Using Ghezeljeh Nanoclay for Measuring of Copper Ions Released from the Cooking Pot into Food Samples by FAAS and ICP-AES

Ghezeljeh montmorillonite nanoclay was used as a natural adsorbent to measure and remove copper ions released from the cooking pot into food by applying the solid phase extraction (SPE) method in batch mode. The clay is characterized by using fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and X-ray diffractometry (XRD). The results of XRD and FT-IR of nanoclay confirm that montmorillonite is the dominant mineral phase. Based on SEM images of clay, it can be seen that the distance between the plates is Nano. The adsorbent was prepared using the Galehouse method and then a number of effective parameters on extraction were optimized using standard solutions: amount of adsorbent, eluent characteristics, pH and type of the buffer solutions, shaking time, adsorption temperature, volume of the standard solutions, and initial metal ion concentration. Also, the role of desorption and centrifugation time were explored. The limit of detection and quantification, preconcentration factor, and the adsorption capacity of the nanoclay were calculated. The method was applied to a variety of food materials to verify its efficiency. Subsequently, this method was applied to two Iranian stews cooked in copper pots plated with tin in order to measure the amount of copper released from the pot. The result suggests that the amounts of released copper and tin exceeded the tolerable daily intakes. In general, the removal of metal ions using the nanoclay proved to be rapid, efficient, reliable, and reproducible.