Development of an Analytical Method Based in the Slurry Sampling for Iron Determination in Fortified Milk Powder by HR-C
- PDF / 201,200 Bytes
- 6 Pages / 595.276 x 790.866 pts Page_size
- 44 Downloads / 235 Views
Development of an Analytical Method Based in the Slurry Sampling for Iron Determination in Fortified Milk Powder by HR-CS FAAS Geovani Cardoso Brandao & Dalita Pedrosa Gomes & Geraldo Domingues Matos
Received: 12 April 2011 / Accepted: 4 August 2011 / Published online: 20 August 2011 # Springer Science+Business Media, LLC 2011
Abstract The use of slurry sampling as the procedure for sample preparation provides simplicity, speed, and low consumption of reagents in analytical methods. In this paper, a method based on slurry sampling for the determination of iron in samples of fortified milk powder by high-resolution continuum source flame atomic absorption spectrometry was developed. Multivariate design techniques were applied for the optimization of experimental conditions of the method for a sample mass of 100 mg, final volume of slurry of 10 mL, and using the absorbance signal as response. Initially, a two-level full factorial design was used for the preliminary evaluation of the variables involved in slurry preparation: concentration hydrochloric acid, Triton X-100 concentration, and sonication time. Then, the Doehlert matrix was applied for the determination of the critical conditions: 2.5 mol L−1 hydrochloric acid and sonication time of 20 min. External calibration technique with aqueous standard was used for the quantification of iron. This way, the method allowed iron determination with limits of detection and quantification of 0.9 and 3.0 μg g−1, respectively. The precision expressed as the relative standard deviation was evaluated under repeatability and reproducibility conditions, being 3.2% and 4.0%, respectively. Addition/recovery test was used for assessing the accuracy of the method, and the recovery values achieved were in the range of 90–110%. The method was applied for iron determination in eight samples of fortified milk G. C. Brandao (*) : D. P. Gomes : G. D. Matos Universidade Federal da Bahia, Instituto de Química, Campus Ondina, Salvador, Bahia 40170-290, Brazil e-mail: [email protected]
powder, and the obtained concentrations varied from 95.4 to 295.6 μg g−1. The results were compared with those obtained after acid digestion, and no significant difference was observed applying t test at the 95% confidence level. Keywords Slurry sampling . Iron determination . Fortified milk powder . Multivariate optimization . HR-CS FAAS
Introduction Iron is among the nutrient elements more important to the human diet. It is required for the transport of oxygen and is an essential constituent of numerous enzymes involved in diverse metabolic functions, including the production of metabolic energy, protein and DNA metabolism, collagen synthesis, and metabolism of β-carotene (Saman 2007; Sharma and Singh 2009). Due to their wide metabolic activity, iron deficiency causes serious health problems. The most severe and common form of iron deficiency is anemia, which is associated with weakness and eventually heart failure. Furthermore, iron deficiency is among the most prevalent forms of malnutrition worldwide, and
Data Loading...
