Automated enzymatic determination for serum total and free L-carnitine and its clinical application / 中华检验医学杂志

ABSTRACT

Objective To establish an automated spectrophotometic assay for serum total and free L-carnitine with enzymatic method(CAT-BTND). Methods To optimize the reaction conditions of hydrolysis,pH and L-carnitine Acetyl-transferase (CAT)concentration in the assay,to evalute the assay method and to measure the serum L-carnitine of health adults ( n =63) and children ( n =56). Results The calibration curve for L-carnitine was linear between 4 81 and 150 ?mol/L( r =0 999).The inter and intra average CV were 5 52% and 5 90% in free carnitine,5 78% and 6 14% in octanoylcarnitine.The mean recovery rate was 98 5% and 98 4% respectively.This method was free from interference by bilirubin(≤120 ?mol/L),hemoglobin(≤7 g/L),and ascorbate(≤500 ?mol/L).Total and free carnitine and acylcarnitine reference range adults (48 5?17 7) ?mol/L , (39 2?14 2) ?mol/L and (9 3?5 3) ?mol/L(male, n =32),(42 7?17 3) ?mol/L, (32 4?18 0) ?mol/L and (10 5?5 5) ?mol/L respectively(female, n =31).Children (age between 9～12 years old) (57 3?19 3) ?mol/L , (45 1?14 4) ?mol/L and (12 3?10 4) ?mol/L(male, n =31), (59 4?15 7) ?mol/L, (46 6?12 6) ?mol/L and (12 8?7 8) ?mol/L respectively(female, n =25). Conclusion The procedure is rapid,accurate and automatable,and could be used to diagnose L-carnitine deficiency,and to estimate and monitor the effect of treatments.