LAUSR

&NA; Several metabolites in human serum have been identified as potential cancer biomarkers for early detection. This study focuses on the LC–MS/MS method development and validation of D‐mannose in human serum. Surrogate blank serum, coupled with stable isotope D‐mannose‐13C6, as internal standard, was used for generating standard curves ranging from 1 to 50 &mgr;g/mL. Separation was achieved by an Agilent 1200 series HPLC equipped with a SUPELCOGELTM Pb, 6% Crosslinked column with HPLC water as a mobile phase at flow rate of 0.5 mL/min at 80 °C. Mass detection was performed under negative ionization electrospray. Inter‐ and intra‐day accuracy and precision were <2%. The extraction recovery and matrix effect were 104.1%–105.5% and 97.0%–100.0%, respectively. This method was successfully applied for the quantification of D‐mannose in the serum samples of 320 esophageal cancer patients and 323 healthy volunteers. We report a simple, specific and reproducible LC–MS/MS method for the quantification of D‐mannose in human serum as a potential cancer biomarker. HighlightsA validated, simple, and reproducible LC–MS/MS method for the quantification of D‐mannose in human serum.The method is suitable for clinical sample analysis.Method was validated to be accurate and precise over the concentration range of 1–50 &mgr;g/mL.Method: provides baseline separation of mannose and glucose with no interference from biological medium.Results suggest that D‐mannose levels may prove to be a useful biomarker for the screening and diagnosis of this disease.