Practical investigations
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I would like to know the extraction procedures for seaweeds using various solvents for the antiviral, antimicrobial and therapeutic properties investigations.
Igloo writes ...
The stages involved in extracting iodine, which is presumably what you are interested in, are briefly as follows:
1 Burn a small sample of dried seaweed to ash by heating it strongly on old tin lid. This operation must be carried out in a fume cupboard.
2 Transfer the ash to a beaker, and boil with some water for about 5 minutes
3 Filter the mixture into a boiling tube, and add a small volume of dilute sulphuric acid and dilute hydrogen peroxide to the filtrate. The mixture at this stage should turn yellow, orange or brown, showing that iodine is now present in aqueous solution. If the mixture remains colourless no iodine has been formed!
This method depends on choosing a variety of seaweed with a high enough iodine content. If you are unsuccessful with one variety, try another. I’ll leave you to research how solid iodine might be obtained from the aqueous solution (hint: use solvent extraction – look this up on the web)
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Risk assessment
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updated: 13 January 2007
