The absorption efficiency of any drug in blood is of prime importance. Compounds having the general formula: , where (M = Cu(II) or Fe(III), n = 2 or 1 , FO = folate anion, x = 2 or 3 with respect), were prepared, and their absorption efficiency in rodent′s blood was determined. The obtained compounds were characterized by elemental analysis, infrared as well as thermogravimetric analysis and polarization of light. The results suggest that the two folate complexes were formed in 1 : 2 molar ratio (metal : folic acid) which acted as a bidentate ligand through both carboxylic groups. Polarization of light proved that the folate complexes have symmetric geometry. Biological application proved that Cu(II) and Fe(III) complexes were absorbed more efficiently in rodent blood than folic acid itself.