Colorimetric, enzymatic, and liquid-chromatographic methods for serum uric acid compared

Area of Science:

• Analytical Chemistry
• Clinical Chemistry

Background:

• Serum uric acid levels are critical biomarkers in various health conditions.
• Existing methods for uric acid measurement may have limitations in accuracy and interference.

Purpose of the Study:

• To establish high-performance liquid chromatography with electrochemical detection (HPLC-ECD) as a reference method for serum uric acid.
• To evaluate the accuracy, precision, and efficiency of the developed HPLC-ECD method.

Main Methods:

• Serum samples were analyzed using HPLC with a strong anion-exchange column.
• Electrochemical detection was employed at a potential of +0.80 V vs. Ag/AgCl.
• Results were compared against phosphotungstate and uricase methods.

Main Results:

• Linearity was observed up to 1.0 g/liter with no interferences.
• Within-run and day-to-day coefficients of variation were 0.83% and 1.1%, respectively.
• Analytical recoveries averaged 100%, with high correlation coefficients (r=0.995 and r=0.999) compared to existing methods.

Conclusions:

• HPLC-ECD provides a highly accurate and selective reference method for serum uric acid quantification.
• The method demonstrates excellent precision, recovery, and minimal interference.
• The technique allows for rapid analysis (20 samples/h) without the need for deproteinization.