Novel chemistry used in biosensors

Abstract

The invention relates to novel compositions of disubstituted bipyridyl osmium complexes useful for the synthesis of labeled proteins, nucleic acids, and for the modification of electrodes.

1 . A compound of chemical formula R 1 ,R 2 -bpy-Os(CN) 4   
       
         
           
           
               
               
           
         
         wherein R 1  and R 2  may be the same or different and are chosen from the group consisting of CH 3 , CH 3 (CH 2 ) m , and NH 2 (CH 2 ) n  wherein m and n are independently chosen from the group consisting of 0, 1, 2, 3, 4, 5, and 6. 
       
     
     
         2 - 3 . (canceled) 
     
     
         4 . A compound of formula R 1 ,R 2 -bpy-Os(CN) 4   
       
         
           
           
               
               
           
         
       
       wherein R 1  and R 2  are independently substituted alkyl groups wherein the substituents are chosen from the group consisting of an electrophile and a nucleophile. 
     
     
         5 - 25 . (canceled) 
     
     
         26 . A method of detecting a target enzyme comprising:
 a) contacting a sample with a composition comprising an electrode comprising:
 i) an electroactive moiety (EAM) comprising a compound of  claim 1  with a first E 0 ; 
 ii) a capture ligand; 
   under conditions whereby said target enzyme, if present, alters said capture ligand such that said EAM has a second E 0 ; and   b) measuring said second E 0 .   
     
     
         27 . The method according to  claim 26 , wherein said composition comprises a support comprising a plurality of electrodes each comprising:
 i) an electroactive moiety (EAM) comprising a compound of  claim 1  with a first E 04) ;   ii) a capture ligand.   
     
     
         28 . A method of detecting a target enzyme comprising:
 a) contacting a sample with a composition comprising a REAMC comprising:
 i) an electroactive moiety (EAM) comprising a compound of  claim 1  with a first E 0 ; 
 ii) a capture ligand; 
   under conditions whereby said target enzyme, if present, alters said capture ligand such that said EAM has a second E 0 ; and   b) measuring said second E 0 .   
     
     
         29 . A composition comprising an electrode comprising:
 a) a first species comprising a functional group; and   b) an electroactive complex (EAM), said EAM comprising a compound of  claim 1 .   
     
     
         30 . The composition according to  claim 29 , wherein said functional group is a maleimide group. 
     
     
         31 . A method of making a biosensor comprising:
 a) providing an electrode comprising:
 i) a first species comprising a first functional group; and 
 ii) an electroactive complex (EAM), said EAM comprising a compound of  claim 1 ; 
   c) contacting said electrode with a biomolecule comprising a second functional group to form a covalent bond between said first species and said biomolecule.   
     
     
         32 . The method according to  claim 31 , wherein said first functional group is selected from the group consisting of moieties comprising a maleimide, imidoester, N-hydroxysuccinimidyl, alkyl halide, aryl halide, alpha-haloacyl and pryidyl disulfide. 
     
     
         33 . The method according to  claim 31 , wherein said first functional group comprises a maleimide and said biomolecule is a protein comprising a cysteine amino acid. 
     
     
         34 . The method according to  claim 33 , wherein said protein is a peptide. 
     
     
         35 . A compound having the formula:
   Anchor-Spacer 1-EAM-(Spacer 2) n -CL  (I)
   
       wherein said anchor comprises a cyclic-disulfide group,
 EAM is a compound of  claim 1 , 
 CL is a capture ligand, 
 Spacer 1 is a SAM forming species, and 
 n=0 or 1. 
 
     
     
         36 . The compound according to  claim 35 , wherein said cyclic-disulfide group comprises pyridyl-oligophenylethylnyl-[1,2,5]-dithiazepane. 
     
     
         37 . A composition comprising an electrode comprising a self-assembled monolayer (SAM), wherein said SAM comprises a compound having the formula:
   Anchor-Spacer 1-EAM-Spacer 2-CL  (II),
   
       wherein said anchor is linked to said electrode group through a disulfide group,
 EAM is a compound of  claim 1 , 
 CL is a capture ligand, 
 Spacer 1 is either insulating or conducting, and 
 Spacer 2 is optional. 
 
     
     
         38 . A method, comprising:
 a) providing a compound having the formula:
   Anchor-Spacer 1-EAM-(Spacer 2) n -CL  (I),
 
   
       wherein said anchor comprises a cyclic-disulfide group,
 EAM is a compound of  claim 1 , 
 CL is a capture ligand, 
 Spacer 1 is either insulating or conduction, and 
 n=0 or 1; and 
 contacting said compound to an electrode by opening said cyclic disulfide to form an attachment of said anchor to said electrode. 
 
     
     
         39 . The method according to  claim 38 , wherein said electrode further comprises a self-assembled monolayer (SAM). 
     
     
         40 . A method of detecting a target analyte in a test sample, comprising:
 b) providing an electrode comprises a compound having the formula:
   Anchor-Spacer 1-EAM-(Spacer 2) n -CL  (I),
 
   
       wherein said anchor comprises a cyclic-disulfide group,
 EAM is a compound of  claim 1 , 
 CL is a capture ligand, 
 Spacer 1 is either insulating or conduction, and 
 n=0 or 1; and 
 contacting said electrode with said test sample; and 
 determining the presence of said target analyte by measuring the reorganization energy of said EAM.