Field-deployable aptasensor with automated analysis of stain patterns for the detection of chlorpyrifos in water.
Talanta
; 252: 123782, 2023 Jan 15.
Article
em En
| MEDLINE
| ID: mdl-36029684
Organophosphorus compounds such as chlorpyrifos (CPS) are causing serious environmental problems worldwide. Efficient monitoring of the CPS levels in water resources demands portable devices for on-field testing. Here we report the development of a CPS sensor coupled with smartphones for automated reading and data analysis. The sensing mechanism makes use of gold nanoparticles stabilized by a CPS-specific aptamer, where colloidal destabilization occurs in presence of competing CPS molecules. In particular, an innovative readout is proposed: quantitative analysis of the stain patterns left by evaporating drops of the test solutions. We have found that the CPS-induced destabilization suppresses the typical coffee-ring stain of the colloidal gold, and then exploited the phenomenon to quantitatively determine the CPS concentration in water samples. A strong correlation between CPS level in samples and the alteration of the stain patterns was established for a wide range of CPS concentrations (0.048 µM-482 µM). The limit of detection of the sensor was 0.2 µM. The assay was implemented on Whatman filter paper cards that were specially patterned by wax-printing. A smartphone-based Python program was written for fully automated image capture and processing. Notably, as we analyze the spatial configuration of the stains, the reading system is independent of external illumination. The system also enables data management and traceability, which are highly desirable attributes for environmental monitoring.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Técnicas Biossensoriais
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Clorpirifos
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Aptâmeros de Nucleotídeos
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Nanopartículas Metálicas
Idioma:
En
Revista:
Talanta
Ano de publicação:
2023
Tipo de documento:
Article
País de afiliação:
Argentina
País de publicação:
Holanda