li、Al、Cu、Ag、Cd 和 Fe）的干扰。通过增加溶液温度，可以进一步提高 TPyP5-MGs 对 Pb 的灵敏度。在 50°C 下，TPyP5-MG 微凝胶悬浮液检测水溶液中 Pb 的检测限约为 25.2nM，通过高次导数分光光度法进一步提高至 5.9nM，远低于美国环保署饮用水中 Pb 离子安全限量标准。进一步证明了 TPyP5-MG 微凝胶悬浮液在实际样品中 Pb 检测方面具有潜在的应用价值，其结果与元素分析所得结果一致。
