Acetaminophen assay
AssigneeSekisui Diagnostics, LLC
InventorsMichael Bulger, Jan Holinsky
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Abstract
In general, the present invention provides a reliable assay for the quantitative determination of p-aminophenol in an aqueous sample. More particularly, the present invention provides a rapid enzyme-based assay for the quantitative determination of acetaminophen in a sample. The assay employs a xylenol chromophore and a catalyst that is preferably a weak oxidizer. The assay provides reliable results in the presence or absence of N-acetylcystiene (NAC) and can therefore be used to monitor acetaminophen levels during NAC treatment. Methods and kits for determining acetaminophen concentration in an aqueous sample are also provided.
Claims25
A method for determining the concentration of acetaminophen in an aqueous sample, the method comprising the steps of:
- hydrolyzing acetaminophen to form p-aminophenol;
- oxidatively coupling the p-aminophenol to a xylenol chromophore in the presence of a suitable catalyst to form a colored product;
- and
- determining the amount of the colored product formed, the amount of the colored product formed being proportional to the amount of acetaminophen initially present in the aqueous sample,
- wherein the method is reliable in the presence or absence of therapeutic levels of N-acetylcysteine (NAC) in the aqueous sample.
An assay for determining the concentration of acetaminophen in an aqueous sample, the assay comprising the steps of:
- contacting the aqueous sample with a first reagent (R1) comprising an aryl acylamidase enzyme and a suitable diluent to form a hydrolysis solution;
- optionally, diluting the hydrolysis solution;
- incubating the hydrolysis solution to permit a hydrolysis reaction wherein the acetaminophen is converted to p-aminophenol;
- contacting the hydrolysis solution with a second reagent (R2) comprising a xylenol chromophore and a suitable diluent, to form an oxidative coupling solution;
- incubating the oxidative coupling solution to permit an oxidative coupling reaction wherein the xylenol chromophore is coupled to the p-aminophenol in the presence of a suitable catalyst to form a colored product;
- and
- determining the amount of the colored product formed, the amount of the colored product formed being proportional to the amount of acetaminophen initially present in the aqueous sample,
- wherein the assay is reliable in the presence or absence of therapeutic levels of N-acetylcysteine (NAC) in the aqueous sample.
A method for determining the concentration of p-aminophenol in an aqueous sample, the method comprising the steps of:
- oxidatively coupling the p-aminophenol to a xylenol chromophore selected from the group consisting of 2,5-dimethylphenol, 2,6-dimethylphenol and 2,3-dimethylphenol, in the presence of a catalyst to form a colored product, the catalyst being a weak oxidizer;
- and
- determining the amount of the colored product formed, the amount of the colored product formed being proportional to the amount of p-aminophenol initially present in the aqueous sample.
Dependencies are inferred from the claim text.