Holophrase

在许多生物实验中，监测和调整溶液的pH值是很重要的，因为给定溶液的酸度水平决定或携带了正在进行的过程的信息。最常用的pH传感器是pH纸条和电导率探针，它们根据溶液的酸度给出简单的读数。这些方法非常便宜，不需要额外的仪器，但它们没有集成，需要大量的解决方案。在微流体中，最常见的方法是监测添加到细胞培养基中的染料的吸收变化，使实验要求和方案复杂化。存在许多其他集成解决方案，但它们通常都有自己的警告和限制。在这里，我们建议开发一种灵活的解决方案，用于实时，无标签，定量光学成像读出液体溶液的pH值。我们的方法结合了易于访问，简单性和笨重解决方案的成本，以及最复杂传感器的准确性和集成水平。我们的设备可以创建一个全息图像，随着溶液的pH值实时变化，而不需要引入吸收染料或昂贵而复杂的传感电路和繁琐的校准步骤。

In many biological experiments, it is important to monitor and adjust the pH level of a solution, since the level of acidity of a givensolution determines or carries information on the process at play. The most used pH sensors are pH paper strips and conductivityprobes, which give a simple readout that depends on the acidity of a solution. These methods are very cheap and do not needadditional instrumentation, but they are not integrated and require large volumes of the solution. In microfluidics, the most commonapproach monitors the change in absorption of a dye added to the cell culture medium complicating the experimental requirementsand protocols. Many other integrated solutions exist but often they come with their own caveats and limitations. Here we propose todevelop a flexible solution for the real time, label free, quantitative optical imaging readout of the pH level of a liquid solution. Ourapproach brings together the ease of access, simplicity, and cost of bulkier solutions, with the accuracy and level of integration of themost sophisticated sensors. Our device creates a holographic image that changes in real time with the pH of the solution, withoutrequiring the introduction of absorbing dyes or costly and complicated sensing circuitry and cumbersome calibration steps.