In order to avoid sample contamination during sampling, we are using a Kevlar line where our Go-Flo bottles are placed. Once all the bottles are in the water we send a Teflon made messenger that closes one by one the bottles at the chosen depth. Once back in the deck, bottles are placed in our Go-Flo trolley and taken into the lab to be sampled inside the clean bubble.
My purpose, together with Luis Laglera is to measure dissolved and bioavailable iron. Respect to dissolved Fe, we are measuring different species as Fe (II) and Fe (III) with two different flow injection methods with chemiluminescence detection. In addition, Luis is measuring total dissolved and bioavailable iron by means of polarography.
Juan Santos-Echeandía blog 
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