Analyses with the KODAK-Ektachem. Accuracy control using reference method values and the influence of protein...

Area of Science:

• Clinical Chemistry
• Analytical Toxicology
• Biomedical Diagnostics

Background:

• The Ektachem 700 is a widely used analytical system in clinical laboratories.
• Evaluating the reliability of common assays is crucial for accurate patient diagnosis and treatment.
• Protein concentration can potentially interfere with various biochemical assays.

Purpose of the Study:

• To assess the accuracy and reliability of the Ektachem 700 for determining common clinical chemistry substrates.
• To investigate the influence of varying protein concentrations on assay performance.
• To compare Ektachem 700 results with established reference methods.

Main Methods:

• Accuracy was evaluated by comparing Ektachem 700 results with reference method values.
• Systematic investigation of protein concentration effects using ultracentrifugation-derived sera.
• Assays evaluated included bilirubin, cholesterol, creatinine, glucose, protein, total glycerol, urea, and uric acid.

Main Results:

• Bilirubin and cholesterol assays showed good agreement with reference methods, unaffected by protein concentration.
• Creatinine, glucose, and uric acid assays demonstrated acceptable accuracy but showed positive bias at high protein levels.
• Total glycerol and urea assays exhibited significant deviations in control sera, with high protein affecting glycerol results.

Conclusions:

• The Ektachem 700 generally provides reliable results for common substrates, meeting guideline deviations.
• High protein concentrations can introduce significant bias in specific assays (creatinine, glucose, glycerol, uric acid).
• Further validation is recommended for assays showing discrepancies, especially in samples with high protein content.