偶氮胂Ⅲ测定血清镁

Determination of magnesium in serum with arsenazo Ⅲ reagents

目的 :建立简便、灵敏的偶氮胂Ⅲ (ArsenanoⅢ )血清镁测定法。方法 :在碱性条件下 ,用EGTA消除钙的干扰 ,偶氮胂Ⅲ与镁离子形成蓝紫色络合物 ,以分光光度法测定血清镁。结果 :偶氮胂Ⅲ -镁反应液的最大吸收峰为 6 15nm ,反应最适pH8 8,偶氮胂Ⅲ最适浓度为 15 0umol/L ,EGTA加入量为 2 0 0umol/L。本法批内CV及批间CV(n =2 0 )分别为 1 70～ 2 10 %、2 17～ 2 5 7%。平均回收率为 99 3% ,线性 0～ 3 0mmol/L。胆红素 (5 0 0umol/L以内 ) ,血红蛋白 (7g/L)。脂肪乳剂Interlipid(4g/L)对测定无干扰。该法与MTB法对照 ,结果无显著差异。 (P >0 0 5 )。结论 :偶氮胂Ⅲ测定血清镁简便、快速、灵敏、可靠 。

Objective: To establish a colormetric method for measuring magnesium in serum by ArsenazoⅢ.Methods: In the alkline medium,calcium has been selectively masking by EGTA,while Magnesium reacts with ArsenazoⅢ to form a compound.The color insensity of the compound was propotional to the concentration of magnesium in serum.Results: ArsenazoⅢ magnesium compound compound absorbs length with a peak at 615nm, under the optium pH,Arsenazo and EGTA concentration in the reagents.Intra-assay precision were 1.70 to 2.10% and interassay precision were 2.17～2.57%.The recoveries ranged from 98.8～101.5%. No interference were observed for bilirubin(500umol/L), hemoglobin(7g/L) and Intralipid (4g/L).The measurement range was 0～3mmol/L.The results showed no difference ArsenazoⅢ and MTB method.Conclusions: This method was simple,rapid,sensitive and applied to manual procedure or automatic analysis.