Preparation
Calcium Gluconate Prepared by reacting calcium carbonate or calcium hydroxide with gluconic acid (obtained through the fermentation of glucose by bacteria or fungi, such as Aspergillus niger):
CaCO3 + 2C6H12O7 → Ca(C6H11O7)2 + CO2
Ca(OH)2 + 2C6H12O7 → Ca(C6H11O7)2 + 2H2O
Properties
White or off-white, odorless, crystalline powder or granules
Slightly soluble in water, forming a clear, colorless solution
Practically insoluble in alcohol and ether
A salt of gluconic acid and calcium, containing Ca²⁺ and gluconate ions (C₆H₁₁O₇⁻)
Uses
Used in electrolyte replacement therapy to treat hypocalcemia (low calcium levels in the blood)
Can be administered orally or intravenously based on the severity of the deficiency
Used as an antidote for hyperkalemia, magnesium toxicity, and calcium channel blocker overdose in emergency medicine
Used as a calcium supplement in cases of calcium deficiency, such as osteoporosis, rickets, and hypoparathyroidism
Assay
Typically involves complexometric titration using a chelating agent like ethylenediaminetetraacetic acid (EDTA)
Performed in the presence of an indicator like Eriochrome Black T or Calcon, which changes color at the endpoint
The calcium ions are chelated with the EDTA solution, and the amount of EDTA consumed is used to calculate the percentage of calcium gluconate in the sample