Description
Vitamin B2 is a component of the flavin nucleotides and as such is involved in the transport of hydrogen ions and electrons. It is an essential coenzyme for the
metabolism of carbohydrates, fats and proteins. The biological form of vitamin B2 is riboflavin-5-phosphate. The most important vitamin B2 derivatives are flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD). In blood, about 60% of FAD and FMN are protein bound; only about 0.5–2% occur in free form. Riboflavin 5-phosphate, FMN, and FAD are transported in the plasma by a variety of proteins, including albumin, fibrinogen, riboflavin-binding protein and other globulins. Although vitamin B2 is eliminated regularly in the urine, its determination in urine samples is not recommended because of fluctuations in the concentration.
