Slurry sampling and fluorination–electrothermal vaporization inductively coupled plasma atomic emission spectrometry for the direct determination of molybdenum in food

Abstract

A method for the direct determination of Mo in various types of food by fluorination–electrothermal vaporization inductively coupled plasma atomic emission spectrometry has been developed and optimized. Slurry samples were prepared by ultrasonic wave vibration, after pre-treatment and direct injection into the graphite furnace using polytetrafluoroethylene as a fluorinating agent. The procedure was applied to the determination of Mo in National Institute of Standards and Technology Standard Reference Materials 1567 Wheat Flour, 1568 Rice Flour and 1577 Bovine Liver. The values found were in reasonable agreement with the certified values, with a detection limit of 0.7 ng ml^–1 and an RSD of 3.2%(n= 10) at a concentration of 0.1 µg ml^–1. The proposed procedure has been applied successfully to the analysis of various types of food samples; the recovery ranged between 92 and 105%.