Automatic magnetic manipulation of droplets on an open surface using a superhydrophobic electromagnet needle

作者：Yang, Chao; Ning, Yongfeng; Ku, Xiaoyong; Zhuang, Guisheng; Li, Gang^*

来源：Sensors and Actuators B: Chemical , 2018, 257: 409-418.

DOI：10.1016/j.snb.2017.10.118

• Droplet manipulation
• Electromagnet needle
• Magnetic beads
• Open surface
• Superhydrophobic coating

In this paper, we present a novel magnetic droplet manipulation platform that exploits a superhydrophobic electromagnet needle (EMN) to perform complex liquid manipulations on an open surface. By switching or adjusting the EMN power supply, the platform can simply and flexibly perform a full range of droplet manipulations, including droplet transport, fusion, mixing, magnetic beads (MBs) extraction, and droplet dispensing. Owing to its superhydrophobic coating, the EMN can directly contact a magnetic droplet and then exert a strong magnetic force on the paramagnetic beads suspended in it for effective droplet manipulation without the wetting or contamination problems. This offers particular advantages to multi-step biochemical assays. We also investigated the effects of the MBs concentrations, droplet volume, hydrophilic pattern size and current amplitude applied to the EMN on the droplet kinematics. The EMN-based droplet manipulation is facile, cost-effective, and programmable, and will significantly enhance the functionality of magnetic droplet platforms, and thus broaden their applicability to numerous fields of life science.

• 出版日期2018-3
• 单位重庆大学