It is well known that the vanadium compounds have the effects of lowering the elevated blood glucose, cholesterol and triglycerides in diabetic rats, and that some marine organism such as ascidians and fan worm accumulate vanadium in high concentration. Therefore the development of selective determination technique for V(V) in natural water samples is an attractive topic for many researchers. In this work a simple and reliable method for the rapid extraction and determination of trace amounts of Vanadium (V) ions using Octadecyl-bonded silica membrane disks modified with 2- Mercaptopyridine-1-oxide and graphite furnace atomic absorption spectrometry(GFAAS) is presented. Extraction efficiency and influence of pH, flow rates, sample matrix, amount of ligand and type of stripping agent were evaluated. In this method the maximum capacity of membrane disk, limit of detection (LOD) and the break through volume were determined. LOD of proposed method is 2.7 ng/ mL. The maximum capacity of the membrane disks modified by 8 mg of the ligand was found to be 641.9 µg of vanadium. The break through volume is 2700 mL
