Optimization of Milk Sample Cleanup Using Response Surface Methodology
- PDF / 915,396 Bytes
- 10 Pages / 595.224 x 790.955 pts Page_size
- 112 Downloads / 254 Views
Optimization of Milk Sample Cleanup Using Response Surface Methodology Lucas Ulisses Rovigatti Chiavelli1 · Antonio Cesar Godoy1 · Roberta da Silveira1 · Patricia Daniele Silva Santos1 · Tiago A. M. Lopes1 · Oscar Oliveira Santos1 · Jesu´ı Verg´ılio Visentainer1 Received: 27 March 2019 / Accepted: 13 June 2019 © Springer Science+Business Media, LLC, part of Springer Nature 2019
Abstract Protein precipitation is a fast and simple methodology for sample preparation in milk, performed by addition of an organic solvent compatible with the analytical system. Therefore, the aim of this study is to compare four organic solvents efficiency: (i) acetonitrile, (ii) acetone, (iii) ethanol, and (iv) isopropanol for deproteinization. Acetonitrile was the most efficient at freezer temperature, while at room temperature the most efficient solvent was acetone. In order to optimize precipitation conditions, two central composite designs (CCDs) associated with response surface methodology (RSM) were performed using acetonitrile as precipitant. ANOVA was applied to the experimental designs and data were adjusted to quadratic model with high order of significance, suitable adjustment of the experimental data, with Adjusted-R 2 > 0.98, and adequacy precision desirable. For models’ optimization and validation, the desirability function was performed, and under the optimized conditions, which were obtained with a total desirability value of 1.000, the experimental values are statistically equal to predicted values for protein. The volume of precipitant and the ultrasound time were significant on the response, whereas the vortex time was a non-signifcant factor. The RSM was applied efficiently in the optimization process allowing the simultaneous evaluation of the variables on the response. Keywords Milk · Sample preparation · Protein precipitation · Precipitant solvent · Central composite design
Introduction Milk is an important source of high-quality nutrients, such as minerals, vitamins, essential fatty acids, and amino acids, to general population (Neumann et al. 2002). As the demand of this product has been increasing, it is necessary to maintain and verify its high-quality nutrients, and the possible contaminants’ presence (i.e., antibiotic residual) using different analyses methods (Raza and Kim 2018). The milk matrix complexity is challenging, in order to achieve an efficient sample preparation and adequate sensitivity for analyses involving liquid chromatographytandem mass spectrometry (LC-MS/MS). Besides, milk matrix components coeluting with the interest compound
Lucas Ulisses Rovigatti Chiavelli
[email protected] 1
Centro de Ciˆenicas Exatas - Departamento de Qu´ımica, Universidade Estadual de Maring´a, Av. Colombo, 5790, Maring´a/PR, Brazil
could interfere in the ionization process in the mass spectrometer, causing ionization suppression or enhancement of the analyte; furthermore, it could contribute to an accentuated wear of the chromatographic column (Souverain 2004). Among these interfering components, pro
Data Loading...
