serum phospholipid level blood very low density lipoprotein phospholipid level serum very low density lipoprotein phospholipid level 2013-05-08T13:08:27Z CMO:0001573 Measurement of the amount of phospholipid, any of various phosphorus-containing lipids that are composed mainly of fatty acids, a phosphate group, and a simple organic molecule such as glycerol, carried in very low-density lipoprotein (VLDL) molecules in a specified volume of serum, the clear liquid that separates from blood after it has clotted completely, i.e. blood plasma from which fibrinogen has been removed. VLDL constitute a class of large (e.g. approximately 30-80 nm in diameter) lipoprotein particles, complex molecules that consist of a protein membrane surrounding a core of lipids. The VLDL class of lipoproteins has a density between 0.95 and 1.006 g/ml. VT:0010507 Values for density ranges of the lipoprotein classes are approximate. The classes may be defined differently by different researchers, in part because class definitions depend on the number of subclasses into which the lipoprotein fractions are divided. clinical_measurement_ontology jsmith serum VLDL phospholipid level