iodine extraction

[milpol]

Hi to everyone,
I have used different techniques to characterize iodine and other inorganic elements in algae, but I haven't found any technique to extract iodine.
I know that algae contains a large amount of this element and that in the past algae where one of the source of iodine, but I don't know how to extract it.
Thanks in advance
milpol

[danfive]

Look into alkaline extraction of iodine in biological samples:

"Extraction of iodine
A portion (200–500 mg) of the sample is weighed out into a flask. Dry samples need addition of 5 ml of water and thorough mixing to obtain a homogeneous solution or suspension. For samples with large amounts of water, the amount taken can be raised to 2–3 g. A 1 ml volume of TMAH (25%) is added, the bottle closed gas-tight and placed in a dry oven at 90±3 °C.
After 3 h the sample is allowed to cool before being diluted with water to a final volume of 25 ml. Undissolved particles need to be removed by centrifugation or filtration through a membrane filter (e.g., 5 mm). In order to avoid clogging of nebulizer, final filtration through a 0.45 mm membrane filter is recommended. The remaining solution should be visually clear in most cases. However, some degree of turbidity will remain in samples containing starch, but this will not cause clogging of the nebulizer. This solution can be measured directly or after dilution, depending on the amount of matrix present."
from---> http://www.rsc.org/ej/JA/1998/a801671b.pdf

[ylu]

Hi, Hope not too late to answer your question. I did my master on iodine, here is the method I used for total iodine measurement.

Fresh seaweed was cleaned, air-dried at room temperature (20±1◦C), and ground in a quartz grinder then passed through a 500-µm sieve. Twenty to fifty milligrams of seaweed powder was weighed accurately into a 50-mL round bottom flask, mixed with 3mLTMAH (25% w/w), and refluxed for 4 h. The digestion solution was centrifuged at 2000g for 6–10 min to separate undissolved matter. An aliquot was taken and
diluted to 10mL with deionized water. The TMAH concentration in the final solution was adjusted to no more than 1% (v/v). Duplicates were prepared.

If you want to go for more details,here is the publication: Y. Lu et al., Environ. Chem. 2006, 3, 338–344.
By the way, if you want more details, please let me know. I was handling very high iodine concentration in my algae samples, so the amounts I used was only 20-50 mg.
Hope this help.

[admin]

Thanks ylu,
that will help many and it was interesting to know how it was done for me too

[milpol]

Thanks to everyone for the help.

[danfive]

Thanks for adding your comment ylu.