INQUISAL 20936
INSTITUTO DE QUIMICA DE SAN LUIS "DR. ROBERTO ANTONIO OLSINA"
Unidad Ejecutora - UE
artículos
Título:
On-line solidphaseextractionofNiandPbusingcarbonnanotubesandmodified
Autor/es:
MARIANELA SAVIO; BELÉN PARODI; LUIS D. MARTINEZ; PATRICIA SMICHOWSKI; RAÚL A. GIL
Revista:
TALANTA
Editorial:
ELSEVIER SCIENCE BV
Referencias:
Año: 2011 vol. 98 p. 1 - 7
ISSN:
0039-9140
Resumen:
A studyaboutthecapabilitiesofthreekindsofnanomaterialsnamely,carbonnanotubes(CNT),oxidized carbon nanotubes(ox-CNT)and l-alanine immobilizedoncarbonnanotubes(ala-CNT)toserveassor- bents forpreconcentratingNiandPbusinganon-linesystemcoupledtoelectrothermalatomicabsorption spectroscopy (ETAAS)technique,wasaccomplished.Thesolidphaseextractionwasperformedinaconi- cal minicolumnusedassorbentholder.Afterloadingafixedvolumeoftheanalytes,theywereelutedwith a discretevolume(50 L) ofnitricacid,placeddirectlyintotheplatformofaLVovtube.Afterthat,each analyte wasdeterminedindividually.NiandPbretentionwasstronglyinfluencedbypHbutexhibit- ing differentbehaviors.Thestudydemonstratedthatthesorbentbasedonox-CNTswastheonethat exhibited thehighestcapacityandlinearityforbothanalyteswhencomparedwithCNTorala-CNT.The analytical performancewasevaluatedforthethreesorbentstoestablishthebestconditionsregarding sensitivity, reproducibilityandaccuracy.Theprecisionexpressedasrelativestandarddeviations(n=6) were 3.9and0.5%forNi2+ and Pb2+, respectivelyThelimitofdetection(LOD),calculatedastheconcen- tration requiredtoyieldanetpeakequaltothreetimesthestandarddeviationofthebackgroundsignal (3) was30and10ngL−1 for Ni2+ and Pb2+ respectively. Alternatively,thelimitofquantification(10) was calculatedandresultedtobe0.79and0.07 gL−1 for Ni2+ and Pb2+ respectively. Afteroptimization, the methodthatinvolvedtheuseofox-CNTassociatedtoanon-linepreconcentrationwastestedin samples ofrelevantenvironmentalimportance.Accuracywasevaluatedanalyzingacertifiedreference material namely,MunicipalSludge(QCMUNICIPALSLUDGEA)andareferencesampleofLakeSediment (TRAP-LRM fromIJS). l-alanine immobilizedoncarbonnanotubes(ala-CNT)toserveassor- bents forpreconcentratingNiandPbusinganon-linesystemcoupledtoelectrothermalatomicabsorption spectroscopy (ETAAS)technique,wasaccomplished.Thesolidphaseextractionwasperformedinaconi- cal minicolumnusedassorbentholder.Afterloadingafixedvolumeoftheanalytes,theywereelutedwith a discretevolume(50 L) ofnitricacid,placeddirectlyintotheplatformofaLVovtube.Afterthat,each analyte wasdeterminedindividually.NiandPbretentionwasstronglyinfluencedbypHbutexhibit- ing differentbehaviors.Thestudydemonstratedthatthesorbentbasedonox-CNTswastheonethat exhibited thehighestcapacityandlinearityforbothanalyteswhencomparedwithCNTorala-CNT.The analytical performancewasevaluatedforthethreesorbentstoestablishthebestconditionsregarding sensitivity, reproducibilityandaccuracy.Theprecisionexpressedasrelativestandarddeviations(n=6) were 3.9and0.5%forNi2+ and Pb2+, respectivelyThelimitofdetection(LOD),calculatedastheconcen- tration requiredtoyieldanetpeakequaltothreetimesthestandarddeviationofthebackgroundsignal (3) was30and10ngL−1 for Ni2+ and Pb2+ respectively. Alternatively,thelimitofquantification(10) was calculatedandresultedtobe0.79and0.07 gL−1 for Ni2+ and Pb2+ respectively. Afteroptimization, the methodthatinvolvedtheuseofox-CNTassociatedtoanon-linepreconcentrationwastestedin samples ofrelevantenvironmentalimportance.Accuracywasevaluatedanalyzingacertifiedreference material namely,MunicipalSludge(QCMUNICIPALSLUDGEA)andareferencesampleofLakeSediment (TRAP-LRM fromIJS).
