Flow-Injection Flame Atomic Absorption Spectrometric Determination of Trace Amounts of Cadmium in Solid and Semisolid Milk Products Coupling a Continuous Ultrasound-Assisted Extraction System with the Online Preconcentration on a Chelating Aminomethylphosphoric Acid Resin

Abstract

A new sensitive and low-cost method that combines continuous acid extraction, online preconcentration, and flame atomic absorption spectrometry for cadmium determination at g levels in solid and semisolid milk products is described. A continuous ultrasound-assisted extraction system is used to carry out the dynamic acid extraction step. The acid extract is preconcentrated online on a minicolumn packedwith a chelating resin (Chelite P,with aminomethylphosphoric acid groups), and the retained cadmium is elutedwith hydrochloric acid and continuously monitored by flame atomic absorption spectrometry. An experimental design (Plackett-Burman 263/16) is used to optimize the continuous extraction and the preconcentration step. The method allowed a total sampling frequency of 28 samples/h. A good precision of the whole procedure (3.0% relative standard deviation) for a cheese sample containing 0.103 0.004 g/g Cd (dry mass), a high enrichment factor (20.5), and detection and quantification limits of 0.014 and 0.067 g/g, respectively, for a 60 mg of sample were obtained with this methodology. The method was successfully applied to the determination of trace amounts of cadmium in solid and semisolid milk products, such as cheese and yogurt samples.

Comparative Study of Heavy Metals in Dried and Fluid Milk in Peshawar by Atomic Absorption Spectrophotometry

“…Milk is the first food that human encounters which serves as a source of essential nutrients required for the biological functions and growth during early stages of life [ 1 ], so commercial infant formulae are designed to mimic the composition of human milk [ 2 ]. Formula requiring dilution needs to be measured to correct proportions as the dangers of imbalance exist if excessively concentrated formula or undiluted cow's milk is fed because of preparation error or ignorance [ 3 ]. Evaporated and commercially prepared formulae are more expensive than fresh or liquid milk [ 4 ].…”

A Rapid Routine Methodology Based on Chemometrics to Evaluate the Toxicity of Commercial Infant Milks Due to Hazardous Elements

“…and undergo aggressive treatments, such as for example protein hydrolysis. Moreover, infant milks are fortified with essential elements considered nutrients, such as Fe, Zn and Cu, mixed during the manufacturing process at high temperatures and pressures in tanks (Cancela and Yebra, 2006;Hozyasz and Ruszczynska, 2004;Khan, 2008;Landigran et al, 2002;Leotsinidis et al, 2005;Lima de Paiva et al, 2019). Fe is present in all human cells, participates as a catalyst in several metabolic reactions and its deficiency causes anemia, developmental delays and behavioural disturbances.…”