Patent ID: 8778688

Claim:
A method of quantifying D-serine in plasma comprising the steps of: (a) contacting a quantity of plasma with a quantity of a first acidic liquid, wherein the plasma comprises D-serine, thereby forming an acidified sample; (b) contacting the acidified sample with a quantity of a cation exchange resin, thereby separating the acidified sample into a first component and a second component, wherein the first component comprises D-serine and is retained on the resin; (c) rinsing the resin containing the retained first component with a quantity of a second acidic liquid; (d) contacting the resin with a quantity of a first basic liquid, thereby eluting from the resin D-serine and forming a D-serine eluent; (e) contacting the D-serine eluent with flavin adenine dinucleotide and a quantity of D-amino acid oxidase in the presence of a precursor to a fluorescence signal and a quantity of horse radish peroxidase; and (f) detecting the fluorescence signal.