HemoCue: evaluation of a portable photometric system for determining glucose in whole blood

We assessed the HemoCue system for measuring glucose in 5 microL of whole blood. A glucose dehydrogenase-based reaction is used with dried reagents contained in disposable microcuvettes, which are filled with blood by capillary action. Automated hexokinase and YSI 23AM glucose analyzer methods were used for comparison. Overall imprecision (CV) was better than 4.5%, with no significant differences in results between three different HemoCue photometers and four batches of microcuvettes. Regression slopes (+/- SE) were 0.947 (0.011) with the YSI and 0.966 (0.015) with the hexokinase method. Analytical recovery of added glucose was 101-106%, and the system functioned with hematocrits up to 0.65. Bilirubin up to 453 mumol/L did not interfere, but high concentrations of endogenous (greater than 3 mmol/L) and exogenous triglycerides gave positive interference. The system proved stable and robust under a wide range of storage and handling conditions; performance was impaired only at high ambient temperature (37 degrees C). We conclude that the HemoCue system should prove useful for glucose measurement; further testing outside the laboratory is warranted.