Micro-channel design features that facilitate centripetal fluid transfer

Abstract

Microfluidic devices, assemblies, and systems are provided, as are methods of manipulating micro-sized samples of fluids. Microfluidic devices having a plurality of specialized processing features that facilitate centripetal fluid transfer are also provided.

1 . A microfluidic device comprising: 
 a substrate having a first surface, an opposite second surface, and a thickness;    an input port formed in at least one of the first surface or second surface;    a manifold formed in the substrate and in fluid communication with the input port, the manifold including a feed channel, an input channel in fluid communication between the input port and the feed channel, the feed channel extending in a first direction from a first end at the input channel to an opposite second end, and a plurality of branch channels each branching off the feed channel between the first and second ends, each branch channel extending in a direction that is parallel to the first surface of the substrate and each terminating at a closed end; and    a plurality of closed chambers formed in the substrate, at least one of the closed chambers adjacent a respective closed end of the plurality of branch channels.    
     
     
         2 . The microfluidic device of  claim 1 , wherein the plurality of branch channels are parallel to one another.  
     
     
         3 . The microfluidic device of  claim 1 , wherein the volume of each of the plurality of branch channels is about equal to the volume of each of the other branch channels.  
     
     
         4 . The microfluidic device of  claim 1 , wherein the volume of at least one of the plurality of branch channels is greater or less than the volumes of the other branch channels.  
     
     
         5 . The microfluidic device of  claim 1 , wherein the length of each of the plurality of branch channels is about equal.  
     
     
         6 . The microfluidic device of  claim 1 , wherein each of the plurality of branch channels is in interruptible fluid communication with a respective pathway having at least one processing chamber, and a valve is provided between each of the branch channels and its respective at least one processing chamber.  
     
     
         7 . The microfluidic device of  claim 1 , wherein each of the plurality of branch channels has a valve and the manifold contains a first volume of fluid, and wherein the first volume of fluid is about equal to the collective volume of the plurality of branch channel volumes.  
     
     
         8 . The microfluidic device of  claim 1 , further comprising a cover in contact with the first surface of the substrate.  
     
     
         9 . The microfluidic device of  claim 6 , wherein each of the at least one processing chamber has a reagent disposed therein.  
     
     
         10 . The microfluidic device of  claim 9  having multiple processing channels, wherein at least one of the processing chambers has a different reagent disposed therein than the other processing chambers.  
     
     
         11 . The microfluidic device of  claim 1 , further including an input channel in fluid communication with and between the input port and the feed channel.  
     
     
         12 . The microfluidic device of  claim 1 , wherein each of the plurality of branch channels extends in a direction that is parallel to the first surface of the substrate.  
     
     
         13 . The microfluidic device of  claim 1 , wherein each of the plurality of branch channels extends in a direction that is normal to the first surface of the substrate.  
     
     
         14 . The microfluidic device of  claim 1 , wherein the plurality of branch channels includes at least about 3 branch channels.  
     
     
         15 . The microfluidic device of  claim 1 , wherein the plurality of branch channels includes at least 48 branch channels.  
     
     
         16 . The microfluidic device of  claim 1 , wherein the plurality of branch channels includes at least 96 branch channels.  
     
     
         17 . The microfluidic device of  claim 1 , wherein each of the plurality of branch channels has a volume, and the collective volume of the plurality of branch channels is from about 5 μl to about 100 μl.  
     
     
         18 . The microfluidic device of  claim 1 , wherein the input port comprises a teardrop-shaped input port having a wide end and a narrow end, and the narrow end is in fluid communication with the feed channel.  
     
     
         19 . The microfluidic device of  claim 1 , wherein the substrate further comprises at least one alignment pinhole formed therein.  
     
     
         20 . The microfluidic device of  claim 1 , wherein each of the plurality of branch channels extends in a direction normal to the feed channel.