Systems and methods for improved performance of fluidic and microfluidic systems

Abstract

Systems and methods for improved flow properties in fluidic and microfluidic systems are disclosed. The system includes a microfluidic device having a first microchannel, a fluid reservoir having a working fluid and a pressurized gas, a pump in communication with the fluid reservoir to maintain a desired pressure of the pressurized gas, and a fluid-resistance element located within a fluid path between the fluid reservoir and the first microchannel. The fluid-resistance element includes a first fluidic resistance that is substantially larger than a second fluidic resistance associated with the first microchannel.

What is claimed is: 
     
         1 . A method of flow, comprising:
 a) providing: a microfluidic device comprising a fluid-resistance element and a fluid reservoir connected to a microchannel, wherein the fluid-resistance element has a first fluidic resistance that is at least about 100 times greater than a second fluidic resistance associated with the microchannel;   b) introducing cells in said microchannel; and   c) forcing the fluid through the fluid-resistance element such that said fluid flows through said microchannel at a flow rate.   
     
     
         2 . The method of  claim 1 , wherein the fluid is forced in step c) with pressurized gas. 
     
     
         3 . The method of  claim 1 , wherein the fluid-resistance element comprises a fluid path channeled into a substrate. 
     
     
         4 . The method of  claim 3 , wherein the substrate of said fluid-resistance element comprises an elongated fluid path, the first fluidic resistance being created by the elongated fluid path. 
     
     
         5 . The method of  claim 4 , wherein the elongated fluid path undergoes multiple windings so as to create said elongated fluid path. 
     
     
         6 . The method of  claim 1 , further comprising a cartridge interfaced with said microfluidic device. The method of  claim 1 , wherein the gas is substantially insoluble in the fluid. 
     
     
         8 . The method of  claim 1 , wherein the gas is a mixture of gases, the mixture including a gas that is substantially insoluble in the fluid. 
     
     
         9 . The method of  claim 1 , wherein the fluid-resistance element is removably connected to the microchannel between the microfluidic device and the fluid reservoir. 
     
     
         10 . A method, comprising:
 a) providing
 i) a microfluidic device having a first microchannel, 
 ii) a fluid reservoir comprising a working fluid and being disposed outside of the microfluidic device, 
 iii) a fluid line coupled to the fluid reservoir for delivering the working fluid to or from the microfluidic device; and 
 iv) a fluid-resistance element coupled to the microfluidic device, the fluid-resistance element having a first fluidic resistance that is about 10-50,000 times greater than a second fluidic resistance associated with the microfluidic device; and 
   b) forcing the working fluid through the fluid-resistance element such that said working fluid flows through said microchannel at a flow rate.   
     
     
         11 . The method of  claim 10 , wherein the working fluid comprises at least one component selected from the group consisting of media, suspensions of cells, particulates, proteins, chemicals, contaminant, pollutant, pharmaceutical and combinations thereof. 
     
     
         12 . The method of  claim 10 , wherein said fluid-resistance element comprises a substrate having an elongated fluid path. 
     
     
         13 . The method of  claim 10 , wherein the working fluid is forced in step d) with pressurized gas.