Systems and methods for three-dimensional extraction of target particles ferrofluids

Abstract

Systems, methods and devices are presented for extracting target particles within a ferrofluid medium. In some embodiments, a fluidic channel receives a flow of a mix of one or more types of target particles, where at least one magnetic field source is configured to react with the flow such that a force (indirect or direct) is placed on the particles of the mix, across the width and/or the height of the fluidic channel. An extraction opening placed on one wall is provided and configured to extract at least one type of target particle.

1 . A method for extracting particles within a ferrofluid medium, the method comprising:
 flowing a mix comprising a ferrofluid medium containing one or more types of target particles through at least one microfluidic channel, the at least one channel having:
 a first inlet portion for receiving the flow and a second portion spaced downstream from the first portion, 
 a first side spaced away from a second side and comprising to a width of the channel, and 
 a third side spaced away from a fourth side and comprising a height of the channel, 
 wherein the mix flows through the channel in a first direction from the first portion to the second portion; 
   applying a magnetic field adjacent at least one of the sides of the channel, the magnetic field configured to concentrate at least one type of target particle contained in the mix within a width region, the width region comprising a portion of the width, and a height region, the height region comprising a portion of the height located at or adjacent to the third side, such that the at least one first type of target particles from the flow are concentrated within the width region and the height region, creating a concentrated flow of target particles of the at least one first type; and   extracting the concentrated flow of target particles via an extraction opening arranged on the third side at or near the second portion, wherein the concentrated flow of target particles from the extraction opening includes an exit velocity.   
     
     
         2 . The method of  claim 1 , wherein concentrating comprises at least one of separating, focusing and concentrating. 
     
     
         3 . The method of  claim 1 , wherein a type of particles corresponds to at least one of a size, shape, mass, and charge of one or more particles. 
     
     
         4 . The method of  claim 1 , wherein the first type of target particles comprises at least one of target moieties and target biological cells. 
     
     
         5 . The method of  claim 1 , wherein applying a magnetic field includes at least one of current-carrying electrodes and magnets. 
     
     
         6 . The method of  claim 1 , further comprising adjusting the exit velocity of the concentrated flow of target particles by at least one of:
 configuring the magnetic field to effect forces on the flow affecting the exit velocity,   configuring the size of the extraction opening to increase velocity,   controlling the flow resistance from the extraction opening, and   providing at least one of a pressure sink and a flow sink arranged downstream of the extraction opening.   
     
     
         7 . A system for extracting particles within a ferrofluid medium, the system comprising:
 at least one microfluidic channel having
 a first inlet portion and a second portion spaced downstream from the first portion for receiving a flow of a mix comprising a ferrofluid medium containing one or more types of target particles, 
 a first side spaced away from a second side and comprising a width of the fluidic channel, and 
 a third side spaced away from a fourth side and comprising a height of the fluidic channel, 
 wherein fluid flows through the fluidic channel in a first direction from the first end to the second end; 
   magnetic field means arranged adjacent at least one of the sides of the fluidic channel, the magnetic field configured to focus at least one type of target particles contained in the ferrofluid medium flow within a width region, the width region comprising a portion of the width, and a height region, the height region comprising a portion of the height located at or adjacent to the third side, such that the target particles from the flow are concentrated within the width region and the height region creating a concentrated flow of particles; and   an extraction opening arranged on the third side at or near the second end, the extraction opening configured to receive and direct the concentrated flow of target particles from the fluidic channel at an exit velocity.   
     
     
         8 . The system of  claim 7 , wherein the target particles comprise at least one of target moieties and target biological cells. 
     
     
         9 . The system of  claim 7 , wherein the magnetic field means comprises at least one of: one or more current-carrying electrodes and one or more magnets. 
     
     
         10 . The system of  claim 7 , further comprising velocity adjustment means. 
     
     
         11 . The system of  claim 10 , wherein the velocity adjustment means comprises flow resistance means. 
     
     
         12 . The system of  claim 10 , wherein the velocity adjustment means comprises at least one of
 adjusting the magnetic field to effect forces on the flow affecting the exit velocity,   the size of the extraction opening is configured to increase velocity,   controlling the flow resistance from the extraction opening, and   providing at least one of a pressure sink and a flow sink arranged downstream of the extraction opening.