blood protein test (blood albumin), a blood test that measures levels of albumin, a protein that makes up approximately 60% of the total protein and whose major effect is to maintain colloidal osmotic pressure. Serum protein electrophoresis may assist in diagnosing diseases such as chronic infection, granulomatous diseases, cirrhosis, rheumatoid-collagen diseases, nephrotic syndrome, advanced cirrhosis, tuberculosis, endocarditis, and multiple myeloma, among others.