Development and evaluation of a robotics-based system for glycosylated hemoglobin analysis

Abstract

Pipetting robots are ideal for automating manually intensive areas of the clinical chemistry laboratory. Glycosylated hemoglobin (GHb), which is helpful in monitoring long term glucose control in diabetics, requires extensive technologist time for analysis. Since separation of GHb is achieved on individual disposable columns, we were able to minimize technologist ‘hands on’ time required by programming a Hamilton Microlab 2200 automated pipetting Cartesian robot to complete the procedure from aspiration of blood specimen from the vacutainer tube to transfer of the separated GHb and non-GHb fractions to a microtiter plate for absorbance reading. After demonstrating that we could use unwashed red blood cells without interferences, we evaluated the system for throughput, precision, linearity, recovery and lyse method. The robotic system can analyze, in parallel, 96 specimens including patient specimens and control material in approximately 3 h. The Hamilton robotic method decreased the required technologist time relative to the manual method by 80% in ‘hands on” time and decreased the analysis time by 40%. The precision at different levels of GHb ranged from 1.6 to 3.5% within-run and from 2.7 to 3.5% day-to-day. The method correlated with the Accuflex semi-automated robot which used the identical disposable column. Automation of the GHb procedure improved throughput, precision and laboratory safety with the added benefit of reduced labor cost.