Patent ID: 8663946

Claim:
A method for detecting one or more folates selected from a group consisting of dihydrofolate (DHF), tetrahydrofolate (THF), 5-methyltetrahydrofolate (5-CH 3 -THF) and 10-formyltetrahydrofolate (10-CHO-THF), comprising the following steps: (a) mixing a sample and an extraction buffer to form a mixture, boiling the mixture and cooling to an ambient temperature, and separating a supernatant from the mixture by centrifugation; (b) adding a recombinant γ-glutamyl hydrolase (GGH), reduced nicotinamide adenine dinucleoside phosphate (NADPH), and one or more folate conversion enzymes selected from a group consisting of dihydrofolate reductase (DHFR), 10-formyltetrahydrofolate dehydrogenase (FDH), and a combination of serine hydroxymethyl-transferase (SHMT) and methylene-tetrahydrofolate dehydrogenase (MTD) to the supernatant to drive a reaction; (c) stopping the reaction; and (d) analyzing the reaction mixture by high performance liquid chromatography to quantify the one or more folates.