Forming or patterning composite microstructures using microfluidics

Abstract

Techniques comprising systems and methods for forming or pattering microstructures using microfluidics are described. A target structure can include a microchannel passage with a chamber into which a light hardenable material can be injected and selectively exposed to light to adhere to a desired location of a substrate. Unhardened material can be washed out of the chamber. One or more subsequent cycles can repeat the process using the same or a different material. A variety of composite microstructures can be created, including structures encapsulating viable living cells, such as for cell study or tissue engineering.

1 - 25 . (canceled) 
     
     
         26 . A method for forming a composite structure, the method comprising:
 flowing a first precursor solution into an assembly region;   exposing at least a first portion of the assembly region to light such that the first precursor solution in at least said first portion of the assembly region is polymerized into a first polymer section;   flowing a second precursor solution into the assembly region; and   exposing at least a second portion of the assembly region to light such that the second precursor solution in at least said second portion of the assembly region is polymerized into a second polymer section,   wherein the first polymer section has a material property different from that of the second polymer section, and   the exposing at least a first portion to light and the exposing at least a second portion to light are performed by using a maskless system to focus light to a spot in said assembly region so as to form a pattern by the respective exposing.   
     
     
         27 . A method for forming a composite structure, the method comprising:
 flowing a first precursor solution into an assembly region;   masklessly exposing at least a first portion of the assembly region to light such that the first precursor solution in at least said first portion of the assembly region is polymerized into a first polymer section;   flowing a second precursor solution into the assembly region; and   masklessly exposing at least a second portion of the assembly region to light such that the second precursor solution in at least said second portion of the assembly region is polymerized into a second polymer section,   wherein the first polymer section has a material property different from that of the second polymer section, and   the masklessly exposing at least a first portion to light and the masklessly exposing at least a second portion to light are performed by using a microscope to focus light to a spot in said assembly region so as to form a pattern by the respective exposing.   
     
     
         28 . The method of  claim 26 , wherein the spot of focused light is smaller than the assembly region. 
     
     
         29 . The method of  claim 27 , wherein the spot of focused light is smaller than the assembly region. 
     
     
         30 . The method of  claim 26 , wherein the spot of focused light has a diameter of 40 μm or less. 
     
     
         31 . The method of  claim 27 , wherein the spot of focused light has a diameter of 40 μm or less. 
     
     
         32 . The method of  claim 26 , wherein the maskless system comprises a confocal laser microscope. 
     
     
         33 . The method of  claim 27 , wherein the microscope is a confocal laser microscope. 
     
     
         34 . The method of  claim 26 , wherein the maskless system comprises a fluorescence microscope. 
     
     
         35 . The method of  claim 27 , wherein the microscope is a fluorescence microscope. 
     
     
         36 . The method of  claim 26 , wherein living cells are suspended in at least one of the first and second precursor solutions during the exposing. 
     
     
         37 . The method of  claim 27 , wherein living cells are suspended in at least one of the first and second precursor solutions during the exposing. 
     
     
         38 . The method of  claim 36 , wherein the living cells comprise fibroblasts, and at least 95% of the fibroblasts are viable immediately after polymerization of the respective precursor solution. 
     
     
         39 . The method of  claim 37 , wherein the living cells comprise fibroblasts, and at least 95% of the fibroblasts are viable immediately after polymerization of the respective precursor solution. 
     
     
         40 . The method of  claim 36 , wherein the living cells comprise 3T3 fibroblasts. 
     
     
         41 . The method of  claim 37 , wherein the living cells comprise 3T3 fibroblasts. 
     
     
         42 . A method for forming a composite structure, the method comprising:
 flowing a precursor solution including one or more living cells into an assembly region;   focusing light from a microscope to a spot so as to expose a portion of the assembly region such that the precursor solution is polymerized into a first polymer section with the one or more living cells therein.   
     
     
         43 . The method of  claim 42 , further comprising repeating said flowing and focusing with one or more subsequent precursor solutions, at least one of the polymer sections formed from the subsequent precursor solutions having a material property different from said first polymer section. 
     
     
         44 . The method of  claim 42 , wherein the focusing is such that a diameter of the spot of light from the microscope is 40 μm or less. 
     
     
         45 . The method of  claim 42 , wherein the microscope is one of a confocal laser microscope and a fluorescence microscope.