血清氯化物酶法测定

Direct enzymatic determination of chloride in serum

目的 建立血清氯化物的α 淀粉酶及其底物 2 氯 4 硝基苯 α D 麦芽三糖苷 (CNP G3)直接测定方法。方法 根据氯离子是α 淀粉酶的激动剂原理建立氯化物测定方法 ,并做方法学评价。结果 测定结果的平均偏差率为 0 4 6 % ;线性范围 5 0～1 5 0mmol/L ;平均回收率为 1 0 0 6 2 % ;批内CV <1 2 4 % ,日间CV <1 86 % ,总CV1 4 5 %～ 2 2 4 % ;加入高浓度的维生素C、葡萄糖、蔗糖、果糖、α 淀粉酶、三酰甘油、血红蛋白、胆红素、钙离子、溴离子、碘离子、氟离子、硫氰酸钾、对硝基酚、叠氮钠和硫酸铵均未显示干扰。与硫氰酸汞比色法 (MTC) ( x±s)比较 :MTC法 (X) :(95 6 6± 1 4 .4 5 )mmol/L ,酶法 (Y) :(95 6 2± 1 4 .93)mmol/L ,t=0 .0 78,P >0 5 ,Y =1 .0 1 6X - 1 .5 87,r=0 .984 ,n =93,P <0 .0 0 1 ;与离子选择电极法 (ISE) ( x±s)比较 :ISE法 (X) :(99.0 0±1 3.1 1 )mmol/L ,本法 (Y) (98.6 1± 1 2 .70 )mmol/L ,t=0 .1 4 0 ,P >0 .5 ,Y =0 .96 2X +3.375 ,r=0 .993,n =4 4 ,P <0 .0 0 1。溶解的工作试剂 (R1、R2 ) 2～ 8℃冷藏至少可以稳定 1 4天。结论 该方法测定成本低 ,准确、精密、线性范围宽 ,稳定性好 ,在抗卤族元素溴、碘及硫氰酸等阴离子的干扰方面 。

Objective To set up a new direct measuring method for serum chloride by using α amylase and its substrate 2 chloro 4 nitrophenyl alpha maltotrioside.Methods The principle of the proposed method was according to chloride being a stimulator forα amylase.Results The mean bias between assay values and target values in quality control sera was 0.46%.The linearity range was from 50 mmol/L to 150 mmol/L.The mean recovery rate was 100.62%.The coefficient of variation ( CV ) of within runs was less than 1.24%.The CV of day to day was less than 1.86% and total CV was from 1.45% to 2.24%.Adding of high concentration of Vitamin C,glucose,sucrose,fructose,α amylase,triglyceride,hemoglobin,bilirubin,calcium,bromine,iodine,fluorine,potassium thiocyanate,paranitrophenol,sodium azide or ammonium sulfate into samples did not interfere chloride measurement by the proposed method.By comparison the results of mercuric thiocyanate colorimetry (MTC, X ) and the proposed method ( Y ) were 95.66±14.45 mmol/L and 95.62±14.93 mmol/L ( ± s ), t =0.078, P <0.5; Y = 1.016x 1.587, r =0.984, n =93, P <0.001;The results of ion selective electrode (ISE) method ( X ) and the proposed method ( Y ) were 99.00 ±13.11 mmol/L vs 98.61±12.70 mmol/L, t =0.140, P <0.5, Y =0.962 X +3.375, r =0.993, n =44, P <0.001.Stability of the dissolved working reagents was at least two weeks at 2~8℃refrigerator.Conclusion The established method was much better than other methods for measuring chloride because of cost saving ,accuracy,precision,wide linearity range,good specificity and stability and its resisting interference from haloid elements such as bromine and iodine and thiocynate etc.