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The analytical performance of non-chromatographic coupled hydride generation, integrated atom trap (HG-IAT) atomizer flame absorption spectrometry (FAAS) systems were evaluated for the speciation analysis of antimony in environmental samples. Antimony, using formation of stibine (SbH 3 ) vapors were atomized in an air-acetylene flame-heated IAT. A new design of HG-IAT-FAAS hyphenated technique that would exceed the operational capabilities of existing arrangements (a water-cooled single silica tube, double-slotted quartz tube or an ''integrated trap'') was investigated. For the estimation of Sb(III) and Sb(V) concentrations in samples, the difference between the analytical sensitivities of the absorbance signals obtained for antimony hydride without and with previous treatment of samples with L-cysteine can be used. The concentration of Sb(V) was calculated by the difference between total Sb tot and Sb(III). A dramatic improvement in detection limit was achieved compared with that obtained using either of the atom trapping techniques, presented above, separately. This novel approach decreases the detection limit down to low pg mL À1 levels. The concentration detection limit, defined as 3 times the blank standard deviation (3sigma), was 0.2 ng mL À1 . For a 120 s in situ pre-concentration time (sample volume of 2 mL), sensitivity enhancement compared to flame AAS, was 550 fold for Sb, using hydride generation-atom trapping technique. The sensitivity can be further improved by increasing the collection time. The precision, expressed by RSD, was 8.0% (n = 6) for Sb. The designs studied include slotted tube, water-cooled single silica tube and integrated atom traps. Reference and real sample materials were analyzed. The accuracy of the method was verified by the use of certified reference materials (NIST SRM 2704 Buffalo River Sediment, SRM 2710 Montana Soil, SRM 1633a Coal Fly Ash, SRM 1575 Pine Needles, SRM 1643e Trace Elements in Water) and by aqueous standard calibration technique (solutions). The measured Sb content, in reference materials, were in satisfactory agreement with the certified values. The hyphenated technique was applied for antimony determinations in soil, sediment, coal fly ash, sewage and river water.

O desempenho analítico do acoplamento de geração de hidretos com sistema de aprisionamento de átomos (HG-IAT) em espectrometria de absorção atômica com chama (FAAS) foi avaliado para determinação de In e Tl em material de referência. Hidretos de índio (InH 3) e tálio (TlH) foram atomizados em sistema IAT aquecido em chama ar-acetileno. Investigou-se um novo arranjo da técnica hifenizada HG-IAT-FAAS, que superaria a capacidade operacional dos arranjos existentes (tubo de sílica resfriado com água, tubo de quartzo com dupla fenda ou "aprisionamento integrado"). Obteve-se significativa melhora nos limites de detecção, em relação às técnicas de aprisionamento de átomos acima citadas. Os limites de detecção, definidos como 3 vezes o desvio padrão do branco (3σ), foram 0,60 e 0,40 ng mL-1 para In e Tl, respectivamente. Para um tempo de pré-concentração de 120 s in situ (volume da amostra de 2 mL), a melhora na sensibilidade, comparando-se com espectrometria de absorção atômica com chama foi de 417 e 450 para In e Tl, respectivamente, usando a técnica de geração de hidretos e aprisionamento de átomos. A sensibilidade pode ser ainda melhorada aumentando-se o tempo de coleta. A precisão, expressa por RSD, foi de 4,4% e 5,2% (n = 6) para In e Tl, respectivamente. Os arranjos estudados incluíram tubo com fenda, tubo simples de sílica e aprisionamento de átomos resfriado e integrado. A precisão e exatidão do método foram verificadas pelo uso do material de referência certificado (GBW 07302 Sedimento) e soluções analíticas de calibração em meio aquoso. Os teores de In e Tl determinados no material de referência apresentaram adequada concordância com os valores certificados ou indicativos. The analytical performance of coupled hydride generation-integrated atom trap (HG-IAT) atomizer flame atomic absorption spectrometry (FAAS) system was evaluated for determination of In and Tl in reference material. Indium, using formation of InH 3 and TlH vapors were atomized in air-acetylene flame-heated IAT. A new design of HG-IAT-FAAS hyphenated technique that would exceed the operational capabilities of existing arrangements (a water-cooled single silica tube, double-slotted quartz tube or an "integrated trap") was investigated. A dramatic improvement in detection limits was achieved compared with that obtained using either of the atom trapping techniques, presented above, separately. The detection limits, defined as 3 times the blank standard deviation (3σ), were 0.60 and 0.40 ng mL-1 for In and Tl, respectively. For a 120 s in situ preconcentration time (sample volume of 2 mL), sensitivity enhancement compared to flame AAS, were 417 and 450 folds for In and Tl, respectively, using hydride generation-atom trapping technique. The sensitivity can be further improved by increasing the collection time. The precision, expressed by RSD, was 4.4% and 5.2% (n = 6) for In and Tl, respectively. The designs studied included slotted tube, single silica tube and integrated atom trap-cooled atom traps. The accuracy of the method was verified by the u...

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