Manganese determination by GFAAS in feces and fish feed slurries

Abstract

Neste trabalho, um método simples, rápido e sensível, é proposto para determinação de manganês em amostras de fezes e rações de peixes por espectrometria de absorção atômica em forno de grafite (GFAAS) utilizando-se a introdução direta de suspensões das amostras no tubo de grafite. Os limites de detecção (LOD) e de quantificação (LOQ) calculados em relação a 20 leituras do branco das suspensões (0,50 % m/v de fezes ou ração isentas de manganês) foram de 28 e 92 μg kg -1 para as suspensões padrão de fezes e de 34 e 110 μg kg -1 para as suspensões padrão de ração. O método proposto foi aplicado em estudos de biodisponibilidade de manganês em diferentes amostras de rações de peixes e os resultados mostraram-se de acordo com os resultados obtidos utilizando-se amostras previamente mineralizadas por digestões ácidas em forno de microondas. This paper presents a simple, fast and sensitive method to determine manganese in samples of feces and fish feed by graphite furnace atomic absorption spectrometry (GFAAS) by the direct introduction of slurries into the graphite tube. The limits of detection (LOD) and quantification (LOQ) calculated for 20 readings of the blank of the standard slurries (0.50 % m/v of feces or feed devoid of manganese) were 28 and 92 μg kg -1 for the standard feces slurries and 34 and 110 μg kg -1 for the standard feed slurries. The proposed method was applied in bioavailability studies of manganese in different fish feeds and their results proved compatible with those obtained for samples mineralized by acid digestion using microwave oven.

Evaluation of Cu, Mn, and Se in Vegetables Using Ultrasonic Extraction and GFAAS Quantification

“…Argon was used as an inert gas, maintaining a constant flux of 3 L min −1 throughout the heating program except in the atomization stage, when the gas flux was interrupted. Heating programs and chemical modifiers were optimized to achieve maximum efficiency in the stages of pyrolysis and atomization of the analytes (Silva et al 2006;Silva et al 2007;Loureiro et al 2007;Neves et al 2008). Absorbance readings were made in the peak area.…”

“…After setting the optimal T P , the T A was varied in the same intervals. The heating program used in these studies is described in Silva et al 2006;Silva et al 2007;Loureiro et al 2007;Neves et al 2008). …”

Iron determination by FAAS in fish feed and feces after ultrasound-assisted extraction

“…The sample grinding procedure consisted of an initial step of 2 min of prefreezing, 1 min of pulverization, and another minute of freezing, followed by a second step consisting of two cycles of two pulverization and freezing stages, making a total of 8 min. This procedure yielded particles with a granulometry of less than 60 lm [15][16][17].…”

Total Mercury Determination in Muscle and Liver Tissue Samples from Brazilian Amazon Fish Using Slurry Sampling

“…Papers published in the last decades have highlighted slurry sampling for metal determination by graphite furnace atomic absorption spectrometry (GFAAS) as a robust technique [12][13][14]. Besides presenting such advantages as high sensitivity and low detection limits, the graphite tube allows the injection of solid sampling to be used, thus enabling the determination of volatile elements without requiring a mineralization sample step.…”

“…Besides presenting such advantages as high sensitivity and low detection limits, the graphite tube allows the injection of solid sampling to be used, thus enabling the determination of volatile elements without requiring a mineralization sample step. In this case, the volatile element can be thermally stabilized by the use of an appropriate chemical modifier [12][13][14]. The elimination of the mineralization sample step is a significant advantage in determining trace elements such as mercury, because it reduces the sample manipulation and consequently the possibility of contamination.…”