Aune S, Aasen A O, Kierulf P, Strømme J H
Acta Chir Scand Suppl. 1982;509:55-8.
Endotoxins are highly biologically active compounds found in the cell wall of Gram-negative bacteria. A method has been developed to determine endotoxins quantitatively in plasma, using Limulus lysate and a new chromogenic peptide substrate (S-2423, KabiVitrum, AB, Stockholm, Sweden). Blood samples were collected in pyrogen-free tubes (Mallinckrodt Inc., St. Louis, USA) containing heparin as anticoagulance. Platelet poor plasma was prepared by centrifugation at 1500 x g at 4 degrees C for 10 min. Standard solutions were prepared by adding E-coli endotoxin (Mallinckrodt Inc., St. Louis, USA) to plasma from normals. Limulus lysate (Pyrogent, Mallinckrodt Inc., St. Louis, USA) was incubated with samples and standards for 30 min. at 37 degrees C. The chromogenic substrate /S-2423) was then added and the mixture incubated for 3 1/2 min. The reaction was stopped with 50% acetic acid. Absorbance read against a separate plasma blank was recorded photometrically at 405 nm. The standard curve was linear in the range 0.025 to 0.200 ng/ml.
内毒素是革兰氏阴性菌细胞壁中发现的具有高度生物活性的化合物。已经开发出一种方法，使用鲎试剂和一种新的显色肽底物（S - 2423，瑞典斯德哥尔摩卡比维特伦公司）定量测定血浆中的内毒素。血液样本采集于含有肝素作为抗凝剂的无热原试管（美国密苏里州圣路易斯马林克罗德特公司）中。通过在4℃下以1500×g离心10分钟制备少血小板血浆。通过向正常人血浆中添加大肠杆菌内毒素（美国密苏里州圣路易斯马林克罗德特公司）制备标准溶液。将鲎试剂（美国密苏里州圣路易斯马林克罗德特公司的Pyrogent）与样品和标准品在37℃下孵育30分钟。然后加入显色底物/S - 2423），混合物孵育3.5分钟。用50%乙酸终止反应。在405nm处用分光光度计记录相对于单独血浆空白对照读取的吸光度。标准曲线在0.025至0.200 ng/ml范围内呈线性。
