Artículos de revistas
Assessment Of Organosilane-functionalized Nano-carbon Black For Interference-free On-line Pb(ii) Ion Enrichment In Water, Herbal Medicines And Environmental Samples
Registro en:
Analytical Methods. Royal Society Of Chemistry, v. 8, p. 2820 - 2830, 2016.
17599660
10.1039/c6ay00117c
2-s2.0-84978971033
Institución
Resumen
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) In the present work, commercial nano-carbon black (CB) particles were functionalized with 3-mercaptopropyltrimethoxysilane (3-MPTMS) through a silanization reaction to improve their adsorption capacity towards Pb(ii) ions and hence extend their application as an alternative and low-cost nanocarbonaceous material in the field of separation science. The material was characterized by FT-IR, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), Raman spectroscopy, as well as by thermogravimetric analysis and textural data. After the characterization of the material (3-MPTMS/CB) a FIA-FAAS preconcentration method for Pb(ii) ions was developed, which in turn was performed by loading 20.0 mL of a 200 μg L-1 Pb(ii) solution at pH 4.76 (buffered with 0.0358 mol L-1 acetate buffer) through 100 mg of 3-MPTMS/CB packed into a mini-column at a flow rate of 4.0 mL min-1. The optimized conditions of the proposed method have been achieved through a 25-1 fractional factorial and Doehlert matrix design. The improvements in the adsorption capacity of CB towards Pb(ii) after chemical modification with 3-MPTMS were noticed by comparing the sensitivity of the analytical curve built with CB and 3-MPTMS/CB. Very satisfactory figures of merit including a limit of detection (LOD) of 1.33 μg L-1, limit of quantification (LOQ) of 4.45 μg L-1, preconcentration factor of 28.0, consumptive index of 0.714 mL, preconcentration efficiency of 5.6 min-1 and sample throughput of 12 h-1 were obtained. The precision of the method was assessed as relative standard deviation (RSD) (%) for 10 measures of 10.0 and 160.0 μg L-1 Pb(ii) solutions yielding values of 3.0 and 2.3%, respectively. The preconcentration method was successfully applied to the Pb(ii) ion determination in different kinds of water and Ginkgo biloba samples with satisfactory recovery values (91-108%). In addition, the accuracy of the proposed method was also checked by analysis of a certified marine sediment reference material (MESS-3). © 2016 The Royal Society of Chemistry. 8
2820 2830 CAPES, Coordenação de Aperfeiçoamento de Pessoal de Nível Superior CNPq, Coordenação de Aperfeiçoamento de Pessoal de Nível Superior Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)