Microfluidics device for fabrication of large, uniform, injectable hydrogel microparticles for cell encapsulation

Abstract

The devices, methods, and compositions disclosed herein accomplish robust cell encapsulation in polymer microparticles using a vertically oriented microfluidic device. A hydrophilic polymer precursor solution is flowed into a first inlet channel, which extends inward from an upper surface of the device housing. A hydrophobic fluid is flowed into a second inlet channel, which extends inward from a lower surface of the device housing. The two inlet channels meet at a junction, and an outlet channel extends away from the two inlet channels. When the two inwardly flowing streams meet at the junction, the polymer precursor solution disperses into the hydrophobic fluid. The dispersed precursor droplets are photopolymerized into microparticles as they travel through the outlet channel. The resulting microparticles are highly uniform, and are larger than conventionally formed microparticles. Cells of varying types can be encapsulated with high viability and spatial uniformity.

1 - 23 . (canceled) 
     
     
         24 . A composition comprising:
 a plurality of microparticles comprising an average diameter of from 100 micrometers to 1100 micrometers; and   a plurality of cells encapsulated in the microparticles at a density of from 10 million cells per milliliter to 60 million cells per milliliter.   
     
     
         25 . The composition of  claim 24 , wherein average diameter is from 200 micrometers to 1100 micrometers across a largest dimension. 
     
     
         26 . The composition of  claim 25 , wherein the average diameter is from 500 micrometers to 1100 micrometers across a largest dimension. 
     
     
         27 . The composition of  claim 24 , wherein the microparticles comprise a spherical shape. 
     
     
         28 . The composition of  claim 27 , wherein the average measurement across a largest diameter is a microsphere diameter, and a coefficient of variance of the microsphere diameter is from 1% to 6%. 
     
     
         29 . The composition of  claim 28 , wherein an average roundness of the microparticles is greater than 0.95. 
     
     
         30 . The composition of  claim 24 , wherein the microparticles are rod shaped. 
     
     
         31 . The composition of  claim 30 , wherein the microparticles comprise an aspect ratio defined as rod length:rod diameter, and the aspect ratio is from 1:1 to 5:1. 
     
     
         32 . The composition of  claim 24 , wherein the microparticles are suspended in a carrier fluid, the carrier fluid comprising a hydrophobic fluid. 
     
     
         33 . The composition of  claim 24 , wherein the microparticles are suspended in a carrier fluid, the carrier fluid comprising a cell culture media. 
     
     
         34 . The composition of  claim 24 , wherein the density is from 30 million cells per milliliter precursor solution to 60 million cells per milliliter precursor solution. 
     
     
         35 . The composition of  claim 24 , wherein the plurality of cells encapsulated in the microparticles comprise a plurality of cell clusters. 
     
     
         36 . The composition of  claim 35 , wherein each cluster of the plurality of clusters comprises from 5 cells to 40 cells. 
     
     
         37 . The composition of  claim 24 , wherein the plurality of cells are mammalian cells. 
     
     
         38 . The composition of  claim 24 , wherein the plurality of cells comprise human induced pluripotent stem cells. 
     
     
         39 . The composition of  claim 24 , wherein the plurality of cells comprise endothelial cells. 
     
     
         40 . The composition of  claim 24 , wherein the plurality of cells comprise cancer cells. 
     
     
         41 . The composition of  claim 24 , wherein the microparticles comprise a photocrosslinkable polymer. 
     
     
         42 . The composition of  claim 40 , wherein the photocrosslinkable polymer comprises polyethylene glycol. 
     
     
         43 . The composition of  claim 40 , wherein the photocrosslinkable polymer comprises a natural material.