ONLINE MICROWAVE SLURRY SAMPLE DIGESTION USING FLOW SYSTEMS FOR THE SPECTROPHOTOMETRIC DETERMINATION OF IRON IN SEAFOOD

A method for the spectrophotometric determination of iron in seafood s lurry samples based on microwave assisted digestion has been developed . The stabilized slurry (200 mu l) is introduced in a flow system and transported by an air carrier stream to a digestion coil positioned in side the microwave oven. After the digestion step (10 or 20 min at max imum power) the flushing solution is collected in a calibrated flask. A 200 mu l-digested sample is introduced in a flow injection system an d the iron determined at 512 nm with 1,10-phenanthroline. The proposed method features a linear range from 50 to 200 mu g l(-1) (r > 0.999) presenting a precision, expressed as RSD, of 3.7% (n = 10) for repeata bility and 5.0% (n = 30) for reproducibility. Accuracy was assessed by using Standard and Certified Reference Materials.