Plasma and RBC concentration of folate and vitamin B-12 were determined using a commercially available RIA kit[Simul TRAC Radioassay Kit-Vitamin B-12(57Co/Folate(I125)Germany], with a sensivity of 1.5 nMol/L for serum folate,120ng/ml for RBC folate and120pMol/l for Vitamin B-12. For Red Cell Folate assay , you had to determined and recorde the Hematocrite value. then calculated red cell folate values from whole blood folate concentration and corrected for hematocrite and plasma folate level according to established formula whichis in your kit