Franke M, Leubner S, Dubavik A, George A, Savchenko T, Pini C, Frank P, Melnikau D, Rakovich Y, Gaponik N, Eychmüller A, Richter A
Institute of Semiconductors and Microsystems, Faculty of Electrical and Computer Engineering, Technische Universität Dresden, 01062, Dresden, Germany.
Center for Advancing Electronics Dresden (cfaed), Technische Universität Dresden, 01062, Dresden, Germany.
Nanoscale Res Lett. 2017 Dec;12(1):314. doi: 10.1186/s11671-017-2069-x. Epub 2017 Apr 27.
Microfluidic devices present the basis of modern life sciences and chemical information processing. To control the flow and to allow optical readout, a reliable sensor material that can be easily utilized for microfluidic systems is in demand. Here, we present a new optical readout system for pH sensing based on pH sensitive, photoluminescent glutathione capped cadmium telluride quantum dots that are covalently immobilized in a poly(acrylate) hydrogel. For an applicable pH sensing the generated hybrid material is integrated in a microfluidic sensor chip setup. The hybrid material not only allows in situ readout, but also possesses valve properties due to the swelling behavior of the poly(acrylate) hydrogel. In this work, the swelling property of the hybrid material is utilized in a microfluidic valve seat, where a valve opening process is demonstrated by a fluid flow change and in situ monitored by photoluminescence quenching. This discrete photoluminescence detection (ON/OFF) of the fluid flow change (OFF/ON) enables upcoming chemical information processing.
微流控设备是现代生命科学和化学信息处理的基础。为了控制流体流动并实现光学读出，需要一种可靠且易于用于微流控系统的传感材料。在此，我们展示了一种基于对pH敏感的、光致发光的谷胱甘肽包覆碲化镉量子点的新型pH传感光学读出系统，这些量子点通过共价键固定在聚丙烯酸水凝胶中。为了实现适用的pH传感，将生成的杂化材料集成到微流控传感器芯片装置中。该杂化材料不仅允许原位读出，还由于聚丙烯酸水凝胶的溶胀行为而具有阀门特性。在这项工作中，杂化材料的溶胀特性被应用于微流控阀座，通过流体流动变化演示了阀门开启过程，并通过光致发光猝灭进行原位监测。流体流动变化（关/开）的这种离散光致发光检测（开/关）能够实现未来的化学信息处理。
