Albumin Uric acid Urea Phosphorus Alanine aminotransferase Alkaline phosphatase#{176} Creatine kinase Cholinesterase Triglycerides Sodium Chloride Apolipoprotein B Ceruloplasmin Albumin IgG aj-Globulin /3-Globulin /3-Lipoprotein cholesterol a-Lipoprotein cholesterol Phosphatidylethanolamine Thlycerides Cholesteryl esters

Of these six precipitation methods, I, II, and VI best minimize AA interference. Despite the greater dilution involved with the unbuffered PEG method, the degree of interference is similar to that found with methods III and IV. AA is known to oxidize rapidly in the presence of oxygen, especially at high pH values (6), and this may be the mechanism by which the interference is decreased in the time it takes to obtain and assay the HDL-containing supernate. The manganese in the heparin-Mn(fl) methods may decrease the interference in a similar way. Interference by AA, for all precipitation methods, may be insignificant for most patients’ sera, especially if the specimens are stored for at least a day at 4 #{176}C, which will result in significant losses of ascorbic acid. However, choice of a precipitation reagent such as VI apparently would minimize such interference, especially in specimens with an unusually high AA content resulting from administration of vitaminC.