Non-thermosensitive medium for analysing species inside a channel

Abstract

The invention concerns a non-thermosensitive liquid medium for analyzing, purifying or separating species in a channel and comprising at least a polymer consisting of several polymeric segments. The invention is characterised in that the polymer is of the irregular block-copolymer or irregular comb-like polymer type and has on the average at least three junction points between polymeric segments of different chemical or topological nature. The invention also concerns methods for analyzing, purifying or separating species using a non-thermosenstive separation medium.

1 . A non-thermosensitive liquid medium for analyzing, purifying or separating species inside a channel, and comprising at least one polymer composed of several polymer segments, characterized in that said polymer is of the irregular block copolymer type or irregular comb polymer type and has on average at least three junction points established between polymer segments of different chemical or topological nature.  
     
     
         2 . The medium as claimed in  claim 1 , characterized in that all the segments of at least one type of chemical or topological nature forming part of the composition of said polymer have a polydispersity of at least 1.5.  
     
     
         3 . The medium as claimed in  claim 1  or  2 , characterized in that the segments of each of the types of chemical or topological nature forming part of the composition of said polymer have a polydispersity of at least 1.5.  
     
     
         4 . The medium as claimed in  claim 2  or  3 , characterized in that said polydispersity is greater than 1.8.  
     
     
         5 . The medium as claimed in any one of the preceding claims, characterized in that said polymer has an average molecular mass of greater than 50 000 and preferably greater than 300 000.  
     
     
         6 . The medium as claimed in any one of  claims 1  to  5 , characterized in that said polymer shows specific affinity for the walls of said channel.  
     
     
         7 . The medium as claimed in  claim 6 , characterized in that said polymer has at least one type of polymer segments showing, within the separating medium, specific affinity for the wall, and at least one type of polymer segment showing in said medium less or no affinity for the wall.  
     
     
         8 . The medium as claimed in  claim 6  or  7 , characterized in that all the segments showing specific affinity for the wall represent between 2% and 80% by mass of the average total molar mass of said polymer.  
     
     
         9 . The medium as claimed in one of the preceding claims, characterized in that the polymer shows specific affinity for one or more analytes.  
     
     
         10 . The medium as claimed in  claim 9 , characterized in that the polymer bears nucleotides or polypeptides of determined sequence.  
     
     
         11 . The medium as claimed in  claim 9 , characterized in that the polymer is combined with a protein, a protein fraction, a protein complex and/or an acidic or basic function.  
     
     
         12 . The medium as claimed in one of the preceding claims, characterized in that all the polymer segments of at least one type of chemical or topological nature have on average a number of atoms of greater than 75, and preferably greater than 210, or have a molecular mass of greater than 1 500 and preferably greater than 4 500.  
     
     
         13 . The medium as claimed in any one of the preceding claims, characterized in that the various types of polymer segments of which said polymer is composed have on average an average number of atoms of greater than 75, and preferably greater than 210, or have a molecular mass of greater than 1 500 and preferably greater than 4 500.  
     
     
         14 . The medium as claimed in any one of the preceding claims, characterized in that the polymer has on average a number of junction points of between 4 and 100.  
     
     
         15 . The medium as claimed in any one of the preceding claims, characterized in that the polymer is a block copolymer containing on average at least four polymer segments.  
     
     
         16 . The medium as claimed in any one of the preceding claims, characterized in that the polymer is a comb polymer containing on average at least two side chains.  
     
     
         17 . The medium as claimed in any one of the preceding claims, characterized in that the polymer comprises at least one type of segment chosen from polyethers, polyesters, for instance polyglycolic acid, soluble random homopolymers and copolymers of the polyoxyalkylene type, for instance polyoxypropylene, polyoxybutylene or polyoxyethylene, polysaccharides, polyvinyl alcohol, polyvinylpyrrolidone, polyurethanes, polyamides, polysulfonamides, polysulfoxides, polyoxazoline, polystyrene sulfonate, and substituted or unsubstituted acrylamide, methacrylamide and allyl polymers and copolymers.  
     
     
         18 . The medium as claimed in any one of the preceding claims, characterized in that said polymer comprises at least one polymer chosen from: 
 copolymers of the comb copolymer type, the skeleton of which is of dextran, acrylamide, acrylic acid, acryloylaminoethanol or (N,N)-dimethylacrylamide type and onto which are grafted side segments of acrylamide, substituted acrylamide or (N,N)-dimethylacrylamide (DMA) type, or of the DMA/allyl glycidyl ether (AGE) copolymer type, or of homopolymer or copolymer of oxazoline or of oxazoline derivatives;    non-thermosensitive copolymers of the irregular sequential copolymer type having along their skeleton an alternation of segments of polyoxyethylene type and of segments of polyoxypropylene type, or an alternation of segments of polyoxyethylene type and of segments of polyoxybutylene type, or an alternation of segments of polyethylene and of segments of polyether type that are more hydrophobic than polyoxyethylene;    copolymers of the irregular sequential block copolymer type having along their skeleton an alternation of segments of acrylamide, acrylic acid, acryloylaminoethanol or dimethylacrylamide type, on the one hand, and segments of (N,N)-dimethylacrylamide (DMA) type, or of DMA/allyl glycidyl ether (AGE) copolymer type, or of homopolymer or copolymer of oxazoline or of oxazoline derivatives;    polymers of the irregular comb polymer type, the skeleton of which is of the agarose, acrylamide, substituted acrylamide, acrylic acid, acryloylaminoethanol, dimethylacrylamide (DMA), or allyl glycidyl ether (AGE) polymer type, of DMA/AGE random copolymer type, of oxazoline and oxazoline derivative, of dextran, of methylcellulose, of hydroxyethylcellulose, of modified cellulose, of polysaccharide or of ether oxide type, and onto which are grafted side segments of agarose, acrylamide, substituted acrylamide, acrylic acid, acryloylaminoethanol, dimethylacrylamide (DMA), or allyl glycidyl ether (AGE) polymer type, of DMA/AGE random copolymer type, of oxazoline and oxazoline derivative, of dextran, of methylcellulose, of hydroxyethylcellulose, of modified cellulose, of polysaccharide or of ether oxide type;    copolymers of the irregular comb copolymer type, the skeleton of which is of the acrylamide, substituted acrylamide, acrylic acid, acryloylaminoethanol, dimethylacrylamide (DMA), or allyl glycidyl ether (AGE) polymer type, of DMA/AGE random copolymer type, of oxazoline and oxazoline derivative, of dextran, of agarose, of methylcellulose, of hydroxyethylcellulose, of modified cellulose, of polysaccharide or of ether oxide type, and bears short-chain hydrophobic side segments such as alkyl chains, aromatic derivatives, fluoroalkyls, silanes or fluorosilanes.    
     
     
         19 . The use of a medium as claimed in one of  claims 1  to  18 , for separating, purifying, filtering or analyzing species chosen from molecular or macromolecular species, biological macromolecules of nucleic acid type, their synthesis analogs, proteins, polypeptides, glycopeptides and polysaccharides, organic molecules, synthetic macromolecules or particles such as mineral particles, lattices, cells or organelles.  
     
     
         20 . The use as claimed in  claim 19  or the use of a medium as claimed in one of  claims 1  to  18 , in a channel of which at least one dimension is submillimetric.  
     
     
         21 . The use as claimed in  claim 19  or  20  or the use of a medium as claimed in one of  claims 1  to  18 , for electrokinetic separations.  
     
     
         22 . The use as claimed in one of  claims 19  to  21  or the use of a medium as claimed in one of  claims 1  to  18 , for diagnosis, gene typing, and high-throughput screening, quality control, or for detecting the presence of genetically modified organisms in a product.  
     
     
         23 . A process for separating, analyzing and/or identifying species contained in a sample, characterized in that it comprises 
 a/ the filling of the channel of a separating device with a separating medium as claimed in one of  claims 1  to  18 ,    b/ the introduction of said sample containing said species into one end of said channel,    c/ the application of an external field intended to move certain species contained in the sample, and    d/ the recovery of said species or the detection of their passage at a point along the channel that is different from the point of introduction of the sample.