Development of a stable lipoprotein diluent for use in reconstituting lyophilized human serum for the preparation of clear, hyperlipidemic quality-control materials.

We describe a simple system for the preparation of a hyperlipidemic control serum. Beta- and pre-beta-lipoproteins are removed from the serum and prepared as a stable diluent; the extracted serum is then lyophilized. Upon addition of the lipoprotein diluent, which was observed to contain only liproprotein and sodium bicarbonate, the serum reconstitutes rapidly, usually within 5 min. By a suitable adjustment of the lipoprotein concentration in the diluent, a hyperlipidemic control serum may be produced with desired concentrations of lipids. Because the lipoproteins are not included in the destructive lyophilization step, the resulting product has remarkable clarity, precision, and stability.