KCS

Microfluidic technology have recently emerged as an efficient tool for the study of various chemical or biological reactions. Recently, we reported that high-throughput chemical or biological reactions could be performed in a continuous flow microfluidic channel with an automatic manner. However, there is a “memory effect” problem in the continuous flow system. Samples in the continuous stream could be stacked in the wall of a microfluidic channel, and they may occur unwanted flow hindrance. To resolve this problem, we recently developed a novel gradient microdroplet system. In this system, the sample stacking problem can be solved since two-phase liquid/liquid segmented flow reduces the memory effect. A serial dilution of reagent can be achieved in a stepwise manner using microfluidic concentration gradient generators. Then, desired concentrations of a reagent were sequentially trapped by a small volume of droplets to prevent the sample stacking. We believe that this microdroplet system will be of significant utility in monitoring chemical and biological effects for various concentrations of a reagent.