This application note provides the precise determination of iodine and iodide in Lugol's solution by connecting an InMotion™ Autosampler with Excellence Titrators for complete automation.
What Is Lugol's Iodine?
Lugol’s iodine, developed by French medical doctor Lugol, is an aqueous iodine solution containing two parts of potassium iodide for every aspect of elemental iodine. Elemental iodine is not soluble in water, but the iodide present leads to the formation of soluble polyiodide ions, thereby keeping the iodine in the solution.
Lugol’s iodine solution is extensively used as a disinfectant, to visualize suspicious body tissue, differentiate and identify different types of bacteria based on the cell wall composition (gram staining), and as a reagent to determine starch.
How to Determine Iodine and Iodide?
Potentiometric titration can be used to determine iodine and potassium iodide using sodium thiosulfate and potassium iodate as the titrants, respectively. The determination can be fully automated by adapting the InMotion™ Autosampler with Excellence Titrators. A combined platinum ring electrode is used as the titration sensor for determining the equivalence point.
This Application Note Includes
- An introduction to the method
- Sample preparation and procedures
- Solutions and chemicals
- Chemistry
- Instruments and accessories
- Results and remarks
Method files (.lmt and .xml) are also included for direct import and implementation of the instrument.
Download our free application note and benefit from our experience in determining both iodine and iodide by using the Excellence titrators T5/T7/T9.
