【摘要】 建立了血浆氨的靛酚蓝直接显色测定新方法 ,研究了介质酸度、显色时间、共存物质及抗凝剂等的影响。结果表明 ,以柠檬酸钠作抗凝剂 ,在pH 10 . 5～ 11 .2的磷酸盐缓冲体系中显色强度高 ,干扰小。有色化合物最大吸收波长位于 6 30nm ,表观摩尔吸光系数为 2 . 4 8× 10 .4L·mol-1·cm-1。血浆氨浓度在 0～ 15. 0 0μmol·L-1范围线性关系良好 (r =0 .9999) ,检测下限为 1 7μmol·L-1,相对标准偏差RSD为 1 13% (n =11) ,回收率为 93. 6 %～ 10. 1 6 % ,平均回收率 97 .0 %。用本法测定 4 3例正常人和 97例各型肝病患者血浆氨含量均获得满意结果。更多还原

【Abstract】 A new method for direct determination of ammonia in plasmas with indophenol reagent is described. It is shown that using sodium citrate as anticoagulant in phosphate buffer within pH 10.5-11.2, indophenol reagent reacts sensitively with ammonia in the plasmas to form a stable blue compound with a maximum absorption at 630 nm with low interference. The apparent molor absorptivity is 2.48×104 L·mol -1·cm -1, and the linear range 0-1 500 μmol·L -1 (r=0.999 9) with a detection limit of 1.7 μmol·L -1. The relative standard deviation is 1.13%(n=11) and the recoveries are in the range of 93.6%-101.6% with an average recovery of 97.0%. The proposed method has been applied to detect ammonia in the plasmas from 43 healthy persons and 97 patients who suffered from liver diseases with satisfactory results.更多还原