Determination of silicon in plant materials by laser-induced breakdown spectroscopy

Autor(es)

de Souza, Paulino Florencio ^{[1, 2]} ; Santos Junior, Dario ^[3] ; Arantes de Carvalho, Gabriel Gustinelli ^[1] ; Nunes, Lidiane Cristina ^[1] ; Gomes, Marcos da Silva ^{[4, 1]} ; Bueno Guerra, Marcelo Braga ^[1] ; Krug, Francisco Jose ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Ctr Energia Nucl Agr, BR-13416000 Piracicaba, SP - Brazil

^[2] Ctr Tecnol Canavieira, BR-13400970 Piracicaba, SP - Brazil

^[3] Univ Fed Sao Paulo, Dept Ciencias Exatas & Terra, BR-09972270 Diadema, SP - Brazil

^[4] Univ Fed Sao Carlos, Dept Quim, BR-13565905 Sao Carlos, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: SPECTROCHIMICA ACTA PART B-ATOMIC SPECTROSCOPY; v. 83-84, p. 61-65, MAY-JUN 2013.
• Citações Web of Science: 24

Resumo

In spite of the importance of Si for improving the productivity of many important crops, such as those from the Poaceae family (e.g. sugar cane, maize, wheat, rice), its quantitative determination in plants is seldom carried out and restricted to few laboratories in the world. There is a survey of methods in the literature, but most of them are either laborious or difficult to validate in view of the low availability of reference materials with a certified Si mass fraction. The aim of this study is to propose a method for the direct determination of Si in pellets of plant materials by laser-induced breakdown spectroscopy (LIBS). The experimental setup was designed by using a Q-switched Nd:YAG laser at 1064 nm (5 ns, 10 Hz) and the emission signals were collected by lenses into an optical fiber coupled to an Echelle spectrometer equipped with an intensified charge-coupled device. Experiments were carried out with leaves from 24 sugar cane varieties, with mass fractions varying from ca. 2 to 10 g kg(-1) Si. Pellets prepared from cryogenically ground leaves were used as test samples for both method development and validation of the calibration model. Best results were obtained when the test samples were interrogated with laser fluence of 50 J cm(-2) (750 mu m spot size) and measurements carried out at Si I 212.412 nm emission line. The results obtained by LIBS were compared with those from inductively coupled plasma optical emission spectrometry after oven-induced alkaline digestion, and no significant differences were observed after applying the Student's t-test at 95% confidence level. The trueness of the proposed LIBS method was also confirmed from the analysis of CRM GBW 07603 (Bush branches and leaves). (c) 2013 Elsevier B.V. All rights reserved. (AU)

• Processo FAPESP: 10/16379-0 - Estratégias de microamostragem para a análise de tecidos biológicos por espectrometria de emissão óptica com plasma induzido por laser
• Beneficiário: Gabriel Gustinelli Arantes de Carvalho
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 10/17158-8 - Avaliação da espectrometria de emissão óptica com plasma induzido por laser (LIBS) para determinação de contaminantes inorgânicos em fertilizantes agrícolas
• Beneficiário: Lidiane Cristina Nunes
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 12/16203-5 - Estratégias para análise direta de folhas de cana-de-açúcar por espectrometria de emissão óptica com plasma induzido por laser (LIBS)
• Beneficiário: Marcelo Braga Bueno Guerra
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado