Abstract

How to Choose the Right Chemical Formulations for Microfluidic Applications?

Ségolène Antoine, Scientific Account Manager, Emulseo

Droplet-based microfluidics has emerged as an efficient solution for rapid, precise, quantitative and low-cost screening tool for biological and chemical applications. The monodisperse water-in-oil droplets generated in droplet-based microfluidic devices are loaded with biological or chemical agents. The droplets are used as microcompartments. To analyze and/or sort the content of the droplets, dyes are usually added. The droplets are then monitored and sorted according to their fluorescence signal. A common issue in droplet-based microfluidic experiments involving the use of dyes is dye leakage. The release of the dye into the oil phase and neighboring droplets results in a decrease of the accuracy of fluorescence monitoring. Some of the parameters influencing the retention of dyes in droplets are the nature of the buffer or cell culture medium, the choice of fluorophore and its hydrophilicity, the oil phase and the concentration, nature and molecular weight of the surfactant. In this presentation, we will first present a comprehensive investigation of the impact of oil choice and surfactant concentration on dye leakage during droplet-based microfluidic experiments. The performance of two fluorinated oils and surfactant concentrations on dye retention will be discussed. Secondly, the impact on the results resolution of the surfactant auto-fluorescence will be discussed.