Albumiinia

Albumiinia is a term most often associated with albumin, the major water-soluble protein in blood plasma. In some contexts, it is used in reference to albuminuria, the presence of albumin in urine, which can signal kidney dysfunction. Albumin is the most abundant plasma protein and plays a central role in maintaining oncotic pressure, transporting a wide range of substances, and contributing to antioxidant defenses.

Human serum albumin is a single polypeptide chain of about 585 amino acids, with a molecular weight of roughly 66.5 kilodaltons. It consists of three homologous domains that form a flexible structure capable of binding diverse ligands, including fatty acids, medications, bilirubin, hormones, and metal ions. The protein is synthesized mainly by hepatocytes in the liver, with a normal serum concentration typically around 35–50 g/L. Its half-life in the circulation is approximately 20 days and its production is influenced by nutritional status, liver function, and inflammatory conditions.

Clinically, low albumin levels (hypoalbuminemia) can result from liver disease, nephrotic syndrome, malnutrition, inflammation, or protein-losing enteropathies, and are associated with edema and poorer outcomes in various illnesses. The presence of albumin in urine, albuminuria, is a sensitive marker of kidney damage, particularly in diabetes and hypertension, and is used to assess kidney disease risk and progression. Measurement methods include the urine albumin-to-creatinine ratio and, for screening, urine dipstick tests, though more precise assays are preferred for quantification.

In laboratory settings, albumin from bovine serum (BSA) is widely used as a protein standard and stabilizer in biochemical assays and research applications.