Analysis of separators for magnetic beads recovery: From large systems to multifunctional microdevices

The use of functionalized magnetic beads has significantly improved the selective separation of compounds from complex fluid solutions compared to conventional technologies. As a result, the capture of non-magnetic compounds through magnetic methods has gained much attention in recent years with current research expanding the concept of magnetic separation to different fields. Nevertheless, the magnetic separation step remains one of the most important stages of these processes and should be carefully analyzed in order to facilitate the successful design of magnetic beads applications. In this work, the fundamental principles of magnetic separations are reviewed in order to establish the underlying theoretical background and to further facilitate the development of efficient magnetic separators. Different alternatives for large scale processes are presented, such as High Gradient Magnetic Separation (HGMS) columns and Open Gradient Magnetic Separation (OGMS) systems, along with their main advantages and practical limitations. Finally, the integration of continuous microfluidic magnetic separators is introduced as a promising alternative for small scale applications due to their multifunctional features. (C) 2016 Elsevier B.V. All rights reserved.