Determination of copper and nickel in vegetable oils by direct sampling graphite furnace atomic absorption spectrometry

• Published in: Talanta (Oxford) Vol. 70; no. 5; pp. 929 - 932
• Main Authors: Matos Reyes, Mariela N., Campos, Reinaldo C.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Amsterdam Elsevier B.V 15-12-2006; Oxford Elsevier
• Subjects: Analytical chemistry; Chemistry; Copper; Exact sciences and technology; GFAAS direct determination; Nickel; Spectrometric and optical methods; Vegetable oils; Vegetable oils; Nickel; Copper; GFAAS direct determination; Trace analysis; Human; Chemical analysis; Graphite furnace; Vegetable oil; Foodstuff; Calibration; Metal; Direct method; Detection limit; Graphite; Thermoelectric atomization; Oxidation; Sampling; Atomic absorption spectrometry
• ISSN: 0039-9140; 1873-3573
• DOI: 10.1016/j.talanta.2006.05.055

The quality of food products has been receiving great attention due to its influence on human nutrition and health. In this sense, the determination of trace metals in foods has turned an important field on food analysis. Concerning vegetable oils, its metal trace composition is an important criterion for the assessment of their quality once it is known that trace metals affect their rate of oxidation, influencing freshness, keeping properties as well as storage. In the present work an analytical method which enables the direct determination of Cu and Ni in vegetable oils by graphite furnace atomic absorption spectrometry (GFAAS), using a “solid” sample strategy is presented: in nature, samples are directly weighed on the graphite platform boat and inserted in the graphite tube. An adequate temperature program permitted the calibration by external aqueous analytical curves. Good concordance between the proposed procedure and EPA procedures was found in the analysis of real samples. Limits of detection of 0.001 and 0.002
μg
g
−1 were found for Cu and Ni, respectively, in the original samples, and they were comfortably below the concentrations found.