Enzymatic measurement of serum glycerol using a COBAS-BIO centrifugal analyzer

An enzymatic method for the measurement of glycerol using glycerol kinase coupled to pyruvate kinase and lactate dehydrogenase was adapted to a COBAS-BIO centrifugal analyzer. Routine standardization is not required under the optimized conditions since the calculation factor derived from the measurement of pure glycerol standard was found to be identical to the theoretical value. Excellent correlation between the method and the DuPont ACA triglyceride method was obtained. The coefficients of variation for within-run and day-to-day precision were less than 4%. Only 2 microL of serum is required, making this an excellent means for monitoring therapeutic glycerol administration in premature infants with hydrocephalus. The method has the sensitivity to measure glycerol concentrations as low as 0.1 mmol/L. This, together with the rapid analysis time (28 specimens in 10 min), makes it suitable for the correction of glycerol interference in the measurement of serum triglyceride.