APPLICABILITY OF VARIOUS QUALITY-CONTROL SERA TO ASSAY OF HIGH-DENSITY LIPOPROTEIN CHOLESTEROL

  • 1 January 1980
    • journal article
    • research article
    • Vol. 26  (7) , 903-907
Abstract
Effective internal quality control and external quality assessment of high-density lipoprotein [HDL] cholesterol assay are made difficult by analyte instability; the suitability of quality-control sera for this purpose was not studied. The properties of 25 different control sera from 15 suppliers were investigated by estimating within-batch precision for the 2 precipitation procedures used most widely (phosphotungstate/Mg2+ and heparin/Mn2+), with enzymic measurement of cholesterol. Some sera had properties similar to those of fresh human serum, but others demonstrated poor precision for one or both procedures, or contained apparent HDL cholesterol in unphysiological concentrations. A study of 6 sera indicated that between-batch precision was consistent with the within-batch findings. Of the 25 batches of quality-control serum investigated, 8 may be used for internal quality control, and for external quality assessment of HDL cholesterol assay.