Nucleic acid mediated electron transfer

Abstract

The present invention provides for the selective covalent modification of nucleic acids with redox active moieties such as transition metal complexes. Electron donor and electron acceptor moieties are covalently bound to the ribose-phosphate backbone of a nucleic acid at predetermined positions. The resulting complexes represent a series of new derivatives that are bimolecular templates capable of transferring electrons over very large distances at extremely fast rates. These complexes possess unique structural features which enable the use of an entirely new class of bioconductors and photoactive probes.

1 . A phosphoramidite nucleoside comprising a covalently attached electron transfer moiety.  
     
     
         2 . A nucleoside comprising: 
 a) a covalently attached electron transfer moiety; and    b) a phosphoramidite moiety.    
     
     
         3 . A nucleoside according to claims  1  or  2  wherein said electron transfer moiety is attached to the ribose of said nucleoside.  
     
     
         4 . A nucleoside according to  claim 3  wherein said electron transfer moiety is attached to said ribose via a linker at the 2′ position.  
     
     
         5 . A nucleoside according to claims  1  or  2  wherein said electron transfer moiety is a transition metal complex.  
     
     
         6 . A nucleoside according to  claim 5  wherein said transition metal complex comprises ruthenium.  
     
     
         7 . A nucleoside according to  claim 5  wherein said transition metal complex comprises iron.  
     
     
         8 . A nucleoside according to  claim 5  wherein said transition metal complex comprises cobalt.  
     
     
         9 . A method of making a nucleic acid comprising a covalently attached electron transfer moiety, said method comprising: 
 a) providing a phosphoramidite nucleoside comprising a covalently attached electron transfer moiety; and    b) incorporating said phosphoramidite nucleoside in a synthetic reaction to form a nucleic acid with a covalently attached electron transfer moiety.    
     
     
         10 . A method according to  claim 9  wherein said synthetic reaction is a solid-phase synthetic reaction.  
     
     
         11 . A method according to  claim 9  wherein said electron transfer moiety is attached to the ribose of said nucleoside.  
     
     
         12 . A method according to  claim 9  wherein said electron transfer moiety is attached to said ribose via a linker at the 2′ position.  
     
     
         13 . A method according to  claim 9  wherein said electron transfer moiety is a transition metal complex.  
     
     
         14 . A method according to  claim 13  wherein said transition metal complex comprises ruthenium.  
     
     
         15 . A method according to  claim 13  wherein said transition metal complex comprises iron.  
     
     
         16 . A method according to  claim 13  wherein said transition metal complex comprises cobalt.