Cohn J R, Buckley C E, Connell C D
Diagn Immunol. 1984;2(3):175-80.
Serum samples were drawn from 14 healthy volunteers after an overnight fast and again after a meal. Each sample was divided into two aliquots. One aliquot was centrifuged at 20,000 rpm for 20 min, and a portion from the middle of the tube was removed by puncturing the tube's side. All samples were then added to cuvettes containing 0.14 M NaCl alone or 1, 2, 3, or 4% polyethylene glycol in 0.15 M KCl. The light scattering of each tube was measured. The centrifuged samples scattered 58% less light than the uncentrifuged controls. The range of values obtained with the centrifuged samples was also smaller as reflected in the standard deviation of the means obtained at each polyethylene glycol concentration. The coefficient of variation for replicate samples ranged from 0 to 16.6% (mean 5.8%), even when samples were processed differently. Storage at -70 degrees C significantly increased light scattering compared to baseline values. Serum samples were drawn from 44 patients with diseases that have been associated with immune complexes. Nephelometry selectively identified some groups of patients as abnormal. We conclude that preparative ultracentrifugation removes much of the background light scattering of serum samples, including that due to lipid, under conditions that do not sediment out immune complexes. Because it measures a physical property of immune complexes, this assay may provide information that is not available from biological receptor-based assays.
在空腹过夜后和进食后分别从14名健康志愿者身上采集血清样本。每个样本分成两份。一份以20,000转/分钟的速度离心20分钟，然后通过刺穿试管侧面从试管中部取出一部分。然后将所有样本添加到含有单独0.14M NaCl或含有1%、2%、3%或4%聚乙二醇的0.15M KCl的比色皿中。测量每个试管的光散射。离心后的样本比未离心的对照样本散射的光少58%。离心样本获得的值范围也较小，这在每个聚乙二醇浓度下获得的平均值的标准偏差中得到反映。重复样本的变异系数范围为0至16.6%（平均5.8%），即使样本处理方式不同。与基线值相比，在-70℃下储存显著增加了光散射。从44名患有与免疫复合物相关疾病的患者身上采集血清样本。散射比浊法选择性地将一些患者组识别为异常。我们得出结论，在不使免疫复合物沉淀的条件下，制备性超速离心去除了血清样本中大部分的背景光散射，包括由于脂质引起的光散射。由于该检测方法测量免疫复合物的物理特性，它可能提供基于生物受体的检测方法无法获得的信息。
