Objective: In the present communication, development and validation of reverse phase-high performance liquid chromatography method have been carried out for estimation of oxalate content in the urine of human volunteers with recurrent kidney stone disease and healthy status.Methods: The analysis of oxalic acid has been carried out on KYA TECH HiQ Sil C18HS column using a mobile phase of methanol: 0.001 N acetic acid in water (50:50, v/v) with a flow rate of 1 ml/min and detection wavelength, 237 nm.Results: Analysis of oxalate content was carried out using single point calibration method with retention at 2.705 min with good resolution parameters. Urine sample collected from kidney stone patients and healthy volunteers over the period of 24 h were analyzed and it has been found that concentration of oxalate in healthy volunteers is less than 12 µg/ml whereas that in case of kidney stone patients is in the range of 39-151 µg/ml and this data can be utilized for further interpretations about oxalate content in healthy and kidney stone diseased volunteers. This method was validated as per united states food and drug administration (USFDA) guidelines by the study of accuracy, precision, linearity, range, selectivity, the lower limit of quantitation, extraction recovery studies and stability studies for determining oxalate content in the urine of human volunteers. As relative standard deviations of oxalate content estimated are less than 5 percent, the method can be claimed accurate, precise, sensitive and selective for determining oxalate content in the urine of human volunteers.Conclusion: The results are satisfactory, proving the effectiveness of the method for analysis of oxalate content from other biological fluids with few optimizations
