Multivariate optimization of an ultrasound-assisted extraction procedure for Cu, Mn, Ni and Zn determination in ration to chickens

• Published in: Anais da Academia Brasileira de Ciências Vol. 85; no. 3; pp. 891 - 902
• Main Authors: Barros, Joélia M, Bezerra, Marcos A, Valasques, Gisseli S, Do Nascimento, Jr, Baraquízio B, Souza, Anderson S, De Aragão, Nádia M
• Format: Journal Article
• Language: English
• Published: Brazil Academia Brasileira de Ciências 01.09.2013
• Subjects: Animal Feed - analysis; Animals; Chickens; Copper - analysis; extracao assistida por ultrassom; Manganese - analysis; metais; Metals, Heavy - analysis; MULTIDISCIPLINARY SCIENCES; Nickel - analysis; planejamento de misturas; planejamento Doehlert; racoes para frango; Spectrophotometry, Atomic; Ultrasonics; Zinc - analysis; extracao assistida por ultrassom; Doehlert design; racoes para frango; planejamento de misturas; rations to chicken; planejamento Doehlert; metals; metais; ultrasound-assisted extraction; mixture design
• ISSN: 0001-3765; 1678-2690; 1678-2690; 0001-3765
• DOI: 10.1590/S0001-37652013000300005

In this work, multivariate optimization techniques were used to develop a method based on the ultrasound-assisted extraction for copper, manganese, nickel and zinc determination from rations for chicken nutrition using flame atomic absorption spectrometry. The proportions of extracting components (2.0 mol.L-1 nitric, hydrochloric and acetic acid solutions) were optimized using centroid-simplex mixture design. The optimum proportions of this mixture taken as percentage of each component were respectively 20%, 37% and 43%. Variables of method (sample mass, sonication time and final acid concentration) were optimized using Doehlert design. The optimum values found for these variables were respectively 0.24 g, 18s and 3.6 mol.L-1. The developed method allows copper, manganese, nickel and zinc determination with quantification limits of 2.82; 4.52; 10.7; e 9.69 µg.g-1, and precision expressed as relative standard deviation (%RSD, 25 µg.g-1, N = 5) of 5.30; 2.13; 0.88; and 0.83%, respectively. This method was applied in the analytes determination from chicken rations collected from specialized commerce in Jequié city (Bahia State/Brazil). Application of paired t-test at the obtained results, in a confidence level of 95%, does not show significant difference between the proposed method and the microwave-assisted digestion.