Direct determination of arsenic in sugar by GFAAS with transversely heated graphite atomizer and longitudinal Zeeman-effect background correction
Autor(a) principal: | |
---|---|
Data de Publicação: | 2001 |
Outros Autores: | , , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Institucional da UNESP |
Texto Completo: | http://hdl.handle.net/11449/219247 |
Resumo: | A method has been developed for the direct determination of As in sugar by graphite furnace atomic absorption spectrometry with a transversely heated graphite atomizer (end-capped THGA) and longitudinal Zeeman-effect background correction. The thermal behavior of As during the pyrolysis and atomization steps was investigated in sugar solutions containing 0.2% (v/v) HNO3 using Pd, Ni, and a mixture of Pd + Mg as the chemical modifiers. For a 60-μL sugar solution, an aliquot of 8% (m/v) in 0.2% (v/v)HNO3 was dispensed into a pre-heated graphite tube at 70°C. Linear analytical curves were obtained in the 0.25 - 1.50-μg L-1 As range. Using 5 μg Pd and a first pyrolysis step at 600°C assisted by air during 40 s, the formation of a large amount of carbonaceous residue inside the atomizer was avoided. The characteristic mass was calculated as 24 pg As and the lifetime of the graphite tube was around 280 firings. The limit of detection (L.O.D.) based on integrated absorbance was 0.08 μg L-1 (4.8 pg As) and the typical relative standard deviation (n = 12) was 7% for a sugar solution containing 0.5 μg L-1. Recoveries of As added to sugar samples varied from 86 to 98%. The accuracy was checked in the direct analysis of eight sugar samples. A paired t-test showed that the results were in agreement at the 95% confidence level with those obtained for acid-digested sugar samples by GFAAS. |
id |
UNSP_ab829ba3249960842e5e0fd5fc0517bf |
---|---|
oai_identifier_str |
oai:repositorio.unesp.br:11449/219247 |
network_acronym_str |
UNSP |
network_name_str |
Repositório Institucional da UNESP |
repository_id_str |
2946 |
spelling |
Direct determination of arsenic in sugar by GFAAS with transversely heated graphite atomizer and longitudinal Zeeman-effect background correctionA method has been developed for the direct determination of As in sugar by graphite furnace atomic absorption spectrometry with a transversely heated graphite atomizer (end-capped THGA) and longitudinal Zeeman-effect background correction. The thermal behavior of As during the pyrolysis and atomization steps was investigated in sugar solutions containing 0.2% (v/v) HNO3 using Pd, Ni, and a mixture of Pd + Mg as the chemical modifiers. For a 60-μL sugar solution, an aliquot of 8% (m/v) in 0.2% (v/v)HNO3 was dispensed into a pre-heated graphite tube at 70°C. Linear analytical curves were obtained in the 0.25 - 1.50-μg L-1 As range. Using 5 μg Pd and a first pyrolysis step at 600°C assisted by air during 40 s, the formation of a large amount of carbonaceous residue inside the atomizer was avoided. The characteristic mass was calculated as 24 pg As and the lifetime of the graphite tube was around 280 firings. The limit of detection (L.O.D.) based on integrated absorbance was 0.08 μg L-1 (4.8 pg As) and the typical relative standard deviation (n = 12) was 7% for a sugar solution containing 0.5 μg L-1. Recoveries of As added to sugar samples varied from 86 to 98%. The accuracy was checked in the direct analysis of eight sugar samples. A paired t-test showed that the results were in agreement at the 95% confidence level with those obtained for acid-digested sugar samples by GFAAS.Instituto de Química Universidade Estadual Paulista, PO Box 355, 14801-970 Araraquara-SPDepartamento de Química Univ. Federal de São Carlos, São Carlos-SPInstituto de Química Universidade Estadual Paulista, PO Box 355, 14801-970 Araraquara-SPUniversidade Estadual Paulista (UNESP)Universidade Federal de São Carlos (UFSCar)Dakuzaku, Carolina S. [UNESP]Freschi, Gian P. G. [UNESP]De Moraes, Mercedes [UNESP]Nóbrega, Joaquim A.Gomes Neto, José A. [UNESP]2022-04-28T18:54:33Z2022-04-28T18:54:33Z2001-03-01info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/article271-275Atomic Spectroscopy, v. 22, n. 2, p. 271-275, 2001.0195-5373http://hdl.handle.net/11449/2192472-s2.0-0035019676Scopusreponame:Repositório Institucional da UNESPinstname:Universidade Estadual Paulista (UNESP)instacron:UNESPengAtomic Spectroscopyinfo:eu-repo/semantics/openAccess2022-04-28T18:54:33Zoai:repositorio.unesp.br:11449/219247Repositório InstitucionalPUBhttp://repositorio.unesp.br/oai/requestopendoar:29462024-08-05T21:29:30.829398Repositório Institucional da UNESP - Universidade Estadual Paulista (UNESP)false |
dc.title.none.fl_str_mv |
Direct determination of arsenic in sugar by GFAAS with transversely heated graphite atomizer and longitudinal Zeeman-effect background correction |
title |
Direct determination of arsenic in sugar by GFAAS with transversely heated graphite atomizer and longitudinal Zeeman-effect background correction |
spellingShingle |
Direct determination of arsenic in sugar by GFAAS with transversely heated graphite atomizer and longitudinal Zeeman-effect background correction Dakuzaku, Carolina S. [UNESP] |
title_short |
Direct determination of arsenic in sugar by GFAAS with transversely heated graphite atomizer and longitudinal Zeeman-effect background correction |
title_full |
Direct determination of arsenic in sugar by GFAAS with transversely heated graphite atomizer and longitudinal Zeeman-effect background correction |
title_fullStr |
Direct determination of arsenic in sugar by GFAAS with transversely heated graphite atomizer and longitudinal Zeeman-effect background correction |
title_full_unstemmed |
Direct determination of arsenic in sugar by GFAAS with transversely heated graphite atomizer and longitudinal Zeeman-effect background correction |
title_sort |
Direct determination of arsenic in sugar by GFAAS with transversely heated graphite atomizer and longitudinal Zeeman-effect background correction |
author |
Dakuzaku, Carolina S. [UNESP] |
author_facet |
Dakuzaku, Carolina S. [UNESP] Freschi, Gian P. G. [UNESP] De Moraes, Mercedes [UNESP] Nóbrega, Joaquim A. Gomes Neto, José A. [UNESP] |
author_role |
author |
author2 |
Freschi, Gian P. G. [UNESP] De Moraes, Mercedes [UNESP] Nóbrega, Joaquim A. Gomes Neto, José A. [UNESP] |
author2_role |
author author author author |
dc.contributor.none.fl_str_mv |
Universidade Estadual Paulista (UNESP) Universidade Federal de São Carlos (UFSCar) |
dc.contributor.author.fl_str_mv |
Dakuzaku, Carolina S. [UNESP] Freschi, Gian P. G. [UNESP] De Moraes, Mercedes [UNESP] Nóbrega, Joaquim A. Gomes Neto, José A. [UNESP] |
description |
A method has been developed for the direct determination of As in sugar by graphite furnace atomic absorption spectrometry with a transversely heated graphite atomizer (end-capped THGA) and longitudinal Zeeman-effect background correction. The thermal behavior of As during the pyrolysis and atomization steps was investigated in sugar solutions containing 0.2% (v/v) HNO3 using Pd, Ni, and a mixture of Pd + Mg as the chemical modifiers. For a 60-μL sugar solution, an aliquot of 8% (m/v) in 0.2% (v/v)HNO3 was dispensed into a pre-heated graphite tube at 70°C. Linear analytical curves were obtained in the 0.25 - 1.50-μg L-1 As range. Using 5 μg Pd and a first pyrolysis step at 600°C assisted by air during 40 s, the formation of a large amount of carbonaceous residue inside the atomizer was avoided. The characteristic mass was calculated as 24 pg As and the lifetime of the graphite tube was around 280 firings. The limit of detection (L.O.D.) based on integrated absorbance was 0.08 μg L-1 (4.8 pg As) and the typical relative standard deviation (n = 12) was 7% for a sugar solution containing 0.5 μg L-1. Recoveries of As added to sugar samples varied from 86 to 98%. The accuracy was checked in the direct analysis of eight sugar samples. A paired t-test showed that the results were in agreement at the 95% confidence level with those obtained for acid-digested sugar samples by GFAAS. |
publishDate |
2001 |
dc.date.none.fl_str_mv |
2001-03-01 2022-04-28T18:54:33Z 2022-04-28T18:54:33Z |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
Atomic Spectroscopy, v. 22, n. 2, p. 271-275, 2001. 0195-5373 http://hdl.handle.net/11449/219247 2-s2.0-0035019676 |
identifier_str_mv |
Atomic Spectroscopy, v. 22, n. 2, p. 271-275, 2001. 0195-5373 2-s2.0-0035019676 |
url |
http://hdl.handle.net/11449/219247 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
Atomic Spectroscopy |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
271-275 |
dc.source.none.fl_str_mv |
Scopus reponame:Repositório Institucional da UNESP instname:Universidade Estadual Paulista (UNESP) instacron:UNESP |
instname_str |
Universidade Estadual Paulista (UNESP) |
instacron_str |
UNESP |
institution |
UNESP |
reponame_str |
Repositório Institucional da UNESP |
collection |
Repositório Institucional da UNESP |
repository.name.fl_str_mv |
Repositório Institucional da UNESP - Universidade Estadual Paulista (UNESP) |
repository.mail.fl_str_mv |
|
_version_ |
1808129325736656896 |