Microfluidic cell culture device

Abstract

Microfluidic devices for cell culturing and methods for using the same are disclosed. One device includes a substrate and membrane. The substrate includes a reservoir in fluid communication with a passage. A bio-compatible fluid may be added to the reservoir and passage. The reservoir is configured to receive and retain at least a portion of a cell mass. The membrane acts as a barrier to evaporation of the bio-compatible fluid from the passage. A cover fluid may be added to cover the bio-compatible fluid to prevent evaporation of the bio-compatible fluid.

1 . A microfluidic cell culture device comprising: 
 a substrate;    a reservoir formed in the substrate and having upper and lower portions, the upper portion being sized to permit the insertion and removal of a cell mass from the reservoir; and    a passage formed in the substrate and in fluid communication with the reservoir wherein at least one of the lower portion of the reservoir and the passage adjacent the lower portion is sized relative to the cell mass to retain at least a portion of the cell mass within the lower portion of the reservoir so that the cell mass can be directly removed from the lower portion through the upper portion.    
   
   
       2 . The device of  claim 1  wherein the lower portion of the reservoir is sized relative to the cell mass to retain at least a portion of the cell mass within the lower portion of the reservoir so that the cell mass can be directly removed from the lower portion through the upper portion.  
   
   
       3 . The device of  claim 2  wherein the lower portion of the reservoir has a width less than 250 micrometers to retain at least a portion of the cell mass within the reservoir.  
   
   
       4 . The device of  claim 2  wherein the lower portion of the reservoir has a width, wherein the cell mass is a denuded human zygote, and wherein the width is less than 140 micrometers to retain at least a portion of the cell mass within the reservoir.  
   
   
       5 . The device of  claim 2  wherein the lower portion of the reservoir has a width, wherein the cell mass is a denuded mammalian zygote, and wherein the width is less than 70 micrometers to retain at least a portion of the cell mass within the reservoir.  
   
   
       6 . The device of  claim 2  wherein the lower portion of the reservoir has a width, wherein the cell mass is a clump of mammalian cells, and wherein the width is less than 50 micrometers to retain at least a portion of the cell mass within the reservoir.  
   
   
       7 . The device of  claim 2  wherein the lower portion of the reservoir has a width, wherein the cell mass is a single mammalian cell, and wherein the width is less than  5  micrometers to retain at least a portion of the cell mass within the reservoir.  
   
   
       8 . The device of  claim 1  wherein the passage adjacent the lower portion is sized relative to the cell mass to retain at least a portion of the cell mass within the lower portion of the reservoir so that the cell mass can be directly removed from the lower portion through the upper portion.  
   
   
       9 . The device of  claim 8  wherein the passage adjacent the lower portion has a passage width and a passage height and wherein at least one of the passage height and the passage width is less than 250 micrometers to retain at least a portion of the cell mass within the reservoir.  
   
   
       10 . The device of  claim 8  wherein the passage adjacent the lower portion has a passage width and a passage height, wherein the cell mass is a denuded human zygote, and wherein at least one of the passage height and the passage width is less than 140 micrometers to retain at least a portion of the cell mass within the reservoir.  
   
   
       11 . The device of  claim 8  wherein the passage adjacent the lower portion has a passage width and a passage height, wherein the cell mass is a denuded mammalian zygote, and wherein at least one of the passage height and the passage width is less than 70 micrometers to retain at least a portion of the cell mass within the reservoir.  
   
   
       12 . The device of  claim 8  wherein the passage adjacent the lower portion has a passage width and a passage height, wherein the cell mass is a clump of mammalian cells, and wherein at least one of the passage height and the passage width is less than 50 micrometers to retain at least a portion of the cell mass within the reservoir.  
   
   
       13 . The device of  claim 8  wherein the passage adjacent the lower portion has a passage width and a passage height, wherein the cell mass is a single mammalian cell, and wherein at least one of the passage height and the passage width is less than 5 micrometers to retain at least a portion of the cell mass within the reservoir.  
   
   
       14 . The device of  claim 1  wherein a cross-section of the reservoir has a polygonal shape.  
   
   
       15 . The device of  claim 1  wherein the reservoir has a frusta-conical shape.  
   
   
       16 . The device of  claim 1  wherein an angle defined by opposite surfaces of the reservoir is between 30 degrees and 160 degrees inclusive.  
   
   
       17 . The device of  claim 1  wherein the upper portion has an upper width and the lower portion has a lower width and wherein the upper width is greater than the lower width.  
   
   
       18 . The device of  claim 1  wherein a surface of the reservoir tapers inwardly from the upper portion to the lower portion.  
   
   
       19 . The device of  claim 1  wherein the passage is U-shaped.  
   
   
       20 . The device of  claim 1  wherein the passage has a volume less than 1 microliter.