Droplet merging on a lab-on-a-chip platform by uniform magnetic fields

• Main Authors: Varma, Vijaykumar Babulalji, Ray, Ayan, Wang, Zhao Meng, Wang, Zhi Ping, Ramanujan, Raju Vijayaraghavan
• Other Authors: School of Materials Science & Engineering
• Format: Article
• Language: English
• Published: 2018
• Subjects: DRNTU::Engineering::Materials; Magnetic Properties and Materials; Droplet-based Microfluidic
• Online Access: https://hdl.handle.net/10356/80800; http://hdl.handle.net/10220/46605
• Institution: Nanyang Technological University

Droplet microfluidics offers a range of Lab-on-a-chip (LoC) applications. However, wireless and programmable manipulation of such droplets is a challenge. We address this challenge by experimental and modelling studies of uniform magnetic field induced merging of ferrofluid based droplets. Control of droplet velocity and merging was achieved through uniform magnetic field and flow rate ratio. Conditions for droplet merging with respect to droplet velocity were studied. Merging and mixing of colour dye + magnetite composite droplets was demonstrated. Our experimental and numerical results are in good agreement. These studies are useful for wireless and programmable droplet merging as well as mixing relevant to biosensing, bioassay, microfluidic-based synthesis, reaction kinetics, and magnetochemistry.