University of North Florida
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Stuart Chalk, Ph.D.
Department of Chemistry
University of North Florida
Phone: 1-904-620-1938
Fax: 1-904-620-3535
Email: schalk@unf.edu
Website: @unf

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Yaneira Petit De Pena

Abbrev:
Petit De Pena, Y.
Other Names:
Yaneira Petit de Peña, Y. Petit de Peña
Address:
Venezuelan Andean Institute for Chemical Research, Faculty of Sciences, Los Andes University, P.O. Box 542, Merida 5101-A, Venezuela
Phone:
+58-274-2401375
Fax:
+58 274 2401390
Email:
ypetit@ula.ve

Citations 4

"Continuous Flow System For Lead Determination By Faas In Spirituous Beverages With Solid Phase Extraction And On-line Copper Removal"
Talanta 2004 Volume 64, Issue 5 Pages 1351-1358
Yaneira Petit de Peña, Boris Paredes, Wendy Rondón, Marcela Burguera, José Luis Burguera, Carlos Rondón, Pablo Carrero and Tarcisio Capote

Abstract: A continuous flow system for the determination of lead in home made spirituous beverages was developed. The determination was based on the formation of a neutral chelate of the element with ammonium pyrrolidine dithiocarbamate, its adsorption onto a minicolumn packed with sodium faujasite type Y synthetic zeolite, followed by elution with methyl isobutyl ketone and determination by flame atomic absorption spectrometry. Ethanol and copper interfere strongly in the determination and therefore, must be separated prior to the analysis. Copper is removed by precipitation with rubeanic acid, while ethanol is eliminated by rotaevaporation. Sample solutions containing Pb2+ in the concentration range from 5 to 120 µg L-1 at pH 2.5 could be analyzed, by using a pre-concentration time of 3 min. Preconcentration factors from 80 to 140 were achieved for a sample volume of 6 mL and the detection limit varied from 1.4 to 3.5 µg l-1, depending on the matrix composition. The relative standard deviations for 60 µg L-1 Pb was 3.2% (n = 10) and the recovery of spikes (20, 40, 60 and 80 µg l-1) added to the samples was estimated within 92-105% range, suggesting that lead can be quantitatively determined in such samples. Determining lead in several samples by an alternative technique further checked the accuracy. Finally, the concentrations of Pb2+ determined in 28 samples of Venezuelan spirituous beverages were in 12.6-370.0 µg L-1 range, depending on the fermenting material based on different mixtures of agave, raw sugar cane and white sugar.

"On-line Determination Of Antimony(III) And Antimony(V) In Liver Tissue And Whole Blood By Flow Injection-hydride Generation-atomic Absorption Spectrometry"
Talanta 2001 Volume 55, Issue 4 Pages 743-754
Y. Petit de Peña, O. Vielma, J. L. Burguera, M. Burguera, C. Rondón and P. Carrero

Abstract: A new analytical procedure for the speciation of antimony in liver tissues is presented here. For this purpose, a flow injection system has been developed for the treatment of samples and the determination of antimony by hydride generation-atomic absorption spectrometry. The method involves the sequential and the on-line extraction of antimony(III) and antimony(V) from solid lyophilized blood and hamsters liver tissues, with 1.5 mol L-1 acetic acid and 0.5 mol L-1 sulfuric acid for Sb(III) and Sb(V), respectively. Reduction of Sb(V) to Sb(III) for stibine generation is effected by the on-line pre-reduction with L-cysteine. The linear ranges were 2.5-20 and 1.0-25 µg L-1 of Sb(III) and Sb(V), respectively. The detection limits (3s) were 1.0 µg L-1 for Sb(III) and 0.5 µg L-1 for Sb(V). The relative standard deviation values for fifteen independent measurements were 2.1 and 1.8% for Sb(III) and Sb(V), respectively. The recovery studies performed with samples of cattle liver provided results from 98 to 100% for Sb(III) and from 100 to 103% for Sb(V) for samples spiked with single species. For samples spiked with both Sb(III) and Sb(V), the recovery varied from 97 to 103% for Sb(III) and from 101 to 103% for Sb(V). (C) 2001 Elsevier Science B.V. All rights reserved.
Interferences

"Flow Injection System For Cadmium Preconcentration On Poly(octadecyl Diitaconate) (PDI-18) And Atomic Absorption Spectrometry Detection"
Anal. Chim. Acta 2001 Volume 438, Issue 1-2 Pages 259-266
Y. Petit De Peña, W. López, M. Burguera, J. L. Burguera, López-Carrasquero and M. Carrillo

Abstract: This work assesses the potential of a new adsorptive material: poly(octadecyl diitaconate) (PDI-18), for the pre-concentration of cadmium traces. The procedure involves the formation of a neutral cadmium chelate with ammonium pyrrolidinedithiocarbamate (APDC) as chelating reagent, its adsorption on PDI-18 minicolumns, and its elution with 300 µl of methyl isobutyl ketone. Using 20 mg of the sorbent material with a loading time of 2 min per sample, pre-concentration factors of cadmium of 110 were readily achieved related to the direct introduction of aqueous solutions into an atomic absorption spectrometer. To evaluate the performance of this material, a flow injection system was used for samples of water from different sources, and the accuracy was assessed through recovery experiments and using certified reference materials. All the analytical results obtained were in good agreement with the certified values. The linear range, the detection limit (3s) and the relative standard deviation at 2 ng mL-1 were 0.5-5.0 ng mL-1, 0.08 ng mL-1 and 2.1%, respectively. The effect of various ions on the determination of cadmium was investigated in order to evaluate the selectivity of the new sorbent material.

"Synthetic Zeolites As Sorbent Material For On-line Preconcentration Of Copper Traces And Its Determination Using Flame Atomic Absorption Spectrometry"
Anal. Chim. Acta 2000 Volume 403, Issue 1-2 Pages 249-258
Yaneira Petit de Peña, Wilmer López, José Luis Burguera, Marcela Burguera, Máximo Gallignani, Rosario Brunetto, Pablo Carrero, Carlos Rondon and Freddy Imbert

Abstract: This work assesses for the first time the potential of synthetic zeolites as adsorptive material for the pre-concentration of copper traces. This involves the formation of a copper chelate, its adsorption on sodium lynde Type A (Na-LTA) and sodium faujasite Type X (Na-Fau) synthetic zeolite minicolumns, and its elution with 300 µl of methyl isobutyl ketone. Using 5-80 mg of either sorbents materials with a loading time of 2 min per sample pre-concentration factors of copper ranging from 35-125 for Na-LTA and 3065 for Na-Fau were readily achieved related to the direct introduction of aqueous solutions into an atomic absorption spectrometer. To evaluate the performance of these materials, a flow injection system was used for samples of water from different sources, and the accuracy was assessed through recovery experiments and the analysis of certified reference materials. A parallel experiment was performed with polygosyl bonded silica reversed-phase sorbent with octadecyl functional groups (RP-C-18) as sorbent in the minicolumn in order to study the performance of this. well-known material as a reference for the new sorbents. The 3s detection limits, relative standard deviation and linear calibration graphs were, respectively, 0.1 ng mL-1, 2.6% and 2.5-30 ng mL-1 for Na-LTA and 0.4 ng mL-1, 2.8% and 2.5-40 ng mL-1 for Na-Fau for pre-concentration times of 2 min.
Copper Sea Spectrophotometry Preconcentration Activated carbon Reference material C18 MIBK Column