Electrochemical immunosensor for ethinylestradiol using diazonium salt grafting onto silver nanoparticles-silica-graphene oxide hybrids.
Talanta
; 147: 328-34, 2016 Jan 15.
Article
em En
| MEDLINE
| ID: mdl-26592615
This work describes the preparation of an electrochemical immunosensor for ethinylestradiol (EE2) based on grafting of diazonium salt of 4-aminobenzoic acid onto a glassy carbon electrode modified with silver nanoparticles/SiO2/graphene oxide hybrid followed by covalent binding of anti-ethinylestradiol (anti-EE2) to activated carboxyl groups. A competitive immunoassay was developed for the determination of the hormone using peroxidase-labeled ethinylestradiol (HRP-EE2) and measurement of the amperometric response at -200mV in the presence of hydroquinone (HQ) as redox mediator. The calibration curve for EE2 exhibited a linear range between 0.1 and 50ng/mL (r(2)=0.996), with a detection limit of 65pg/mL. Interference studies with other hormones related with EE2 revealed the practical specificity of the developed method for the analyte. A good reproducibility, with RSD=4.5% (n=10) was also observed. The operating stability of a single bioelectrode modified with anti-EE2 was maintained at least for 15 days when it was stored at 4°C under humid conditions between measurements. The developed immunosensor was applied to the analysis of spiked urine with good results.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Prata
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Imunoensaio
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Técnicas Biossensoriais
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Dióxido de Silício
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Compostos de Diazônio
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Etinilestradiol
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Grafite
Limite:
Humans
Idioma:
En
Revista:
Talanta
Ano de publicação:
2016
Tipo de documento:
Article
País de afiliação:
Brasil
País de publicação:
Holanda