The key difference between ferrous gluconate and ferrous sulfate is that ferrous gluconate is more absorbed into our bodies than ferrous sulfate.
Iron is a metal in the d block with the symbol Fe. It is the fourth most common element in the earth’s crust. Iron has oxidation states ranging from −2 to +8. Among these +2 and the +3 forms are the most common. +2 Oxidation form of iron is known as ferrous and +3 form is known as ferric. These ions are in the form of ionic crystals, which are formed with various anions. Iron is needed for biological systems for various purposes. For example, in humans, ferrous is found as a chelating agent in haemoglobin. It is also important for the chlorophyll synthesis in plants. Hence, when there is a deficiency of ion, biological systems show various diseases. Ferrous gluconate and ferrous sulfate are two ionic compounds that can be given as ferrous supplements to overcome iron deficiencies in living systems.
CONTENTS
1. Overview and Key Difference
2. What is Ferrous Gluconate
3. What is Ferrous Sulfate
4. Side by Side Comparison – Ferrous Gluconate vs Ferrous Sulfate in Tabular Form
5. Summary
What is Ferrous Gluconate?
Ferrous gluconate is an iron salt of gluconic acid. The carboxylic acid group of the gluconic acid reacts with ferrous to produce this salt. Two gluconate ions interact with the ferrous ion when producing this salt. It has the molecular formula of C12H24FeO14. The molar mass of the compound is 448.15. Ferrous gluconate has the following structure.
This is a solid, which has a light yellow to brown/black appearance and a slight caramel odour. Ferrous gluconate is soluble in water. It is used as an iron supplement to the body. In the market, ferrous gluconate is marketed under brand names like Fergon, Ferralet, and Simron. For diseases like hypochromic anaemia, caused due to the lack of iron in the body, ferrous gluconate can be given. Further, ferrous gluconate is used as a food additive.
What is Ferrous Sulfate?
Ferrous sulfate is an ionic compound with the chemical formula FeSO4. It may exist in different crystal types depending on the number of water molecules attached. It has anhydrous, monohydrate, tetrahydrate, pentahydrate, hexahydrate and heptahydrate forms. Among these, the blue-green colour heptahydrate form is the most common. Monohydrate, pentahydrate and hexahydrate forms are relatively rare. In addition to blue-green colour crystals, other forms of ferrous sulfate are mostly white coloured crystals.
When heated, the hydrated crystals lose water and become anhydrous solids. Upon further heating, it is decomposed into sulfur dioxide, sulfur trioxide and iron(III) oxide (reddish-brown colour). They are odourless crystals. Ferrous sulfate readily dissolves in water and ferrous ion forms the hexa aqua complex, [Fe(H2O)6]2+. Ferrous sulfate is used to treat conditions of iron deficiencies like iron deficiency anaemia. It is also added to plants, as well. In conditions like iron chlorosis, where plant leaves become yellow, pale colour ferrous is given. Moreover, it is used as a precursor to synthesize other compounds. Since it is a reduction agent, it is used for redox reactions, as well.
What is the Difference Between Ferrous Gluconate and Ferrous Sulfate?
In ferrous gluconate, the ferrous anion is combined with an organic anion. In ferrous sulfate, the anion is inorganic. Ferrous gluconate is a large compound compared to ferrous sulfate. Ferrous sulfate is abundant in nature compared to ferrous gluconate. When given as a supplement, ferrous gluconate is more absorbed into our bodies than ferrous sulfate.
Summary – Ferrous Gluconate vs Ferrous Sulfate
Ferrous gluconate is an iron salt of gluconic acid and Ferrous sulfate is an ionic compound with the chemical formula FeSO4. These are iron supplements used to treat or prevent iron deficiency. The key difference between ferrous gluconate and ferrous sulfate is that ferrous gluconate is more absorbed into our bodies than ferrous sulfate.
Image Courtesy:
1. “Ferrous gluconate” By Edgar181 – Own work (Public Domain) via Commons Wikimedia
2. “Fe(H2O)6SO4” By Smokefoot – Own work (CC BY-SA 4.0) via Commons Wikimedia