Walsh R L, Coles M E
Clin Chem. 1980 Mar;26(3):496-8.
We evaluated 10 microfilters for their ability to filter diluted sera without removing immunoglobulins (Ig) G, A, and M, albumin, and transferrin. In general, filters containing cellulose nitrate remove IgG from solution, the amount adsorbed being proportional to the IgG concentration in the solution. With some sera we noted IgA and IgM adsorption to cellulose-nitrate-containing filters, but there was no significant adsorption of albumin or transferrin to any of the filters. We also found that cellulose-nitrate filters adsorbed IgG from antiserum, with consequent loss of titre as seen in a nephelometric assay. Adsorption of IgG was not seen if the filters were prewashed with polyethylene glycol or if the antisera contained polyethylene glycol. With a sufficiently large antibody excess in the nephelometric assay, this loss of titre through filtration becomes undetectable.
我们评估了10种微滤器过滤稀释血清的能力，同时确保不除去免疫球蛋白（Ig）G、A和M、白蛋白以及转铁蛋白。一般来说，含有硝酸纤维素的滤器会从溶液中去除IgG，吸附量与溶液中的IgG浓度成正比。对于某些血清，我们注意到IgA和IgM会吸附到含硝酸纤维素的滤器上，但白蛋白或转铁蛋白对任何滤器均无明显吸附。我们还发现硝酸纤维素滤器会从抗血清中吸附IgG，如在比浊法测定中所见，随之会出现效价降低的情况。如果滤器用聚乙二醇预洗，或者抗血清中含有聚乙二醇，则不会出现IgG的吸附。在比浊法测定中，当抗体过量足够大时，通过过滤导致的效价降低就无法检测到了。
