LC-MS/MS method for the quantification of myo- and chiro-inositol as the urinary biomarkers of insulin resistance in human urine.

A simple LC-MS/MS method has been developed and validated for the quantification of endogenous myo- and chiro-inositol in human urine. myo- and chiro-Inositol were completely resolved from other carbohydrates and there were no interference peaks in human urine. The correlation coefficient (n = 3) was greater than 0.9991 over the range 0.05-25.0 µg/mL with the weighted (1/C²) least square method. Precision (%RSD) and accuracy (%RE) were 0-10.0% and 0-6.0% for the intra-day assay (n = 5) and 0-14.3% and 0-10.0% for the inter-day assay (n = 5). myo- and chiro-Inositol have been shown to be stable in human urine stored at room temperature and for three freeze-thaw cycles.