Determination of urinary 3-methylhistidine by high-performance liquid chromatography with o-phthaldialdehyde precolumn derivatization.

A high-performance liquid chromatographic method to measure the concentration of 3-methylhistidine in human urine with o-phthaldialdehyde precolumn derivatization is described. A clear separation of the 3-methylhistidine derivative from other derivatives in urine was achieved within 25 min. The linearity, recovery and coefficients of variation were determined. The method was successfully applied to clinical assays and used for diagnostic purposes.