Development of a label-free electrochemical aptasensor based on diazonium electrodeposition: Application to cadmium detection in water.
Anal Biochem
; 612: 113956, 2021 01 01.
Article
em En
| MEDLINE
| ID: mdl-32950496
ABSTRACT
In this study we have developed a new aptasensor for cadmium (Cd2+) detection in water. Gold electrode surface has been chemically modified by electrochemical reduction of diazonium salt (CMA) with carboxylic acid outward from the surface. This was used for amino-modified cadmium aptamer immobilization through carbodiimide reaction. Chemical surface modification was characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). This latter was also used for Cd2+ detection. The aptasensor has exhibited a good linear relationship between the logarithm of the Cd2+ concentration and the impedance changes in the range from 10-3 to 10-9 M with a correlation R2 of 0.9954. A high sensitivity was obtained with a low limit of detection (LOD) of 2.75*10-10 M. Moreover, the developed aptasensor showed a high selectivity towards Cd2+ when compared to other interferences such as Hg2+, Pb2+ and Zn2+. The developed aptasensor presents a simple and sensitive approach for Cd2+detection in aqueous solutions with application for trace Cd2+ detection in spring water samples.
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Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Cádmio
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Água
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Técnicas Biossensoriais
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Aptâmeros de Nucleotídeos
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Técnicas Eletroquímicas
Tipo de estudo:
Diagnostic_studies
Idioma:
En
Revista:
Anal Biochem
Ano de publicação:
2021
Tipo de documento:
Article