Multivariate Analysis: Use of Doehlert Design (DD) for Optimization of a Simple Sample Preparation Procedure for the Determination of Inorganic Constituents in Cocoa Beans Employing Microwave Acid Digestion and ICP OES
AUTOR(ES)
Gamela, Raimundo R.; Costa, Vinicius C.; Mello, Matheus L. de; Romero, Julia C.; Amorim, Fábio A. C.; Pereira-Filho, Edenir R.
FONTE
J. Braz. Chem. Soc.
DATA DE PUBLICAÇÃO
2020-10
RESUMO
This study presents a microwave-assisted procedure for sample preparation of cocoa beans using diluted HNO3 with H2O2 for the determination of Ba, Ca, Cu, K, Mg, Mn, P, S, Sr and Zn by inductively coupled plasma optical emission spectrometry (ICP OES). Doehlert modified design was used for optimization of experimental condition, and the volume of H2O2 (0, 0.5, 1.75 and 3 mL) and concentration of HNO3 (0.5, 3.75 and 7 mol L-1) were evaluated. The best experimental conditions were chosen considering lower residual acidity (RA), lower dissolved organic carbon (DOC) and the acceptable trueness range (80-120%), were 5 mL of 3.75 mol L-1 HNO3 and 1.75 mL of 30% v v-1 H2O2. The procedure was validate using certified reference materials (CRMs), digested using the optimized conditions. The proposed procedure was applied in twelve samples of cocoa beans, and the concentrations (mg kg-1) ranged from: 7.6-27 (Ba), 520-1955 (Ca), 11-26 (Cu), 6212-10855 (K), 1677-2516 (Mg), 13-29 (Mn), 4679-6104 (P), 1499-1898 (S), 7-32 (Sr) and 34-46 (Zn). A Pearson correlation plot was proposed to evaluate the correlation between elements, revealing high correlations between Mg and K; K and P; Cu and Mn; Cu and Zn; Cu and S.
Documentos Relacionados
- Use of Doehlert design for optimizing the digestion of beans for multi-element determination by inductively coupled plasma optical emission spectrometry
- Determination of elements in energy drinks by ICP OES with minimal sample preparation
- Use of factorial design for optimization of microwave-assisted digestion of lubricating oil.
- Use of factorial design for optimization of microwave-assisted digestion of lubricating oil
- Multivariate Optimization of a Simultaneous Cloud Point Extraction Procedure of Cd, Cu and Ni from Sediments Samples and Determination by ICP OES