Abstract
The analytical performance of a new, whole blood glucose and lactate electrode system (EML™ 105 analyser, Radiometer Medical A/S, Copenhagen, Denmark) was evaluated. Between-day coefficients of variation were ≤1·9% and ≤3·1% for glucose and lactate, respectively. Recoveries of glucose were 100 ± 10% using either aqueous or protein-based standards. Recoveries of lactate depended on the matrix, being underestimated in aqueous standards (≈ −10%) and 95–100% in standards containing 40 g/L albumin at lactate concentrations of 15 and 30 mmoI/L. However, recoveries were high (up to 180%) at low lactate concentrations in protein-based standards. Carry-over, investigated according to National Clinical Chemistry Laboratory Standards EP10-T2, was negligible (α = 0·01). Glucose and lactate biosensors equipped with new membranes were linear up to 60 and 30 mmol/L, respectively. However, linearity fell upon daily use with increasing membrane lifetime. We conclude that the Radiometer metabolite biosensor results are reproducible and do not suffer from specimen-related carry-over. However, lactate recovery depends on the protein content and the lactate concentration.