Signal enhancement on gold nanoparticle-based lateral flow tests using cellulose nanofibers

Lateral flow paper-based biosensors merge as powerful tools in point-of-care diagnostics since they are cheap, portable, robust, selective, fast and easy to use. However, the sensitivity of this type of biosensors is not always as high as required, often not permitting a clear quantification. To imp...

Descripción completa

Detalles Bibliográficos
Autores: Quesada-González, Daniel|||0000-0003-3064-2146, Stefani, Christina|||0000-0002-8818-075X, González Tovar, Israel|||0000-0002-3031-4516, De La Escosura-Muñiz, Alfredo|||0000-0002-9600-0253, Domingo Marimon, Neus|||0000-0002-5229-6638, Mutjé, Pere|||0000-0001-8211-4949, Merkoçi, Arben|||0000-0003-2486-8085
Tipo de recurso: artículo
Fecha de publicación:2019
País:España
Institución:Universitat Autònoma de Barcelona
Repositorio:Dipòsit Digital de Documents de la UAB
Idioma:inglés
OAI Identifier:oai:ddd.uab.cat:218082
Acceso en línea:https://ddd.uab.cat/record/218082
https://dx.doi.org/urn:doi:10.1016/j.bios.2019.111407
Access Level:acceso abierto
Palabra clave:Lateral flow
Biosensor
Cellulose
Gold nanoparticles
Nanofibers
Descripción
Sumario:Lateral flow paper-based biosensors merge as powerful tools in point-of-care diagnostics since they are cheap, portable, robust, selective, fast and easy to use. However, the sensitivity of this type of biosensors is not always as high as required, often not permitting a clear quantification. To improve the colorimetric response of standard lateral flow strips (LFs), we have applied a new enhancement strategy that increases the sensitivity of LFs based on the use of cellulose nanofibers (CNF). CNF penetrate inside the pores of LFs nitrocellulose paper, compacting the pore size only in the test line, particularly near the surface of the strip. This modification retains the bioreceptors (antibodies) close to the surface of the strips, and thus further increasing the density of selectively attached gold nanoparticles (AuNPs) in the top part of the membrane, in the test line area, only when the sample is positive. This effect boosts in average a 36.6% the sensitivity of the LFs. The optical measurements of the LFs were carried out with a mobile phone camera whose imaging resolution was improved by attaching microscopic lens on the camera objective. The characterization of CNF into paper and their effect was analyzed using atomic force microscope (AFM) and scanning electron microscope (SEM) imaging techniques.