Vitamin B2

VITAMIN B2 STATUS, red blood cell (Riboflavin)
​fE-GRA(B2) ATK 8020

Riboflavin, also known as vitamin B2, is a crucial water-soluble vitamin essential for humans. It plays a vital role in various metabolic processes, contributing to the overall well-being of the body. Riboflavin is particularly important for maintaining healthy skin, nails, and hair. It exists in the form of coenzymes called flavin nucleotides, which are indispensable for facilitating oxidation-reduction reactions within cells.


Indicating vitamin B2 deficiency.


Blood sample. Requires 12 hours of fasting. Glass of water and usual medication are allowed.

No vitamin B2 supplements during 12 hours. 


6 – 7 mL Li-hep or EDTA whole blood (12 h fasting). 

Mix the sample well. The tube must not contain any clots. 

Storage and delivery

Whole blood sample: Delivery at room temperature on sampling day. The sample must arrive within 24 hours (Mon-Fri). DO NOT FREEZE!

If the sample cannot be shipped on sampling day, it must be centrifuged, plasma removed and red blood cells washed with physiological saline. (Add a saline volume equivalent to the plasma volume into the tube, mix the sample and centrifuge. After centrifugation, remove the wash solution.)

Finally, the red blood cell mass must be diluted 1:1 with aqua. The dilution is divided into two tubes and it is tested for hemoglobin (B-vit Hb), which is written on the test requisition.

The processed sample can be stored refrigerated over the weekend. Delivery at room temperature if it arrives within 24 hours.


Enzymatic method that analyses vitamin B2 (riboflavin)-dependent glutathione reductase enzyme activity. 

Reference ranges, calculated

fE-GRA(B2) 0.59 – 0.98

Turnaround time

10 weekdays

Interpretation of results

The provided figure represents the relationship between the blank sample and the stimulated sample. A larger deviation from 1 signifies a greater requirement for vitamin B2 within the body.

Baseline activity remains consistent even in the face of potential alterations in hemoglobin levels.


Last update 8.8.2023