Nano-Science Center & Department of Chemistry, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen Ø, Denmark.
Nano-Science Center & Department of Chemistry, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark.
ACS Sens. 2022 May 27;7(5):1506-1513. doi: 10.1021/acssensors.2c00242. Epub 2022 May 10.
As part of moving our optical pH and dissolved oxygen (DO) optical chemosensors toward industrial applications, we decided to explore a many-sensors-in-one principle. It was tested if physical segregation of the optical sensor components in a single sensor polymer could remove cross-talk and quenching. It was found that a design concept with an oxygen-responsive dye in polymer nanoparticles and a pH-responsive dye in an organically modified siloxane polymer resulted in a robust pH/O dual optical sensor. Individually, the O-sensitive nanoparticles, a known component for optical DO sensing, and the pH sensor are operational. Thus, it was decided to test if nanoparticles enclosed within the pH-sensitive responsive sol-gel (i) could work together if segregated and (ii) could operate with a single intensity signal that is without a reference signal; developments within industrial optical sensor technology indicate that this should be feasible. The prototype optode produced in this work was shown to have a negligible drift over 60 h, bulk diffusion-limited DO response, and independent response to pH and O. On the individual optode, pH calibration was found to show the expected sigmoidal shape and p, while the complexity of the calibration function for the DO signal was significant. While the engineering of the sensor device, optics, and hardware are not robust enough to attempt generic sensor calibration, it was decided to demonstrate the design concept in simple fermentation experiments. We conclude that the dual sensor design with the physical segregation of components is viable.
为了将我们的光学 pH 值和溶解氧（DO）光学化学传感器推向工业应用，我们决定探索一种多传感器合一的原理。我们测试了在单个传感器聚合物中物理隔离光学传感器组件是否可以消除串扰和猝灭。结果发现，一种设计概念，即将氧响应染料置于聚合物纳米粒子中，将 pH 响应染料置于有机改性硅氧烷聚合物中，可产生稳健的 pH/O 双光学传感器。单独使用时，O 敏感纳米粒子（一种用于光学 DO 传感的已知组件）和 pH 传感器均能正常工作。因此，我们决定测试纳米粒子是否可以在 pH 敏感响应溶胶-凝胶内工作，如果隔离，它们是否可以使用单一强度信号（无需参考信号）进行操作；工业光学传感器技术的发展表明这应该是可行的。本工作中制备的原型光纤传感器在 60 h 内漂移可忽略不计，具有体扩散限制的 DO 响应，以及对 pH 和 O 的独立响应。在单个光纤传感器上，发现 pH 校准呈现出预期的 S 形和 p，而 DO 信号校准函数的复杂性非常显著。尽管传感器设备的工程设计、光学和硬件还不够稳健，无法进行通用传感器校准，但我们决定在简单的发酵实验中展示设计概念。我们得出结论，采用组件物理隔离的双传感器设计是可行的。
