Droplet evaporation-induced analyte concentration toward sensitive biosensing

Droplet evaporation is a natural phenomenon and a topic of wide concern in various research fields. Droplet-based biosensors have attracted much attention due to their promising application in clinical detection and environmental monitoring. The evaporation of analyte droplets often affects the concentration of analytes and the homogeneity of detection spots, which then influences the performance and the reliability of biosensors. Therefore, a deep understanding of droplet evaporation will be beneficial for improving the performance of droplet-based biosensors. This review mainly focuses on the droplet evaporation towards sensitive biosensing, including a fundamental understanding of wettability, modes of droplet evaporation, deposited patterns of droplets, and droplet evaporation on surfaces with different wettability. The emerging applications of droplet-based biosensors are also summarized, and the perspectives and challenges of droplet-based biosensing platforms are proposed.