MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science & Engineering, Zhejiang University, Hangzhou 310027, China.
Department of Chemistry, Zhejiang University, Hangzhou 310027, China.
Sensors (Basel). 2019 Sep 28;19(19):4223. doi: 10.3390/s19194223.
A highly selective and sensitive optical sensor was developed to colorimetric detect trace Fe ions in aqueous solution. The sensor was the sulfasalazine (SSZ) functionalized microgels (SSZ-MGs), which were fabricated via in-situ quaternization reaction. The obtained SSZ-MGs had hydrodynamic radius of about 259 ± 24 nm with uniform size distribution at 25 °C. The SSZ-MG aqueous suspensions can selectively and sensitively response to Fe ions in aqueous solution at 25 °C and pH of 5.6, which can be quantified by UV-visible spectroscopy and also easily distinguished by the naked eye. Job's plot indicated that the molar binding ratio of SSZ moiety in SSZ-MGs to Fe was close to 1:1 with an apparent association constant of 1.72 × 10 M. A linear range of 0-12 μM with the detection limit of 0.110 μM (0.006 mg/L) was found. The obtained detection limit was much lower than the maximum allowance level of Fe ions in drinking water (0.3 mg/L) regulated by the Environmental Protection Agency (EPA) of the United States. The existence of 19 other species of metal ions, namely, Ag, Li, Na, K, Ca, Ba, Cu, Ni, Mn, Pb, Zn, Cd, Co, Cr, Yb, La, Gd, Ce, and Bi, did not interfere with the detection of Fe ions.
一种高选择性和高灵敏度的光学传感器被开发出来，用于比色检测水溶液中的痕量 Fe 离子。该传感器是由柳氮磺胺吡啶（SSZ）功能化微凝胶（SSZ-MGs）组成的，它是通过原位季铵化反应制备的。所得 SSZ-MGs 的水动力半径约为 259±24nm，在 25°C 时具有均匀的粒径分布。SSZ-MG 水悬浮液可以在 25°C 和 pH 值为 5.6 的条件下选择性和灵敏地响应水溶液中的 Fe 离子，可以通过紫外-可见光谱定量，也可以通过肉眼轻松区分。Job 图表明，SSZ-MGs 中 SSZ 部分与 Fe 的摩尔结合比接近 1:1，表观结合常数为 1.72×10^M。发现线性范围为 0-12μM，检测限为 0.110μM（0.006mg/L）。所得检测限远低于美国环境保护署（EPA）规定的饮用水中 Fe 离子的最大允许水平（0.3mg/L）。19 种其他金属离子，即 Ag、Li、Na、K、Ca、Ba、Cu、Ni、Mn、Pb、Zn、Cd、Co、Cr、Yb、La、Gd、Ce 和 Bi 的存在并不干扰 Fe 离子的检测。
