Autor(es): Costa, Vinicius Camara ; Guedes, Wesley Nascimento [UNESP] ; Santos, Antonio de Santana [UNESP] ; Nascimento, Madson Moreira
Data: 2018
Identificador Persistente: http://hdl.handle.net/11449/164250
Origem: Oasisbr
Assunto(s): Tea leaves; Ultrasound-assisted extraction; Multivariate optimization; Box-Behnken design; ICP OES
Made available in DSpace on 2018-11-26T17:51:50Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-07-01
Fundacao de Amparo a Pesquisa do Estado da Bahia (FAPESB)
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
The current study describes a fast and efficient procedure of ultrasound-assisted extraction for determination of Ca, Mg, K, Na, Cu, Zn, Mn, and Al in tea leaves by inductively coupled plasma optical emission spectrometry (ICP OES). The variables of procedure were optimized using the Box-Behnken design and the conditions selected were nitric acid concentration (1.0 mol L-1), sonication time (7 min), and sonication temperature (75 A degrees C). The extraction efficiency was calculated using the analyte concentration obtained by a total digestion procedure as reference. Accuracy was confirmed by analysis of certified reference material of apple leaves (NIST 1515) and spinach leaves (NIST 1570a) using the procedure proposed. A statistical evaluation using Student's t test showed that there is no significant difference between the value obtained with the proposed procedure and the certified value, at 95% confidence level. The proposed procedure was successfully applied and is a good alternative to conventional acid digestion procedure and can be applied to routine analysis for determination of Ca, Mg, K, Na, Zn, Mn, Cu, and Al in tea leaves used for the preparation of infusions.
Univ Fed Sao Carlos, Grp Anal Instrumental Aplicada, BR-13565905 Sao Carlos, SP, Brazil
Univ Estadual Santa Cruz, Dept Ciencias Exatas & Tecnol, BR-45662900 Ilheus, BA, Brazil
Univ Estadual Paulista, Inst Quim, Dept Quim Analit, BR-14800060 Araraquara, SP, Brazil
Univ Fed Bahia, Inst Quim, Dept Quim Analit, Campus Ondina, BR-40170115 Salvador, BA, Brazil
Univ Estadual Paulista, Inst Quim, Dept Quim Analit, BR-14800060 Araraquara, SP, Brazil
