Abstract: A simple method employing inductively coupled plasma mass spectrometry (ICP-MS) for the determination of iodine content in edible algae such as kelp, undaria, hair algae, sea aedge, laver and ulva lactuca was developed. Samples were extracted by 25% tetramethylammonium hydroxide (TAMH) in closed glass bottles at 90 ℃ for 3 hours. The supernatant were diluted and determined by ICP-MS with Te as internal standard. This method displayed excellent linearity in the linear range from 10 to 500μg/L with a correlation coefficient of 0.9999. The mean recoveries in undaria samples ranged from 80% to 120% with a RSD of less than 5%, and the limit of detection for iodine was 0.50 mg/kg. This simple, rapid and sensitive method is applicable for the determination of iodine in massive samples.

Key words: iodine, inductively coupled plasma mass spectrometry, algae, tetramethylammonium hydroxide