In the kinetic Jaffe method for quantifying serum creatinine, which filtrate is used in the analysis?

In the kinetic Jaffe method for quantifying serum creatinine, which filtrate is used in the analysis?

• A. Serum sample used directly
• B. Folin-Wu filtrate
• C. Somogyi-Nelson filtrate
• D. Trichloroacetic acid filtrate

Answer: (A)

In the kinetic Jaffe method, the test relies on the rate at which creatinine reacts with alkaline picrate to form a colored complex. This kinetic measurement is performed by mixing the serum with the reagent and monitoring the change in absorbance over a short interval. Because this approach follows the reaction in real time, there is no need to separate creatinine or remove proteins through filtration or deproteinization steps. Therefore, the serum sample itself is used directly in the analysis. The other filtrates mentioned come from older or alternative procedures that involve deproteinizing or filtering the sample to remove interfering substances before measurement. Those steps are not part of the kinetic Jaffe approach, which is designed to quantify creatinine directly from the serum.

In the kinetic Jaffe method, the test relies on the rate at which creatinine reacts with alkaline picrate to form a colored complex. This kinetic measurement is performed by mixing the serum with the reagent and monitoring the change in absorbance over a short interval. Because this approach follows the reaction in real time, there is no need to separate creatinine or remove proteins through filtration or deproteinization steps. Therefore, the serum sample itself is used directly in the analysis.

The other filtrates mentioned come from older or alternative procedures that involve deproteinizing or filtering the sample to remove interfering substances before measurement. Those steps are not part of the kinetic Jaffe approach, which is designed to quantify creatinine directly from the serum.