A new magnetic bead-based, filterless bio-separator with planar electromagnet surfaces for integrated bio-detection systems

A new filterless bio-separator separating magnetic microbeads from a carrier fluid has been designed, fabricated, and characterized as a core component of biological cell sampling and detecting systems. To maximize the sampling capability, a planar electromagnet surface with a serpentine coil and semi-encapsulated permalloy has been realized. Using this bio-separator, antibody-coated magnetic beads have been successfully separated from the bio-buffer suspension solution and characterized in dynamic fluid flow. The magnetic characteristics of the bio-separator have been simulated and experimentally studied to establish and validate the design rules for fabrication. The realized filterless bio-separator has a high potential in biomedical and biological detection systems. It is especially useful in selective sampling and separation of small amounts of bio-molecules (e.g., antigen) for on-chip micro total analysis systems (mu-TAS) or remote detection systems. (C) 2000 Elsevier Science S.A. All rights reserved.