Droplet Microarrays for Miniaturized and High-Throughput Experiments: Progress and Prospectives

Miniaturization in life sciences and chemical sciences offers substantial advantages to experimental workflows, such as increased throughput, reduced costs, and lower environmental impact. While microtiter plates are effective, further miniaturization is necessary to enhance efficiency and throughput. However, microtiter plates cannot be easily miniaturized to volumes below 5 µL, primarily because adhesive and capillary forces become stronger than the gravitational forces needed to confine the liquid within the wells. To overcome this, the droplet microarray (DMA) is developed, utilizing patterned adhesive regions on a liquid-repellent background to immobilize and confine sub-microliter droplets without physical barriers. This unique format enables novel applications such as droplet merging and parallel ultra-high-throughput manipulations. This review provides an overview of DMA's diverse applications and highlights the new experimental opportunities it offers, establishing it as a versatile tool for highly miniaturized, high-throughput biological and chemical experiments. The evolving requirements and future applications of the DMA approach are also discussed.