Influência de nitrato de paládio, nitrato de magnésio e nitrato de níquel no comportamento térmico de arsênio em açúcares por espectrometria de absorção atômica em forno de grafite
Main Article Content
Abstract
A influência de digeridos e suspensões de açúcar no comportamento térmico de As usando Pd(NO3)2, Pd(NO3)2 + Mg(NO3)2, and Ni(NO3)2 como modificadores químicos foi investigada. Influência de 0,2%, 5%, 10% e 35% (v/v) HNO3 na calibração (1,00 - 10,0 µg As L-1) também foi feita. Um volume de 20 µL de amostra mais 5 µL Pd ou 5 µL Pd + 3 µL Mg, ou 20 µL Ni foi injetado no atomizador do GF AAS. Para cada modificador, temperaturas de pirólise e atomização foram avaliadas por meio de curvas de pirólise e de atomização, respectivamente. Para suspensão de açúcar, temperaturas de pirólise e atomização (Tp, Ta) obtidas foram: sem modificador (400°C, 2000°C); Pd (1400°C, 2200°C); Pd/Mg (1400°C, 2200°C) e Ni (1600°C, 2200°C). Os valores para digeridos de açúcar foram: sem modificador (400°C, 2200°C); Pd (1400°C, 2200°C); Pd/Mg (1400°C, 2200°C) e Ni (600°C, 2200°C). Paládio foi selecionado como o melhor modificador químico. O tempo de vida do tubo de grafte foi de aproximadamente 350 queimas, o RSD (n = 12) para uma amostra típica contendo 5,52 µg As L-1 foi < 2,2% e o limite de detecção foi 2,4 pg As. Recuperações entre 80 e 92% foram encontradas.
Metrics
Article Details
This work is licensed under a Creative Commons Attribution 4.0 International License.
The corresponding author transfers the copyright of the submitted manuscript and all its versions to Eclet. Quim., after having the consent of all authors, which ceases if the manuscript is rejected or withdrawn during the review process.
When a published manuscript in EQJ is also published in other journal, it will be immediately withdrawn from EQ and the authors informed of the Editor decision.
Self-archive to institutional, thematic repositories or personal webpage is permitted just after publication. The articles published by Eclet. Quim. are licensed under the Creative Commons Attribution 4.0 International License.
References
BARRA, C. M.; SANTELLI, R. E.; ABRÃO, J. J.; DE LA GUARDIA, M. Especiação de arsênio - uma revisão. Quím. Nova, v.23, n.1, p.58-70, 2000. [ Links ]
BATLEY, G. E. Trace elements speciation: analytical methods and problems. Florida: CRC Press, 1989. 250p. [ Links ]
BRASIL, Portaria n. 685, 27 ago. 1998. Diário Oficial da União, Brasília, DF. [ Links ]
BUTCHER, D. J.; SNEDDON, J. A practical guide to graphite furnace atomic absorption spectrometry. New York: John Wiley & Sons, 1998. 250p. [ Links ]
CERVERA, M. L.; MONTORO, R. Critical review of the atomic spectrometric analysis of arsenic in food. Fresenius J. Anal. Chem., v.348, p.331-40, 1994. [ Links ]
CODEX alimentarius: general standard for contaminants and toxins in foods. 1998. p.45. [ Links ]
DABEKA, R. W.; MCKENZIE, A. D.; LACROIX, G. M. A.; CLEROUX, C.; BOWE, S.; GRAHAM, R. A.; CONACHER, H. B. S.; VERDIER, P. Survey of arsenic in total diet food composites and estimation of the dietary intake of arsenic by canadian adults and children. J. Assoc. Of Anal. Chem. Int., v.76, n.1, p.14-25, 1993. [ Links ]
EDIGER, R. D. Atomic absorption analysis with the graphite furnace using matrix modification. At. Absorpt. Newsl., v.14, n.5, p.127-30, 1975. [ Links ]
HARVEY, C. W. Referee's report general subject 2, ICUMSA, 1994. [ Links ]
International Commission for Uniform Methods of Sugar Analysis, 19., 1986, Canes. Proceedings... [ Links ]
International Commission for Uniform Methods of Sugar Analysis, 20., 1990, Colorado Springs. Proceedings... [ Links ]
KILDAHL, B. T.; LUND, W. Determination of arsenic and antimony in wine by ETAAS. Fresenius J. Anal. Chem., v.354, p.93-6, 1996. [ Links ]
KUBOTA, T.; YAMAGUCHI, T. ; OKUTANI, T. Determination of arsenic content in natural water by GFAAS after collection as molybdoarsenate on activated carbon. Talanta, v.46, p.1311-19, 1998. [ Links ]
LEBLEBICI, J.; VOLKAN, M. Preparation for arsenic, copper, iron and lead determination in sugar, J. Agric. Food Chem., v.46, p.173-77, 1998. [ Links ]
LIANG, L.; LAZOFF, S.; CHAN, C.; HORVAT, M.; WOODS, J. S. Determination of arsenic in ambient water at sub-part-per-trillion levels by hydride generation Pd coated platform collection and GFAAS detection. Talanta, v.47, p.569-83, 1998. [ Links ]
McKENZIE, H. A.; Smythe, L. E. (Ed.) Quantitative trace analysis of biological materials. New York: Elsevier, 1998, p.573-93. [ Links ]
NICHOLSON, J. W. Arsenic - the enigmatic element. Educ. Chem., v.29, n.1-6, p.101-3, 1992. [ Links ]
POZEBON, D.; DRESSLER, V. L.; GOMES NETO, J. A.; CURTIUS, A. J. Determination of arsenic (III) and arsenic (V) by ETAAS after complexation and sorption on a C-18 bonded silica column. Talanta, v.45, p.1167-75, 1998. [ Links ]
SANCHO, D.; VEGA, M.; DEBÁN, L.; PARDO, R.; GONZÁLEZ, G. Determination of copper and arsenic in refined beet sugar by stripping voltametry without sampre pretreatment. Analyst, v.123, p.743-47, 1998. [ Links ]
SANTA MARIA, I; GONZALES, M.; LARA, W.; OBER, A. Arsenic levels in chilean marine species. Bull. Environ. Contam. Toxicol., v. 37, n.4, p. 593-8, 1986. [ Links ]
SEILER, H. G.; SIGEL, H. Handbook on Toxicity of Inorganic Compounds, New York: Marcel Dekker, 1988, p.79-93. [ Links ]
SOARES, M. E.; BASTOS, M. L.; CARVALHO, F.; FERREIRA, M. Determination of As, Cd, and Pb in foodstuff by GFAAS. At. Spectrosc., v.16, n.4, p.149-153, 1995. [ Links ]
STYRIS, D. L.; PRELL, L. J. Mechanisms of palladium-induced stabilization of arsenic in electrothermal atomization atomic absorption spectroscopy. Anal. Chem., v.63, p.503-7, 1991. [ Links ]
TSALEV, D. L.; ZAPRIANOV, Z. K. AAS in Occupational and Environmental Health Practice, New York: CRC Press, 1983. p. 87-93. [ Links ]
VERCRUYSE, A. Hazardous metals in human toxicology. Amsterdam: Elsevier, 1984, p.199-223. [ Links ]
WELZ, B.; SCHLEMMER, G.; MUDAKAVI, J. R. Pd-nitrate Mg-nitrate modifie for ETAAS performance for the determination of 21 elements. J. Anal. At. Spectrom., v.7, p.1257-71, 1992. [ Links ]
XIO-QUAN, S.; ZHE-MING, N.; LI, Z. Determination of arsenic in soil, coal fly ash and biological samples by ETAAS with matrix modification. Anal. Chim. Acta, v.151, p.179-85, 1983. [ Links ]