Method for magnetic separation featuring magnetic particles in a multi-phase system

摘要

Methods and devices are provided for separation of magnetic particles and/or magnetic-associated substances from non-magnetic associated substances and media. The methods are specifically applicable to biological separation, and utilize a phase phenomenon arising from mutual interactions between suspended magnetic particles and interactions with the suspension medium. The phenomenon is exploited to produce and maintain a distinct, structured phase of magnetic particles, or ferrophase, within a multi-phase liquid system. A ferrophase is established within a separation chamber prior to introducing therein a test sample containing the target substances to be separated. The formation of a ferrophase is used to transport target substances from regions of relatively low magnetic field gradient to regions of relatively high magnetic field gradient within a high-gradient magnetic separation apparatus. Such transport of the ferrophase is accomplished at greater speed than the transport of individual magnetic particles within a single liquid phase, thereby enabling a more effective separation of magnetic from non-magnetic components.