Various types of magnetic digital microfluidics. (a) Microstructure-assisted magnetic droplet manipulation. Reproduced Kanitthamniyom et al., Microsys. Nanoeng.
6, 48 (2020). Copyright 2020 Author(s), licensed under the Creative Common Attribution (CC BY) License. (b) Surface tension energy trap-assisted magnetic droplet manipulation. Reproduced with permission from Zhang et al., Lab Chip 13, 4827–4831 (2013). Copyright 2013 John Wiley and Sons. (c) Magnetic substrate for droplet manipulation. Reproduced with the permission from Seo et al., Polym. Adv. Technol. 24, 1075–1080 (2013). Copyright 2013 John Wiley and Sons.