Acta Chimica Sinica ›› 2024, Vol. 82 ›› Issue (1): 9-15.DOI: 10.6023/A23100443 Previous Articles     Next Articles

Article

智能二维光子晶体水凝胶精准检测Hg2+

史雨晴, 储名珠, 韩波, 马豪杰, 李然, 侯雪艳, 张玉琦*(), 王记江   

  1. 延安大学化学与化工学院 陕西省化学反应工程重点实验室 延安市新能源新功能材料重点实验室 陕西 延安 716000
  • 投稿日期:2023-10-09 发布日期:2023-12-08
  • 基金资助:
    项目受国家自然科学基金(21663032); 项目受国家自然科学基金(22061041); 陕西省科技资源开放共享平台项目(2021PT-004)

Smart Two-dimensional Photonic Crystal Hydrogel for Accurate Detection of Hg2+

Yuqing Shi, Mingzhu Chu, Bo Han, Haojie Ma, Ran Li, Xueyan Hou, Yuqi Zhang(), Ji-Jiang Wang   

  1. Key Laboratory of New Energy & New Functional Materials, Shaanxi Key Laboratory of Chemical Reaction Engineering, College of Chemistry and Chemical Engineering, Yan’an University, Yan’an, Shaanxi 716000, China
  • Received:2023-10-09 Published:2023-12-08
  • Contact: E-mail: yqzhang@yau.edu.cn
  • Supported by:
    National Natural Science Foundation of China(21663032); National Natural Science Foundation of China(22061041); Open Sharing Platform for Scientific and Technological Resources of Shaanxi Province(2021PT-004)

A smart two-dimensional photonic crystal (2DPC) hydrogel was developed for accurate detection of Hg2+ by combining the Debye diffraction effect of 2DPC and the volume phase transition characteristic of hydrogel. The polystyrene (PS) 2DPC arrays were first fabricated by needle-tip-flow method, in which the monodispersed PS microspheres were orderly self-assembled on the water surface to form PS 2DPC and then transferred to glass slide. The poly(acrylamide-allylthiourea) hydrogels embedded with the PS 2DPC arrays were fabricated by “sandwich” method, in which the polymerization precursor solution including monomers acrylamide and allylthiourea was added to the PS 2DPC surface and covered with a glass slide, followed by photopolymerization. The atoms including N, O and S from functional groups on the hydrogel chains selectively coordinated with Hg2+, shortening the distance between the hydrogel chains and increasing the crosslinking density of the hydrogel. As a result, the hydrogel shrank and the PS microsphere spacing of the 2DPC decreased, which increased the diameter of the Debye diffraction ring. The microsphere spacing changes were acquired by monitoring Debye diffraction ring diameters before and after the response of the 2DPC hydrogel, achieving the highly sensitive, selective, reversible and fast detection of Hg2+. The linear detection ranges were in 10~100 nmol/L and 25~200 μmol/L, and the limit of detection was found to be 3.32 nmol/L. The prepared smart 2DPC hydrogel was used to detect Hg2+ in cosmetics and water samples to evaluate its practicability. The recovery for the detection of Hg2+ was 98.8%~102.6% and the relative standard deviation was 0.57%~1.09% for a commercially lipstick, and they were 97.2%~103.4% and 0.61%~0.99% for the tap water, respectively. The results demonstrated that our constructed smart 2DPC hydrogels have good applicability, accuracy and reliability for the detection of Hg2+ in real samples. The method is simple for testing, only requiring a laser pointer and a ruler, without needing sophisticated instruments, and it can realize portable detection, providing a new strategy for detecting metal ions.

Key words: two-dimensional photonic crystals, Debye diffraction effect, smart hydrogel, volume phase transition, mercury ions