Cyclic voltammetry: a simple method for determining contents of total and free iron ions in sodium ferric gluconate complex

Hong Liu,Qiao Yu,Hongchun Pan,Yixuan Ma,Baoyu Liu

doi:10.5599/jese.749

Abstract

Sodium ferric gluconate complex (SFGC) is the third generation of iron supplement of polysaccharide iron (III) complex (PIC). For evaluation of technological level and application value of the prepared SFGC, it would be of great significance to determine the iron content in SFGC in a simple but effective way. This paper introduces the cyclic voltammetry (CV) method for determination of iron content in SFGC. Under established optimal experimental conditions, the content of free iron ions can be directly scanned and calculated, while the total iron content can also be determined by completely acidifying SFGC into Fe3+ ions. After optimizing and screening, the optimal scanning conditions are determined as pH 3 and 0.05 V/s of the scanning rate. Prior CV measurements, 0.4 V of the enrichment potential, and 3 min of the enrichment time are found optimal. It has also been verified that CO32- ions present in the solution show little interference in the system within the experimental range of investigation. The contents of free Fe3+, Fe2+ ions and the total iron determined after acid-hydrolysis of SFGC can be accurately calculated according to the corresponding linear relationships between peak currents and iron concentrations. In this paper, the repeatability and accuracy of the method are verified, and its feasibility as a convenient and effective method to determine the iron supplements is confirmed.

Highlights

The iron-deficiency anemia is currently the most common type of anemia, which widely exists in many countries around the world, especially in the developing countries [1,2]
No electrochemical response indicated by absence of characteristic peaks of free iron ions is observed in the scanning of 1 g/L sodium ferric gluconate complex (SFGC) solution (Figure 3c)
Determination of free iron ions in SFGC With cyclic voltammetry (CV) technique, the corresponding electrochemical characteristic peaks can be obtained by scanning free Fe3+ and Fe2+ ions under certain conditions

Summary

Introduction

The iron-deficiency anemia is currently the most common type of anemia, which widely exists in many countries around the world, especially in the developing countries [1,2]. The synthesis of hemoglobin in human’s body will be affected, resulting in inadequate oxygen supply to cells and tissues [1,3]. Iron-deficiency anemia has usually been treated by iron supplements.

Methods

Results

Conclusion