Formation of volatile iodine compounds under hot concentrated acid conditions (nitric acid or aqua regia) and in diluted acid solutions with or without thiocyanate

Edible Macroalgae: Beneficial Resource of Iodine

“…The overall range of the iodine level in macroalgae is very broad, because they may contain from only a few ppm to several thousand ppm of iodine [7,12,20,[25][26][27][28][29][30][31]. Brown macroalga Laminaria sp.…”

“…is the best accumulator of iodine with its average content of almost 0.3% of dry weight, thus representing 104 more concentration of this element in comparison with seawater [12,26]. In studies in the lagoon of Venice, brown macroalgae species Sargassum muticum and Undaria pinnatifida (Wakame) collected from the depth at 50 cm, showed concentrations of 177ppm and 583ppm, per dry weight (dw), respectively [25]. Similarly, U. pinnatifida (Wakame) imported from Japan had iodine content equal to 260 ppm (dw), whereas Laminaria digitata japonica (Konbu) contained as much as 1700ppm (dw) of total iodine [27].…”

A procedure for the quantification of total iodine by inductively coupled plasma mass spectrometry, and its application to the determination of iodine in algae sampled in the lagoon of Venice

“…Very low sensitivities (not reported in Table 1) were also observed when I 2 was analyzed without the addition of 0.1 M SCN À ; this was due to the I 2 volatilization in the aerosol. 17,21,[26][27][28] The addition of 0.1 M SCN À led to the formation of the I 2 SCN À complex 21 that avoided volatilization. The calibration sensitivity value increased to the same order of magnitude as for the other iodine species (Table 1).…”

“…Iodine volatilization and loss may also occur during aerosol formation in the pneumatic nebulizer of the ICP-MS, and this process can cause severe memory effects affecting the reproducibility of the results. 15,19,20 In our previous paper 21 the chemistry of iodine in HNO 3 or HNO 3 /HCl solutions was studied. Briey, it was shown that any iodine compound is partly reduced to volatile/insoluble I 2 by nitrogen oxides in hot concentrated HNO 3 .…”

“…The rst goal of this work was to set up a procedure for the ICP-MS analysis of iodine, which should avoid the loss of iodine during and aer the mineralization and in the spray chamber. On the basis of the previous work 21 the mineralization medium for samples containing iodine should be AR, and the diluted solution obtained aer mineralization should be added with 0.1 M SCN À prior to the injection into the ICP-MS. The calibration sensitivity was checked in several media and with different SCN À counterions, and the best calibration conditions for the ICP-MS analysis of iodine were individuated.…”