A magnetic device for processing biological objects including a soft magnetic center pole having a bottom end and a tapered tip end; first and second soft magnetic side poles disposed on opposite sides of the soft magnetic center pole and respectively having first and second bottom ends, the first and second soft magnetic side poles respectively having first and second top ends that bend inward toward the soft magnetic center pole with a first outward side of the first top end and a second outward side of the second top end being substantially coplanar; a magnetic flux source generating magnetic flux in the soft magnetic center pole and the first and second soft magnetic side poles; and a channel plate having a channel embedded therein and a first planar surface that is operable to be in contact with or in close proximity to the first and second outward sides.

A magnetic separation device has a membrane having a plurality of pores, a magnetically soft material layer disposed on the membrane, and a passivation layer disposed on the magnetically soft material layer. The magnetic separation device may be part of a microfluidic device having a lateral flow channel and a vertical flow magnetic separation filter. The magnetic separation device may be used to separate magnetically tagged particles, such as cells.

A self-cleaning magnetic filter for removing ferrous contaminates from a natural gas process stream including a housing through which the process stream follows for removing ferrous contaminates in the process stream by magnetic attraction with a plurality of magnetic bars that are removably disposed in a plurality of non-magnetic sleeves disposed within the housing. A recirculating washing solution is used to flush contaminates that adhere to the exterior surfaces of the non-magnetic sleeves and from the housing. A bag filter is used to remove contaminates from the washing solution to allow recycling the washing solution.

The invention is directed to a method and a system for producing a ferrofluid comprising providing a stock solution with Fe(II) and Fe(III); mixing the stock solution with a base to form magnetic nanoparticles and a spent solution, said method further comprising a separation step of separating the nanoparticles from the spent solution by applying a magnet to immobilize the nanoparticles and remove at least part of the spent solution as supernatant from the immobilized nanoparticles. In another aspect, the invention is directed to the resulting ferrofluid.

Disclosed are methods for identifying desired members from a display libraries, including bacteriophage display libraries. Display library members can be amplified in the presence of a target compound so that cycles of selection can be rapidly completed.

A method of operating a magnetic selector is provided. The magnetic selector includes a housing including a floor having a floor surface, a magnet carrier disposed on an opposite side of the floor from the floor surface and having at least one magnet disposed thereon, the magnet carrier being moveable relative to the floor between a first state wherein the magnet carrier is adjacent the floor and a second state wherein the magnet carrier is spaced from the floor. The method includes disposing a container on the floor surface, moving the magnet carrier to the first state to apply a magnetic field to a fluid in the container, moving the magnet carrier to the second state from the first state to disengage the magnetic field from the container, and removing the container.

A magnetic selector includes a housing configured to receive a container and having a floor upon which the container is disposed. The selector also includes a magnet carrier disposed on an opposite side of the floor from the container. The magnet carrier has at least one magnet disposed thereon and being moveable relative to the floor between a first state wherein the magnet carrier is adjacent the floor and a second state wherein the magnet carrier is spaced from the floor. The selector may include a door. The magnetic selector is usable in a fluid processing system that includes a fluid processor connectable to a source container filled with a biological fluid. A container is disposed in the magnetic selector and connected to the processor along a fluid pathway. The processor is configured to separate the biological fluid from the source container into at least two streams of material.

A magnetic bead separation method includes: storing, in a container, a mixed liquid containing a magnetic bead and a liquid containing target molecules, and adsorbing the target molecules on the magnetic bead, the magnetic bead containing a Fe-based metal soft magnetic particle and a coating film with which the Fe-based metal soft magnetic particle is coated, and having a saturation magnetization of 50 emu/g or more and 250 emu/g or less; applying an external magnetic field to the container and magnetically attracting at least a part of the magnetic bead by the external magnetic field; and applying an acceleration to the container while the magnetic bead is magnetically attracted by the external magnetic field and desorbing the liquid adhering to the magnetic bead.

There is provided a method of extracting material from a fluid method of extracting material from a fluid, the fluid being held within a fluid chamber. The method comprises drawing, with a magnetic field generating system, at least one magnetically susceptible member through the fluid around a closed path between at least three points in the chamber, said at least one member being adapted to bind to material in fluid in the chamber. The at least three points are arranged relative to each other in a shape having at least two dimensions, the magnetic field generating system being configured to move the at least on magnetically susceptible member directly between the at least three points, material in the fluid binding to the at least one magnetically susceptible member when it comes into contact with the at least one member as it moves through the fluid.

Methods are provided for separating magnetically responsive beads from a droplet in a droplet actuator. Droplet operations electrodes and a magnet are arranged in a droplet actuator to manipulate a bead-containing droplet and position it relative to a magnetic field region that attracts the magnetically responsive beads. The droplet operations electrodes are operated to control the droplet shape and transport it away from the magnetic field region to form a concentration of beads in the droplet. The continued transport of the droplet away from the magnetic field causes the concentration of beads to break away from the droplet to yield a small, concentrated bead-containing droplet immobilized by the magnet.