Comparison of three assay procedures for gentamicin determination

Area of Science:

• Clinical Chemistry
• Pharmacology
• Analytical Biochemistry

Background:

• Accurate measurement of gentamicin levels is crucial for therapeutic drug monitoring.
• Enzyme multiplied immunoassay technique (EMIT) and radioimmunoassay (RIA) are established methods for gentamicin quantification.
• Novel, cost-effective methods are sought to improve laboratory efficiency.

Purpose of the Study:

• To compare the analytical performance of a latex agglutination (LA) method with EMIT and RIA for serum gentamicin level determination.
• To evaluate the accuracy, precision, throughput, and cost-effectiveness of the LA method.

Main Methods:

• Serum samples (n=50) were analyzed for gentamicin concentrations using EMIT, RIA, and a latex agglutination procedure.
• Assay precision and recovery were assessed for the LA method.
• Throughput and cost analyses were conducted for all three methods.

Main Results:

• Significant differences in gentamicin concentrations were observed between the LA method and both EMIT and RIA.
• The LA method demonstrated faster throughput and lower costs compared to EMIT and RIA.
• Assay precision for LA ranged from 5.21% to 15.70%, with recovery values from 83.8% to 110.0%.

Conclusions:

• While the latex agglutination method offers advantages in speed and cost, its significant analytical discrepancies render it inadequate for accurate gentamicin level measurement.
• EMIT and RIA remain more reliable methods for precise gentamicin quantification in clinical settings.