Charge conversional ternary polyplex

Abstract

Disclosed is a polymer composite (polyplex) that contains nucleic acid, a cationic polymer, and an anionic polymer. The anionic polymer covers the surface of the composite comprising the cationic polymer and nucleic acid, has a negative charge at neutral pH, and can change so as to have a positive charge at mildly acidic pH.

1 . An anionic polymer represented by the following Formula (1): 
       
         
           
           
               
               
           
         
         [wherein, R 11  and R 12  independently represent a hydrogen atom, or an optionally substituted linear or branched alkyl group with a carbon number of 1-12, 
         R 13  represents a conjugate of a residue derived from an amine compound having a primary amine, and a compound represented by Formula (I) below: 
       
       
         
           
           
               
               
           
         
         (wherein, R a  and R b  independently represent a hydrogen atom, or an optionally substituted alkyl group, alkenyl group, cycloalkyl group, aryl group, aralkyl group, acyl group, heterocyclic group, heterocyclic alkyl group, hydroxy group, alkoxy group or aryloxy group, and R a  and R b  may bind to each other to form an aromatic ring or a cycloalkyl ring with the carbon atoms to which they are each bound, where the binding between the carbon atoms to which R a  and R b  are each bound is either a single bond or a double bond) or a derivative thereof, 
         m1 represents an integer of 10-500, and 
         m2 represents an integer of 1-5]. 
       
     
     
         2 . The anionic polymer according to  claim 1 , wherein the residue derived from an amine compound having a primary amine is a group represented by the following General Formula (11):
   —NH—(CH 2 ) r —X 11   (11)
   (wherein, X 11  represents an amine compound residue derived from primary, secondary or tertiary amine compound or quaternary ammonium salt, and r represents an integer of 0-5), or a group represented by the following General Formula (12):
   —[NH—(CH 2 ) s1 ] t1 —X 12   (12)
 
   (wherein, X 12  is synonymous with X 11 , and s1 and t1, independently from each other and independently between [NH—(CH 2 ) s1 ] units, represent integers of 1-5 and 2-5, respectively).   
     
     
         3 . The anionic polymer according to  claim 1 , wherein the residue derived from an amine compound having a primary amine is represented by —NH—NH 2  or —NH—(CH 2 ) 2 —NH—(CH 2 ) 2 —NH 2 . 
     
     
         4 . The anionic polymer according to  claim 1 , wherein the compound represented by Formula (I) above is at least one type of the compounds represented by Formula (Ia)-(Ig) below: 
       
         
           
           
               
               
           
         
       
     
     
         5 . A polymer complex comprising a nucleic acid, a cationic polymer and the anionic polymer according to any one of  claims 1 - 4 . 
     
     
         6 . The polymer complex according to  claim 5 , wherein the nucleic acid is plasmid DNA or siRNA. 
     
     
         7 . The polymer complex according to  claim 6 , wherein the cationic polymer is any compound selected from the group consisting of:
 a compound represented by the following Formula (2):   
       
         
           
           
               
               
           
         
         [wherein, R 21  and R 22  independently represent a hydrogen atom or an optionally substituted linear or branched alkyl group with a carbon number of 1-12, R 23  represents a residue derived from an amine compound having a primary amine, m3 represents an integer of 10-500, and m4 represents an integer of 1-5]; 
         a compound represented by the following Formula (3): 
       
       
         
           
           
               
               
           
         
         [wherein, R 31  and R 32  are synonymous with R 21  and R 22 , respectively, R 33  represents an optionally substituted saturated or unsaturated linear or branched aliphatic hydrocarbon group or steroloxycarbonyl group with a carbon number of 11-27, m5 and m6 independently represent an integer of 0-500 (provided that the sum of m5 and m6 is an integer of 10-500), m7 represents an integer of 1-5, m8 represents an integer of 1-5, and the sign “/” indicates that the sequential order of the (m5+m6) numbers of monomer units on both sides of the sign are arbitrary]; 
         a compound represented by the following Formula (4): 
       
       
         
           
           
               
               
           
         
         [wherein, R 41  and R 42  are synonymous with R 21  and R 22 , respectively, R 43  is synonymous with R 33 , R 44  is synonymous with R 23 , m9 and m10 are synonymous with m5 and m6, respectively, m11 and m12 are synonymous with m7 and m8, respectively, and the sign “/” is synonymous with the same above]; and 
         a compound represented by the following Formula (5): 
       
       
         
           
           
               
               
           
         
         [wherein, R 51  and R 52  are synonymous with R 21  and R 22 , respectively, R 53  and R 54  are synonymous with R 23 , L 1  represents NH, CO, a group represented by the following General Formula (13):
   —(CH 2 ) p1 —N—  (13)
 
 
         (wherein, p1 represents an integer of 1-6), or a group represented by the following General Formula (14):
   -L 2a -(CH 2 ) q1 -L 3a -  (14)
 
 
         (wherein, L 2a  represents OCO, OCONH, NHCO, NHCOO, NHCONH, CONH or COO, L 3a  represents NH or CO, and q1 represents an integer of 1-6), m13, m14 and m15 independently represent an integer of 0-500 (provided that the sum of m13, m14 and m15 is an integer of 10-500), m16 and m17 are synonymous with m7 and m8, respectively, n represents an integer of 0-500, and the sign “/” indicates that the sequential order of the (m13+m14+m15) numbers of monomer units on both sides of the sign are arbitrary]. 
       
     
     
         8 . A device for delivering a nucleic acid into a cell, comprising the polymer complex according to  claim 5 . 
     
     
         9 . A kit for delivering a nucleic acid into a cell, comprising the polymer complex according to  claim 5 .