Spectrophotometric Determination of Zinc Using 7-(4-Nitrophenylazo)-8-Hydroxyquinoline-5-Sulfonic Acid



Document title: Spectrophotometric Determination of Zinc Using 7-(4-Nitrophenylazo)-8-Hydroxyquinoline-5-Sulfonic Acid
Journal: Journal of the Brazilian Chemical Society
Database: PERIÓDICA
System number: 000310858
ISSN: 0103-5053
Authors: 1


Institutions: 1Universidade Federal da Bahia, Instituto de Quimica, Salvador, Bahia. Brasil
Year:
Season: Ene
Volumen: 10
Number: 1
Pages: 46-50
Country: Brasil
Language: Inglés
Document type: Artículo
Approach: Experimental, aplicado
English abstract A sensitive and selective spectrophotometric method is proposed for the rapid determination of zinc(II) using an 8-hydroxyquinoline derivative, 7-(4-nitrophenylazo)-8-hydroxyquinoline-5-sulfonic acid (p-NIAZOXS), as a new spectrophotometric reagent. The reaction between the p-NIAZOXS and zinc(II) is instantaneous at pH 9.2 (borax buffer) and the absorbance remains stable for over 24 h. The method allows the determination of zinc over the range of 0.05-1.0 mug mL-1 with a molar absorptivity of 3.75x10(4) L mol-1 cm-1 and features a detection limit of 15 ng mL-1. The proposed method has been successfully applied to the determination of zinc in several pharmaceutical preparations and copper alloys. The precision (R.S.D. < 2%) and the accuracy obtained were satisfactory
Portuguese abstract Um novo método espectrofotométrico para determinação de zinco(II) é proposto usando um derivado da 8-hidroxiquinolina, o ácido 7-(4-nitrofenilazo)-8-hidroxiquinolina sulfônico (p-NIAZOXS). A reação entre o p-NIAZOXS e o zinco(II) é rapida em pH 9,2 e o complexo formado é estável por pelo menos 24 h. O método permite a determinação de zinco na faixa de 0,05 a 1,0 mig mL-1 com absortividade molar de 3,75 x 10(4) L mol-1 cm-1 e limite de detecção de 15 ng mL-1. O método proposto foi aplicado na determinação de zinco em produtos farmacêuticos e ligas de cobre, onde a precisão (R. S. D. < 2%) e exatidão obtidas foram satisfatórias
Disciplines: Química
Keyword: Química analítica,
Zinc,
Determinación espectrofotométrica,
Acido 7-(4-nitrofenilazo)-8-hidroxiquinolin-5-sulfónico
Keyword: Chemistry,
Analytical chemistry,
Zinc,
Spectrophotometric determination,
7-(4-nitrophenylazo)-8-hydroxyquinoline-5-sulphonic acid
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