Polycationic quaternary ammonium polymer coatings for immobilizing biological samples

Abstract

The present invention is directed to a pre-coated substrate, such as a slide, that is useful for immobilizing a sample. The invention is further provides methods of preparing such pre-coated substrates and methods of analyzing biological samples immobilized on such pre-coated substrate. The substrate is coated with a polycationic polymeric coating material specifically selected such that that coated substrate exhibits increased stability and prolonged shelf-life. Preferred polymeric coating materials include allylic or vinylic polymers having cationic groups thereon and having no more than a small percentage of peptidic monomeric linkages, particularly polydiallyldimethylammonium (PDDA).

1 .- 48 . (canceled) 
     
     
         49 . A coated substrate for immobilizing a biological sample for analysis, comprising:
 a substrate, wherein the substrate is a glass slide; and   a coating comprising a non-peptidic quaternary ammonium polymeric material having an average molecular weight greater than 350,000 Da, wherein the coating allows cells in a biological sample to be immobilized directly thereon when brought into contact with the biological sample.   
     
     
         50 . The coated substrate of  claim 49 , wherein the non-peptidic quaternary ammonium polymeric material comprises a monomer selected from the group consisting of diallyldimethylammonium, methylacrylamidopropyltrimethylammonium, methacryloyloxyethyltrimethylammonium, 4-vinyl-benzyltrimethyl ammonium, acryloxyethyldimethylbenzyl ammonium, acryloxyethyltrimethyl ammonium, dimethylaminoethylmethacrylate, methacryloxyethyldimethyl ammonium, methacryloxyethyltrimethylbenzylammonium, trimethyl-2-methacryloylethylammonium, trimethyl-2-methacrylaminopropylammonium, or a mixture thereof. 
     
     
         51 . The coated substrate of  claim 49 , wherein the non-peptidic quaternary ammonium polymeric material is a homopolymer. 
     
     
         52 . The coated substrate of  claim 49 , wherein the non-peptidic quaternary ammonium polymeric material is hydrophilic. 
     
     
         53 . The coated substrate of  claim 49 , wherein the non-peptidic quaternary ammonium polymeric material is polydiallyldimethylammonium (PDDA). 
     
     
         54 . The coated substrate of  claim 50 , wherein the non-peptidic quaternary ammonium polymeric material has an average molecular weight of about 400,000 Da to about 500,000 Da. 
     
     
         55 . The coated substrate of  claim 49 , wherein the coating does not comprise poly-L-lysine (PLL). 
     
     
         56 . The coated substrate of  claim 49 , wherein the substrate is a microscope slide. 
     
     
         57 . The coated substrate of  claim 49 , wherein the coating has a layer thickness of about 0.005 μm to about 500 μm. 
     
     
         58 . The coated substrate of  claim 49 , wherein the coating has a layer thickness of about 1μm to about 50 μm. 
     
     
         59 . The coated substrate of  claim 49 , wherein the biological sample comprises a fluid sample, a tissue sample, or a mixture thereof. 
     
     
         60 . The coated substrate of  claim 49 , wherein the cells comprise human cells. 
     
     
         61 . The coated substrate of  claim 49 , wherein the cells comprise cervical carcinoma cells. 
     
     
         62 . The coated substrate of  claim 49 , wherein the non-peptidic, quaternary ammonium polymeric material is applied to the substrate as a solution, wherein the non-peptidic, quaternary ammonium polymeric material is present in the solution at a concentration of about 0.01% (w/v) to about 10% (w/v). 
     
     
         63 . The coated substrate of  claim 62 , wherein the non-peptidic, quaternary ammonium polymeric material is present in the solution at a concentration of about 0.25%. 
     
     
         64 . The coated substrate of  claim 62 , wherein the solution has a pH of about 8 to about 14. 
     
     
         65 . The coated substrate of clam 62, wherein the solution has a pH of about 9.2. 
     
     
         66 . The coated substrate of  claim 49 , wherein the coating is capable of allowing adherence of the cells in the biological sample following at least five weeks of storage. 
     
     
         67 . The coated substrate of  claim 65 , wherein the coating is capable of allowing adherence of the cells in the biological sample following 16 weeks of storage. 
     
     
         68 . The coated substrate of  claim 65 , wherein the storage comprises storage at about room temperature to about 45° C.