Comparison of the Beckman Auto ICS and the Syva Autolab 6000 for determination of gentamicin levels in serum

Two fully automated drug-monitoring systems, the Syva Autolab 6000 and the Beckman Auto ICS, were compared in terms of accuracy, precision, speed of operation, and cost effectiveness in the determination of gentamicin levels in serum. Within-run and between-run precision for both systems were acceptable (coefficient of variation, 2.0 to 6.9%), and patient sample comparisons resulted in an intermethod correlation coefficient of 0.96. When reference samples (prepared to contain 1.2 to 10 micrograms of gentamicin per ml) were assayed, the Syva Autolab 6000 obtained concentrations within 8% of expected values, whereas the Beckman Auto ICS reported values up to 17% higher than target values. In a time and cost comparison, reagent costs for the Beckman system were ca. 50% less than for the Syva Autolab 6000; the Syva system, however, determined patient results two to three times faster than the Beckman Auto ICS.