Rapid, low-sample-volume cholesterol and triglyceride assays

A method for performing a cholesterol assay, the method comprising:

• using a reagent comprising a lipoprotein solubilization agent, lipoprotein interactant, and a buffer, wherein said lipoprotein interactant is present at a concentration level that provides for conversion of high density lipoprotein cholesterol (HDL-C) to a measureable colored product at a substantially different rate than for conversion of low density lipoprotein cholesterol (LDL-C) to a measureable colored product and at a substantially different rate than for conversion of very low density lipoprotein cholesterol (VLDL-C) to a measureable colored product when said reagent is used in a cholesterol assay
• wherein said reagent comprising magnesium ions and dextran sulfate and the ratio of dextran sulfate to magnesium ions in the reagent is between about 0.002 to about 0.02;
• and
• measuring HDL-C, LDL-C, and VLDL-C in a single solution, wherein HDL-C is measured at a time different from when LDL-C is measured and different from when VLDL-C is measured,
• wherein said lipoprotein solubilization agent is a nonionic surfactant.

A method for performing a cholesterol assay, the method comprising:

• using a reagent comprising a lipoprotein solubilization agent, lipoprotein interactant, and a buffer, wherein said lipoprotein interactant is present at a concentration level that provides for conversion of high density lipoprotein cholesterol (HDL-C) to a measureable colored product at a substantially different rate than for conversion of low density lipoprotein cholesterol (LDL-C) to a measureable colored product and at a substantially different rate than for conversion of very low density lipoprotein cholesterol (VLDL-C) to a measureable colored product when said reagent is used in a cholesterol assay
• wherein said reagent comprising magnesium ions and dextran sulfate and the ratio of dextran sulfate to magnesium ions in the reagent is between about 0.002 to about 0.02;
• and
• measuring HDL-C, LDL-C, and VLDL-C in a single solution, wherein HDL-C is measured at a time different from when LDL-C is measured and different from when VLDL-C is measured,
• wherein said lipoprotein solubilization agent is a zwitterionic surfactant.