A bare-eye based one-step signal amplified semiquantitative immunochromatographic assay for the detection of imidacloprid in Chinese cabbage samples.
Anal Chim Acta
; 881: 82-9, 2015 Jun 30.
Article
em En
| MEDLINE
| ID: mdl-26041523
ABSTRACT
A novel bare-eye based one-step signal amplified semi-quantitative immunochromatographic assay (SAS-ICA) was developed for detection of the pesticide imidacloprid. This method was based on competitive immunoreactions. Signal amplification was achieved by dual labeling of the test lines (TLs) on the strip using high affinity nanogold-biotinylated anti-imidacloprid mAb (BAb) and nanogold-streptavidin (Sa) probes. The relative color intensities of three TLs (TL-I, TL-II and TL-III) on a nitrocellulose (NC) membrane were used for direct visual analysis of the SAS-ICA strips, and could be used for semi-quantitation of analyte concentrations by observing what TLs disappeared in the amplification zone. Under optimized conditions, the following imidacloprid concentration ranges would be detected by visual examination of the SAS-ICA strip 0-5ngmL(-1) (negative samples), and 5-25ngmL(-1), 25-250ngmL(-1), 250-1000ngmL(-1) and >1000ngmL(-1) (positive samples). The sensitivity (the visual detection limit (VDL) of TL-III) and semi-quantitative analytical capacity (when TL-III disappeared completely) of the SAS-ICA strip were 10-fold and 160-fold higher than those of traditional ICA, respectively. The developed SAS-ICA strip was applied to the analysis of spiked and authentic contaminated Chinese cabbage samples in the laboratory and under field conditions, and the results were validated by high-performance liquid chromatography (HPLC). This process could be adopted as a potential generous technique for all ICA-based detection methods.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Brassica
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Resíduos de Praguicidas
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Técnicas Biossensoriais
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Contaminação de Alimentos
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Cromatografia de Afinidade
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Imidazóis
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Nitrocompostos
Tipo de estudo:
Diagnostic_studies
Idioma:
En
Revista:
Anal Chim Acta
Ano de publicação:
2015
Tipo de documento:
Article