Stopped-flow determination of creatinine in human serum and food samples

Summary

The results obtained by applying a modular stopped-flow system for the determination of creatinine by the alkaline picrate method are reported. The stopped-flow technique allows the simple and rapid determination of creatinine in human serum and food samples. The calibration graph is linear in the range 1–100 μg ml⁻¹ of creatinine and the precision is close to 3%. The method features acceptable selectivity. The initial rate is measured in only 5 s, which allows the easy application of the method to routine analyses. No pretreatment of the serum samples is required. For food samples, total creatine and creatinine have been determined in dehydrated soup and meat extract samples.