Faculty of Engineering and the Environment, University of Southampton, Southampton, SO17 1BJ, UK.
Lab Chip. 2018 Jun 26;18(13):1903-1913. doi: 10.1039/c8lc00092a.
In droplet microfluidics, droplets have traditionally been considered discrete self-contained reaction chambers, however recent work has shown that dissolved solutes can transfer into the oil phase and migrate into neighbouring droplets under certain conditions. The majority of reports on such inter-droplet "crosstalk" have focused on surfactant-driven mechanisms, such as transport within micelles. While trialling a droplet-based system for quantifying nitrate in water, we encountered crosstalk driven by a very different mechanism: conversion of the analyte to a gaseous intermediate which subsequently diffused between droplets. Importantly we found that the crosstalk occurred predictably, could be experimentally quantified, and measurements rationally post-corrected. This showed that droplet microfluidic systems susceptible to crosstalk such as this can nonetheless be used for quantitative analysis.
在液滴微流控中，液滴传统上被认为是离散的自成一体的反应室，然而最近的研究表明，在某些条件下，溶解的溶质可以转移到油相并迁移到相邻的液滴中。大多数关于这种液滴间“串扰”的报告都集中在表面活性剂驱动的机制上，例如胶束内的传输。在尝试基于液滴的系统来定量水中的硝酸盐时，我们遇到了一种由非常不同的机制驱动的串扰：分析物转化为气态中间体，随后在液滴之间扩散。重要的是，我们发现串扰是可预测的，可以通过实验定量，并进行合理的后校正。这表明，尽管如此，像这样容易受到串扰影响的液滴微流控系统仍然可以用于定量分析。
