Gaffin S L
Prog Clin Biol Res. 1979;29:221-7.
LAL would not form a clot when mixed with a viscous, opaque parenteral preparation of iron dextran spiked with endotoxin. However, recoverable precipitate could be obtained by diluting the LAL iron dextran mixture with PBS and centrifuging. Although the pellet so formed was red colored the protein present could be quantitated by dissolving it in a Coomassie Blue stain solution. The very rapid change in color from reddish black to deep blue was measured quantitatively in a spectrophotometer and was sigmoidally related to the amount of endotoxin used to spike the iron dextran. This method is suggested to be generally useful to measure quantitatively endotoxin concentrations too low to form a clot with LAL but high enough to precipitate recoverable protein from LAL.
当鲎试剂（LAL）与掺有内毒素的黏稠、不透明右旋糖酐铁肠胃外制剂混合时，不会形成凝块。然而，通过用磷酸盐缓冲盐水（PBS）稀释LAL与右旋糖酐铁的混合物并离心，可以获得可回收的沉淀物。虽然如此形成的沉淀呈红色，但其中存在的蛋白质可以通过将其溶解在考马斯亮蓝染色溶液中进行定量。在分光光度计中对从红黑色到深蓝色的非常快速的颜色变化进行了定量测量，并且该变化与用于掺入微右旋糖酐铁的内毒素量呈S形相关。建议该方法通常可用于定量测量浓度过低而无法与LAL形成凝块但又高到足以从LAL中沉淀出可回收蛋白质的内毒素浓度。
