Flow Injection Spectrophotometric Catalytic Determination of Iodine in Milk

摘要: A flow injection method based on the catalytic action of iodide color-fading reaction FeSCN2+ complex was proposed and applied to determination iodine in milk. At pH 5.0, temperature 32°C measurements at 460 nm, decrease absorbancy Fe3+-SCN (0.10 0.0020 mol l-1) presence NO2- (0.3 is proportional concentration iodide, with linear response up 100.0 μg I- l-1. The detection limit determined as 0.99 l-1 (3σ blank/slope); system handles 48 samples h-1. Organic matter destroyed by a dry procedure carried out under alkaline conditions. Alternatively, use Schoninger combustion after milk dehydration evaluated. residue taken 0.12 KOH solubilization. For typical samples, recoveries varied from 94.5 105%, amounts both organic destroyed. accuracy established using certified reference material (IAEA A-11, powder) manual method. now an indicator quality Brazilian production system.