Evaluation of sample preparation methods based on alkaline and acid solubilization for the determination of Na and K in meat samples by atomic spectrometric techniques

Abstract

Foram avaliados dois métodos diferentes de preparo de amostras de carnes baseados na solubilização em meios alcalino ou ácido. O objetivo deste estudo foi determinar os teores de Na e K após solubilização com hidróxido de tetrametilamônio (TMAH) à temperatura ambiente, e com ácido fórmico e aquecimento em bloco de digestão a 50 ºC por cerca de 2 h. A solubilização alcalina se apresentou como uma metodologia simples e robusta e a melhor alternativa frente aos procedimentos de mineralização convencional, permitindo a solubilização completa das amostras usando pequenas quantidades de TMAH. O método foi validado empregando-se materiais de referência certificada assim como pela comparação com método de digestão convencional com ácido nítrico. Os limites de detecção obtidos foram de 0,8 e 2,0 mg g -1 para Na e K, respectivamente, e se mostraram adequados para o objetivo das análises.Two different sample preparation methods were evaluated for meat samples employing the solubilization in alkaline or acidic media. The aim of this study was to determine Na and K levels after sample solubilization with tetramethylammonium hydroxide (TMAH) at room temperature, and with formic acid and heating in a digester block at 50 ºC for ca. 2 h. The alkaline solubilization showed to be a simple and robust method and the better alternative in relation to the mineralization conventional procedures, allowing the complete solubilization of the samples even when small quantities of TMAH were used. The method was validated by using certified reference material as well as by comparing with samples digested with nitric acid. The limits of detection obtained were 0.8 and 2.0 μg g -1 for Na and K, respectively, and showed to be adequate for the analysis purposes.

Detection and Validation Studies of Trace Metals, Protein and Steroid in Different Organs of Local and Brand Meat (Poultry, Cattle and Fish)

“…The Na metals at 589 nm emits perky yellow flame and K at 766 nm displays mauve color. The meat samples were prepared according to the method describes by da Silva et al (2012) and subjected to flame photometer, the concentration of metal in every single sample was recorded.…”

Synthesis and application of ion-imprinted polymer for extraction and pre-concentration of iron ions in environmental water and food samples

“…Then, 10 mL of concentrated nitric acid was added to sample and the mixture was heated at 220 o C for 1 h. After cooling to room temperature, 5 mL hydrogen peroxide was added to the mixture and heated for 1 h and resulting mixture was diluted by deionized water [21,22], adjustment of the pH was performed by using of sodium hydroxide and hydrochloric acid. A C C E P T E D M A N U S C R I P T ACCEPTED MANUSCRIPT 10 …”

Determination of Zn and Mg in Milk Powder Samples Using Conventional and Alternative Sample Preparations and FAAS

“…It presents advantages when compared to liquid milk, such as ease of storage and transport, and perishability. Considering the internationally marketed dairy products, milk powder is the product with the highest volume of transactions, and Brazil stands out as one of the largest producers of whole milk powder [1].…”

“…However, this analytical technique requires a sample pretreatment [2]. The conventional methods of sample preparation involve digestion with oxidizing acids and heating or calcination, and both techniques are laborious and require a high operating time, besides the risk of contamination and volatilization due to the number of steps [1,2].…”