DEXTRAN SULFATE

All chemical precipitation methods are not equal. Typically, polyanions such as heparin, dextran sulfate, and sodium phosphotungstate are used with a divalent cation, such as magnesium, manganese, or calcium. Polyanions interact with arginine and other positively charged residues on apolipoproteins, while cations help the polyanion–lipoprotein complexes form via interaction with phospholipids. The dextran sulfate magnesium chloride precipitation method using dextran sulfate with an approximate molecular weight of 50,000, optimized to minimize HDL loss and maximize apo B-containing lipoprotein precipitation, has been credentialed as an AACC Selected Method and is the most popular precipitation method in the US. Once precipitation is complete, the cholesterol measured in the supernatant is specifically HDL cholesterol. This is an important advantage, as assays for total cholesterol are better standardized and more accurate than homogeneous HDL cholesterol assays.

The CDC reference method was the accuracy target for many influential population studies from which NCEP risk estimates and cut points were derived. However, the reference method is technically demanding and requires a 5 mL sample and an ultracentrifuge, which precludes its use as a routine reference method. The CDC and CRMLN laboratories have therefore developed and validated an alternative designated comparison method (DCM) based on precipitation with dextran sulfate and magnesium.

Please call 1-877-SUN-DIAG (786-3424) or email [email protected] for bulk ordering information