Acridinium ester labels having hydrophilic modifiers

Acridinium ester conjugates of hydrophilic modifiers with the following structure:

• wherein,
• R1 is alkyl, alkyenyl, alkynyl, aryl, sulfoethyl, sulfopropyl, sulfobutyl, or aralkyl having up to 24 carbons and up to 20 heteroatoms selected from the group consisting of nitrogen, oxygen, phosphorus and sulfur;
• R2, R3, R5, R7 are hydrogen, amino, hydroxyl, halide, nitro, —CN, SO3H, —SCN, —OR, NHCOR, —COR, —COOR, or —CONHR, wherein R is alkyl, alkenyl, alkynyl, aryl, aralkyl, having up to 24 carbons and up to 20 heteroatoms selected from the group consisting of nitrogen, oxygen, phosphorus and sulfur;
• R4 and R8 are alkyl, alkenyl, alkynyl, aralkyl or alkoxyl having up to 8 carbons;
• R6═R—L—S—R10, wherein R6 has greater than 5 heteroatoms and is alternatively attached on a position of the phenoxy ring which is meta to the ester linkage such that R5 or R7 is attached para to the ester linkage;
• R is optionally alkyl, alkenyl, alkynyl, aryl, aralkyl, having up to 24 carbons and up to 20 heteroatoms selected from the group consisting of nitrogen, oxygen, phosphorus and sulfur;
• L is selected from the group consisting of ether, thioether, amide, ester and carbamate;
• S is selected from the group consisting of polyethylene glycol varying from 280 to 5000 molecular weight and the following structures:
• and R10 is an electrophile, a leaving group, or a nucleophile.

A method for improving the hydrophilic properties of a conjugate having the general structure A—B—C, wherein,

• A is an analyte;
• B is a hydrophilic modifier selected from the group consisting of polyethylene glycol having a molecular weight of about 280-5000, or a polyionic spacer derived from a polyamine where the internal, but not necessarily all the amines have been modified by hydrophilic molecules;
• and
• C is a chemiluminescent acridinium compound containing a phenyl moiety with an ester linkage, comprising conjugating and introducing the hydrophilic modifier onto the phenyl moiety in a position meta or para to the ester linkage to improve the hydrophilic properties.

A method for improving the hydrophilic properties of acridinium ester conjugates with the following structure:

• wherein
• R1 is alkyl, alkyenyl, alkynyl, aryl, sulfoethyl, sulfopropyl, sulfobutyl, or aralkyl having up to 24 carbons and up to 20 heteroatoms selected from the group consisting of nitrogen, oxygen, phosphorus and sulfur;
• R2, R3, R5, R7 are hydrogen, amino, hydroxyl, halide, nitro, —CN, SO3H, —SCN, —OR, NHCOR, —COR, —COOR, or —CONHR, wherein R is alkyl, alkenyl, alkynyl, aryl, aralkyl, having up to 24 carbons and up to 20 heteroatoms selected from the group consisting of nitrogen, oxygen, phosphorus and sulfur;
• R4 and R8 are alkyl, alkenyl, alkynyl, aralkyl or alkoxyl having up to 8 carbons;
• R6═R—L—S—R10, wherein R6 has greater than 5 heteroatoms and is alternatively attached on a position of the phenoxy ring which is meta to the ester linkage such that R5 or R7 is attached para to the ester linkage;
• R is optionally alkyl, alkenyl, alkynyl, aryl, aralkyl, having up to 24 carbons and up to 20 heteroatoms selected from the group consisting of nitrogen, oxygen, phosphorus and sulfur;
• L is selected from the group consisting of ether, thioether, amide, ester and carbamate;
• S is selected from the group consisting of polyethylene glycol varying from 280 to 5000 molecular weight and the following structures:
• and R10 is an electrophile, a leaving group, or a nucleophile, said method comprising conjugating and introducing S onto the phenoxy ring in a position meta or para to the ester linkage to improve the hydrophilic properties.