title: Fast analysis of terbutaline in pharmaceuticals using multi-walled nanotubes modified electrodes from recordable compact disc.
abstract: In this study, homemade disposable gold electrodes made from recordable compact disks were modified with carbon nanotubes for amperometric quantification of terbutaline sulfate in pharmaceutical products. A flow cell using an impingent jet of solution on the electrode surface was build and used for amperometric detection, and a series of experiments were carried out to find the best experimental conditions for the new electrode in a specially designed cell. A linear response for terbutaline was obtained in the range from 3.0 × 10(-6) to 5.0 × 10(-4) mol L(-1) (at 0.63 V vs. Ag/AgCl). The limits of detection and quantification were calculated as 5.8 × 10(-7) mol L(-1) (S/N = 3) and 1.9 × 10(-6) mol L(-1) (S/N = 10), respectively. A frequency of 30 injections h(-1) was attained. The proposed method was successfully applied to the analyses of commercial syrup samples, and all results were in good agreement with those obtained by using high performance liquid chromatography and capillary electrophoresis-tandem mass spectrometry.
authors.affiliation: Universidade de São Paulo, Instituto de Química, São Paulo, 05508-000, Brazil.
authors.forename: Fabiana S
authors.initials: FS
authors.lastname: Felix
authors.affiliation: Universidade de São Paulo, Instituto de Química, São Paulo, 05508-000, Brazil; Agilent Technologies, Alameda Araguaia, 1142, CEP 06455-000, Barueri, SP, Brazil.
authors.forename: Daniela
authors.initials: D
authors.lastname: Daniel
authors.affiliation: Universidade de São Paulo, Instituto de Química, São Paulo, 05508-000, Brazil.
authors.forename: Jivaldo R
authors.initials: JR
authors.lastname: Matos
authors.affiliation: Universidade de São Paulo, Instituto de Química, São Paulo, 05508-000, Brazil.
authors.forename: Claudimir
authors.initials: C
authors.lastname: Lucio do Lago
authors.affiliation: Universidade de São Paulo, Instituto de Química, São Paulo, 05508-000, Brazil. Electronic address: luangnes@iq.usp.br.
authors.forename: Lúcio
authors.initials: L
authors.lastname: Angnes
mesh_terms: D016250:Compact Disks; D004563:Electrochemistry / Q000295:instrumentation*; D004566:Electrodes; D006046:Gold / Q000737:chemistry; D057230:Limit of Detection; D037742:Nanotubes, Carbon / Q000737:chemistry*; D004364:Pharmaceutical Preparations / Q000737:chemistry*; D013726:Terbutaline / Q000032:analysis* / Q000737:chemistry; D013997:Time Factors
chemical_list: D037742:Nanotubes, Carbon; D004364:Pharmaceutical Preparations; D006046:Gold; D013726:Terbutaline
keywords: Amperometry; Gold electrodes from recordable compact disc; Impingent flowing system; Multi-walled nanotubes; Terbutaline