Hierarchical films having ultra low fouling and high recognition element loading properties

Abstract

Hierarchical films with structurally regulated functionalities through the integration of two-dimensional and three-dimensional structures to achieve ultra low nonspecific binding and high loading of molecular recognition elements, and methods for making and using the films.

1 . A surface-anchored polymer assembly, comprising:
 (a) a nonfouling first layer having a first layer density, wherein the first layer comprises a plurality of first polymers, wherein each is attached to a substrate; and   (b) a second layer having a second layer density, wherein the second layer comprises a plurality of second polymers and a plurality of recognition elements attached to the second polymers, wherein the recognition elements are attached throughout the entire second layer, wherein the second layer is attached to the first layer,   wherein the first layer density is greater than the second layer density.   
     
     
         2 . (canceled) 
     
     
         3 . The polymer assembly of  claim 1  further comprising one or more additional layers attached to the second layer. 
     
     
         4 - 5 . (canceled) 
     
     
         6 . The polymer assembly of  claim 1 , wherein the first layer has a fibrinogen binding level less than about 30 ng/cm 2 . 
     
     
         7 . The polymer assembly of  claim 1 , wherein the first layer has a lysozyme binding level less than about 30 ng/cm 2 . 
     
     
         8 - 9 . (canceled) 
     
     
         10 . The polymer assembly of  claim 1 , wherein the second layer is a crosslinked layer. 
     
     
         11 . The polymer assembly of  claim 1 , wherein the first polymers are grafted from the substrate. 
     
     
         12 . The polymer assembly of  claim 1 , wherein the first polymers are grafted to the substrate. 
     
     
         13 . The polymer assembly of  claim 1 , wherein the second polymers are grafted from the first polymers. 
     
     
         14 . (canceled) 
     
     
         15 . The polymer assembly of  claim 1 , wherein the first and second polymers are independently selected from the group consisting of charged polymers and copolymers and non-charged polymers and copolymers. 
     
     
         16 . The polymer assembly of  claim 1 , wherein the first and second polymers are independently selected from zwitterionic polymers and copolymers and mixed charge copolymers. 
     
     
         17 . The polymer assembly of  claim 1 , wherein the first and second polymers are independently selected from the group consisting of polysulfobetaines, polycarboxybetaines, polyphosphobetaines, peptides, and peptoids. 
     
     
         18 . The polymer assembly of  claim 1 , wherein the first and second polymers are independently selected from alkylene oxide polymers and copolymers, polysaccharide polymers and copolymers, acrylamide polymers and copolymers, or hydroxy-terminal polymers and copolymers. 
     
     
         19 . The polymer assembly of  claim 1 , wherein the first polymers or the second polymers are zwitterionic polymers having the formula:
   PB-[L 1 -(N + (R 2 )(R 3 ))-L 2 -AO 2   − -] n (X − ) n (M + ) n      wherein   PB is the polymer backbone having n pendant zwitterionic groups;   R 2  and R 3  are independently selected from the group consisting of hydrogen, alkyl, and aryl, or taken together with the nitrogen to which they are attached form a cationic center;   L 1  is a linker that covalently couples the cationic center [N + (R 5 )(R 6 )] to the polymer backbone;   L 2  is a linker that covalently couples the anionic center [A(═O)—O − ] to the cationic center;   A is C, S, SO, P, or PO;   M +  is an optional counter ion associated with the (A=O)O −  anionic center;   X −  is an optional counter ion associated with the cationic center; and   n is an integer from 1 to about 10,000.   
     
     
         20 . The polymer assembly of  claim 1 , wherein the first polymers or the second polymers are mixed charge copolymers having the formula:
   PB-[L 3 -(N + (R 6 )(R 7 )(R 8 )X − ] n [L 4 -A 2 O 2   − M + ] p      wherein   PB is the polymer backbone having n pendant cationic groups and p pendant anionic groups;   R 6 , R 7 , and R 8  are independently selected from hydrogen, alkyl, and aryl, or taken together with the nitrogen to which they are attached form a cationic center;   A(═O)—OM) is an anionic center, wherein A is C, S, SO, P, or PO, and M +  is an optional counter ion;   L 3  is a linker that covalently couples the cationic center [N + (R 6 )(R 7 )(R 8 )] to the polymer backbone;   L 4  is a linker that covalently couples the anionic center [A(═O)—OM] to the polymer backbone;   X −  is an optional counter ion associated with the cationic center;   n is an integer from 1 to about 10,000; and   p is an integer from 1 to about 10,000.   
     
     
         21 . The polymer assembly of  claim 1 , wherein the substrate is selected from metal and metal oxide surfaces, ceramic surfaces, synthetic and natural polymeric surfaces, glass surfaces, fiber glass surfaces, silicon/silica surfaces, carbon-based material surfaces, cell surfaces, or macromolecule surfaces. 
     
     
         22 . The polymer assembly of  claim 1 , wherein the substrate is the surface of a diagnostic device, a medical device, a separation device, a targeting delivery carrier, a scaffold, or a marine coating. 
     
     
         23 . A method for making a surface-anchored polymer assembly, comprising:
 (a) forming a first layer having a first layer density on a substrate; and   (b) forming a second layer on the first layer, the second layer having a second density,   wherein the first layer density is greater than the second layer density.   
     
     
         24 . The method of  claim 23  further comprising attaching a plurality of recognition elements to the second layer. 
     
     
         25 . A method for determining the presence of an analyte in a sample, comprising:
 (a) contacting a sample with a polymer assembly of  claim 1 , wherein the recognition element has a specific binding affinity for the analyte; and   (b) interrogating the polymer assembly to determine whether the analyte has bound to the film.