A method is described for the identification of apolipoprotein E phenotypes. Lipoproteins were precipitated by magnesium chloride/phosphotungstate reagent and isoelectric focusing performed on flat-bed agarose. Sensitivity was enhanced by blotting with nitrocellulose prior to staining. The system described requires no ultracentrifugation step and allows up to 20 samples to be processed in each run. Agarose has some advantages over the more commonly used polyacrylamide gels for isoelectric focusing.
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