智能微流控检测芯片的构建及其Pb2+检测性能

通过将具有Pb²⁺响应性的聚（N-异丙基丙烯酰胺-共聚-苯并-18冠-6丙烯酰胺）智能微凝胶与H型微通道相结合，构建了一种能便捷、灵敏、可视化检测水溶液中Pb²⁺浓度的新型智能Pb²⁺检测微流控芯片。该微流控检测芯片主要由软光刻技术构建，并结合紫外光照聚合在H型微通道中原位构建智能微凝胶。基于该微凝胶的Pb²⁺响应性体积相变和H型微通道中的流体流动，该微流控检测芯片能将Pb²⁺浓度信号有效转换为易于检测读取的、可视化的H型微通道中指示液覆盖的指示柱数目的变化信号。通过光学显微镜便捷观察测量指示液覆盖的指示柱数目的变化，实现了对水溶液中痕量Pb²⁺浓度的超灵敏定量检测。该微流控检测芯片为水环境中的痕量Pb²⁺浓度的便捷、灵敏、可视化检测提供了新策略。

Fabrication of smart microfluidic chip and its Pb2+-detection performance

This work reported on fabrication of a novel smart microfluidic chip based on integration of Pb²⁺-responsive poly(N-isopropylacrylamide-co-benzo-18-crown-6-acrylamide) microgel and H-shaped microchannel, for facile, sensitive and visual detection of Pb²⁺ in water. The microfluidic chip was constructed using soft lithography technique combined with in situ synthesis of the smart microgel via UV-polymerization within the H-shaped microchannel. Based on the Pb²⁺-responsive volume change of the smart microgel and the flow in the H-shaped microchannel, the microfluidic chip enabled efficient conversion of Pb²⁺ concentration changes into easily detectable and readable, visual signal of number changes of indicating pillars within the H-shaped microchannel. By using a microscope for observing and measuring the number change of the indicating pillars, sensitive and quantitative detection of Pb²⁺ concentration in water was achieved. The proposed microfluidic chip provided a new strategy for facile, sensitive and visual detection trace Pb²⁺ in water.