全自动酶法测定血清总和游离卡尼汀浓度及临床应用

Automated enzymatic determination for serum total and free L-carnitine and its clinical application

目的 建立自动化测定血清总和游离L 卡尼汀浓度的酶分光光度法 (CAT BTND)。方法 对卡尼汀酯水解条件及 pH和L 卡尼汀乙酰基转移酶浓度等反应条件作最佳化研究 ,同时对该法进行方法学评估 ,并用该法测定了 119名正常人的血清样本。结果 该法最低检出限为 4 81μmol/L ,线性范围可达 150 μmol/L(r =0 999)。批内和批间的平均CV分别为游离卡尼汀 5 52 %和5 90 % ,辛酯卡尼汀为 5 78%和 6 14 %。平均回收率为 98 5%和 98 4%。在胆红素≤ 12 0 μmol/L ,血红蛋白≤ 7g/L和抗坏血酸≤ 50 0 μmol/L的情况下 ,对测定结果无显著性影响。正常参考范围 :成人 :男 (3 2名 )总卡尼汀 (48 5± 17 7) μmol/L ,游离卡尼汀 (3 9 2± 14 2 ) μmol/L ,卡尼汀酯 (9 3±5 3 ) μmol/L ;女 (3 1名 )总卡尼汀 (42 7± 17 3 ) μmol/L ,游离卡尼汀 (3 2 4± 18 0 ) μmol/L ,卡尼汀酯(10 5± 5 5) μmol/L。儿童 (年龄 9～ 12岁 ) :男 (3 1名 )总卡尼汀 (57 3± 19 3 ) μmol/L ,游离卡尼汀(45 1± 14 4) μmol/L ,卡尼汀酯 (12 3± 10 4) μmol/L ;女 (2 5名 )总卡尼汀 (59 4± 15 7) μmol/L ,游离卡尼汀 (46 6± 12 6) μmol/L ,卡尼汀酯 (12 8± 7 8) μmol/L。 结论 该法正确快速 ,可作为L

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 μmol/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 μmol/L),hemoglobin(≤7 g/L),and ascorbate(≤500 μmol/L).Total and free carnitine and acylcarnitine reference range: adults (48 5±17 7) μmol/L , (39 2±14 2) μmol/L and (9 3±5 3) μmol/L(male, n =32),(42 7±17 3) μmol/L, (32 4±18 0) μmol/L and (10 5±5 5) μmol/L respectively(female, n =31).Children (age between 9～12 years old) (57 3±19 3) μmol/L , (45 1±14 4) μmol/L and (12 3±10 4) μmol/L(male, n =31), (59 4±15 7) μmol/L, (46 6±12 6) μmol/L and (12 8±7 8) μmol/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.