Micro-fluidic device for sorting particles, and methods for sorting particles
A method and device for the sorting and focusing of suspended particles is disclosed. The device has a micro-fluidic channel, at least one inlet and a number of outlets for providing, sorting and receiving particles. A patterned array of grooves is present inside the micro-fluidic channel. The inlets and outlets are connected to the micro-fluidic channel. The particles are sorted by the array of grooves. The method consists of providing particles in a flow-focused manner to one end of the micro-fluidic channel using at least one inlet. The particles are sorted by the array of grooves present in the micro-fluidic channel. Particles are collected by a number of outlets which are connected to the other end of the micro-fluidic channel.
1. A micro-fluidic device for sorting particles in a liquid sample, the device comprising
a micro-fluidic channel comprising a particle separation region comprising an array of grooves, the grooves being oriented at an angle in the range of 20 degrees to 70 degrees with respect to a main axis of the channel;
a means for injecting the liquid sample into said micro-fluidic channel;
a means for collecting particles whereby the means for injecting the liquid sample and the means for collecting particles are interconnected via the micro-fluidic channel; and
the liquid sample comprising the particles to be sorted, the liquid sample being disposed within the micro-fluidic channel,
wherein the dimensions of the micro-fluidic channel are considerably larger than the dimensions of the grooves to prevent confinement effects, the height of the micro-fluidic channel being at least five times the depth of the grooves, the micro-fluidic channel being configured to avoid recirculation effects inside the micro-fluidic channel, and
wherein the width and spacing between the grooves is at least 2 times the size of the particles to be sorted.
2. A micro-fluidic device according to claim 1 , wherein the array of grooves is partly patterned at the bottom surface of the micro-fluidic channel such that the bottom surface of the micro-fluidic channel comprises a non-patterned part, and wherein the non-patterned part of the bottom surface is configured to flow-focus the stream of particles.
3. A micro-fluidic device according to claim 1 , wherein the height of the micro-fluidic channel is at least 10 times the depth of the grooves.
4. A micro-fluidic device according to claim 1 , wherein said grooves are open-ended.
5. A micro-fluidic device according to claim 1 , wherein the width of the channel is at least 50 times the width of the grooves.
6. A micro-fluidic device according to claim 1 , wherein the depth of each groove of the array of grooves is at least the size of the particles to be sorted.
7. A micro-fluidic device according to claim 1 , wherein the width and spacing between the grooves is at least 10 times the size of the particles to be sorted.
8. A micro-fluidic device according to claim 1 , wherein the array of grooves are slanted and patterned at the bottom of the surface of the micro-fluidic channel.
9. A micro-fluidic device according to claim 1 , wherein the means for injecting the liquid sample into to the micro-fluidic channel does so in a flow-focused manner.
10. A micro-fluidic device according to claim 1 , wherein the means for injecting the liquid sample comprises at least one inlet.
11. A micro-fluidic device according to claim 1 , wherein the means for injecting the liquid sample comprises an inlet and one or more micro-fluidic channels.
12. A micro-fluidic device according to claim 1 , wherein the means for collecting particles are one or more micro-fluidic channels, the channels being arranged to prevent recombining the segregated streams.
13. A micro-fluidic device according to claim 12 , wherein the channels are evenly spaced, thereby ensuring that they have the same hydrodynamic resistance.
14. A micro-fluidic device according to claim 1 , further comprising a sedimentation region arranged to let particles partly sediment in order to diminish recirculation effects on the particles present above the array of grooves.
15. A method for sorting particles in a liquid sample with a device according to claim 1 , the method comprising injecting the liquid sample into the micro-fluidic channel such that the liquid sample comprising the particles to be sorted is disposed within the micro-fluidic channel, separating the particles with the separation region and capturing streams of different particles with the means for collecting particles.
16. A method according to claim 15 , wherein injecting the liquid sample into the micro-channel is performed in a flow focused manner.
17. A method according to claim 15 , further comprising allowing the sedimentation of the particles in said liquid sample before injecting the liquid sample into the micro-fluidic channel.
18. A method according to claim 15 , the method further comprising adjusting focusing and sample injection flow of one or more micro-fluidic channels for focusing the flow of particles.
19. A method for sorting particles in a liquid sample with a device according to claim 1 , comprising flowing the liquid sample comprising the particles to be sorted in the micro-fluidic channel at an average velocity which is comparable to the sedimentation velocity of said particles.
20. A method for sorting particles in a liquid sample with a device according to claim 1 , comprising flowing the liquid sample comprising the particles to be sorted in the micro-fluidic channel at an average velocity which is substantially larger than the sedimentation velocity of said particles.
21. A micro-fluidic device according to claim 1 , wherein the width and spacing between the grooves is at least 5 times the size of particles to be sorted.
22. A micro-fluidic device according to claim 1 , wherein the array of grooves is fully-patterned at the bottom surface of the micro-fluidic channel.
23. A micro-fluidic device according to claim 1 , wherein
the width and spacing between the grooves is at least 5 times the size of particles to be sorted; and
the depth of each groove of the array of grooves is at least the size of the particles to be sorted.
24. A method for sorting particles in a liquid sample with a device according to claim 23 , the method comprising injecting the liquid sample comprising the particles to be sorted into the micro-fluidic channel, separating the particles with the separation region and capturing streams of different particles with the means for collecting particles.