Abstract Novel biological assay method for determining the presence of a specific organic material by employing a modified enzyme for amplification. By employing receptors specific for one or a group of materials (hereinafter referred to as "ligands") and binding an enzyme to the ligand or ligand counterfeit to provide an "enzyme-bound-ligand", an extremely sensitive method is provided for assaying for ligands. The receptor when bound to the enzyme-bound-ligand substantially inhibits enzymatic activity, providing for different catalytic efficiencies of enzyme-bound-ligand and enzyme-bound-ligand combined with receptor. The receptor, ligand and enzyme-bound-ligand are combined in an arbitrary order and the effect of the presence of ligand on enzymatic activity determined. Various protocols may be used for assaying for enzymatic activity and relating the result to the amount of ligand present.
An enzyme-bound-ligand of the formula: ##STR61## wherein: any one of the W groups can be --X* or an H of any of the W groups may be replaced by --X*, wherein --X* is a bond or a linking group of from 1 to 8 carbon atoms, and from 1 to 4 heteroatoms; A* is an enzyme bonded at other than its reactive site, having n ligands wherein n is in the range of 1 to the molecular weight of A* divided by 2,000; W 60 is hydrogen or hydroxyl; W 61 is hydrogen, methyl, or hydroxyl; W 62 and W 63 are hydrogen or hydroxyl; with the proviso that at least one of W 60-63 is hydroxy, or two of W 60-63 are taken together to form oxo; W 64 is hydrogen, or two W 64 's are taken together to form a double bond; W 65 is methyl; and W 66 is hydrogen.
Claim 2
Dependent Claim
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An enzyme-bound-ligand of the formula: ##STR61## wherein: any one of the W groups can be --X* or an H of any of the W groups may be replaced by --X*, wherein --X* is a bond or a linking group of from 1 to 8 carbon atoms, and from 1 to 4 heteroatoms; A* is an enzyme bonded at other than its reactive site, having n ligands wherein n is in the range of 1 to the molecular weight of A* divided by 2,000; W 60 is hydrogen or hydroxyl; W 61 is hydrogen, methyl, or hydroxyl; W 62 and W 63 are hydrogen or hydroxyl; with the proviso that at least one of W 60-63 is hydroxy, or two of W 60-63 are taken together to form oxo; W 64 is hydrogen, or two W 64 's are taken together to form a double bond; W 65 is methyl; and W 66 is hydrogen.
Claim 3
Dependent Claim
10 words
An enzyme-bound-ligand according to claim 1, which is an oxidoreductase.
Claim 4
Dependent Claim
10 words
An enzyme-bound-ligand according to claim 1, which is a hydrolase.
Claim 5
Dependent Claim
13 words
An enzyme-bound-ligand according to claim 1, which is testosterone-3-carboxymethyloxime conjugate to malate dehydrogenase.
Claim 6
Dependent Claim
14 words
An enzyme-bound-ligand according to claim 1, which is testosterone-3-carboxymethyloxime conjugate to glucose 6-phosphate dehydrogenase.