A Voltammetric Sensor Based on Iodine-Coated Platinum Electrode for Determination of Iron in Blood Serum

A novel, simple, convenient, inexpensive and green voltammetric sensing for iron in human blood serum was developed. The method is based on linear sweep voltammetry at an iodine-coated polycrystalline platinum electrode. A miniaturized home-made small scale 0.5-mL cell was used for the analysis. Oxidation of iron at the iodine-coated platinum electrode was manifested by a peak centered at 0.5 V. The established calibration curve for the relationship between iron (II) concentration and current extracted from the linear sweep voltammograms revealed an excellent linearity(R2=0.9923). The calculated lowest detection limit, LOD, is 0.26 ppm and the limit of quantification is 0.87 ppm. Recovery studies for a concentration of 1.0 ppm yielded a value of 1.02 ppm (102% percent recovery). No interference with other common essential elements in blood serum was observed which attests to the suitability and accuracy of the method. The developed method was applied to analysis of real blood samples. The results of analysis were compared with the results from conventional standard methods used in medical laboratories where an excellent agreement between the two analytical methods was observed.