Microparticle organization

Abstract

Methods and compositions are described for organizing nanoparticles or microparticles into nanostructures or microstructures using collagen as a template.

1 . A method of organizing nanoparticles into a nanostructure, comprising:
 contacting a collagen template with a still solution comprising (i) collagen monomers in liquid crystalline phase and (ii) nanoparticles; and   assembling the collagen monomers into an ordered collagen structure by neutralizing the solution in contact with the collagen template, the ordered collagen structure directing the organization of the nanoparticles into a nanostructure.   
     
     
         2 . The method of  claim 1 , further comprising crosslinking functional groups on the nanoparticles to stabilize the nanostructure. 
     
     
         3 . The method of  claim 1 , further comprising removing the ordered collagen structure from the nanostructure. 
     
     
         4 . The method of  claim 3 , wherein removing the organized collagen structure comprises digestion with collagenase. 
     
     
         5 . The method of  claim 1 , wherein the nanostructure is a single-walled carbon nanotube. 
     
     
         6 . The method of  claim 1 , wherein the nanostructure is a multi-walled carbon nanotube. 
     
     
         7 . The method of  claim 1 , wherein the still solution comprises about 1% to about 99% collagen monomers. 
     
     
         8 . The method of  claim 1 , wherein the still solution comprises about 1% to about 99% nanoparticles. 
     
     
         9 . The method of  claim 1 , wherein the solution comprises a ratio of collagen monomers to nanoparticles of about 1% to about 99%. 
     
     
         10 . The method of  claim 1 , wherein the collagen monomers comprise a nematic phase. 
     
     
         11 . The method of  claim 1 , wherein the collagen monomers comprise a smectic phase. 
     
     
         12 . The method of  claim 1 , wherein the collagen monomers comprise a cholesteric phase. 
     
     
         13 . The method of  claim 1 , wherein the solution comprises about 30 mg/ml to about 500 mg/ml collagen monomers. 
     
     
         14 . The method of  claim 1 , wherein the neutralizing step comprises adjusting the solution to a pH of about 5 to about 10. 
     
     
         15 . The method of  claim 14 , further comprising neutralizing the solution in contact with the collagen template at about 10° C. to about 39° C. 
     
     
         16 . The method of  claim 1 , wherein the collagen template comprises one or more guidance structures. 
     
     
         17 . The method of  claim 16 , wherein the one or more guidance structures are one or more internal guidance structures and the collagen template is placed in a stationary position within the solution. 
     
     
         18 . The method of  claim 17 , wherein the one or more internal guidance structures comprise a high aspect ratio geometry. 
     
     
         19 . The method of  claim 18 , wherein the one or more internal guidance structures comprise a minor length scale of between about 14 nm and about 20 μm. 
     
     
         20 . The method of  claim 17 , wherein the one or more internal guidance structures comprise a biodegradable material. 
     
     
         21 . The method of  claim 1 , wherein the collagen template comprises a plurality of external guidance structures having an interstructure distance of about 2 μm to about 200 μm. 
     
     
         22 . The method of  claim 1 , wherein the collagen template comprises a cylindrical tube, two concentric cylindrical tubes, or two concentric hemispheres. 
     
     
         23 . The method of  claim 22 , wherein the collagen template comprises a cylindrical tube having an inner diameter of about 100 μm to about 1 mm. 
     
     
         24 . The method of  claim 22 , wherein the collagen template comprises two concentric cylinders with a gap width of about 2 μm to about 4 mm. 
     
     
         25 . The method of  claim 22 , wherein the collagen template comprises two concentric hemispheres with a gap width of about 2 μm to about 4 mm. 
     
     
         26 . The method of  claim 1 , wherein the collagen template comprises one or more internal guidance structures and one or more external guidance structures. 
     
     
         27 . The method of  claim 1 , wherein the solution comprises one or more co-nonsolvency agents. 
     
     
         28 . The method of  claim 1 , wherein the solution further comprises a collagen binding agent. 
     
     
         29 . The method of  claim 1 , further comprising applying an electric charge to the contacted collagen template. 
     
     
         30 . The method of  claim 1 , wherein the ordered collagen structure is about 100 μm to about 30 cm in length.