Abstract
We have developed a reversed phase high performance liquid chromatography for determining serum and urinary creatinine levels using 500mM phosphate buffer (pH 7.0) as a mobile phase and a BSA-ODS column (5μm, TSK: 4.6 I. D.×150mm). Retention times of creatinine (6.3min) in serum and urine samples were well correlated with the pH and concentration of phosphate buffer. Creatinine was well separated from other substances in samples under the conditions of pH 7.0 and 500mM phosphate buffer. This method also enabled the direct injection of serum and urine samples onto column. The minimum detection limit of this method was about 0.10mg/dl of creatinine. Intra-assay coefficients of variation were under 3.0 and 3.1% for serum and urine, respectivery. Recovery rates were about 90-100% for serum and urine, respectivery. Correlation of creatinine values showed r=0.988 for serum samples (n=39) between the proposed HPLC and the creatinine deiminase method, and r=0.997 for urine samples (n=43) between the HPLC and the Jaffé's method, respectivery. This proposed HPLC may be especially recommended for determination of a creatinine clearance rate.
