Cargando…

Protein detection enabled using functionalised silk-binding peptides on a silk-coated optical fibre

We present a new coating procedure to prepare optical fibre sensors suitable for use with protein analytes. We demonstrate this through the detection of AlexaFluor-532 tagged streptavidin by its binding to D-biotin that is functionalised onto an optical fibre, via incorporation in a silk fibroin fib...

Descripción completa

Detalles Bibliográficos
Autores principales: Capon, Patrick K., Horsfall, Aimee J., Li, Jiawen, Schartner, Erik P., Khalid, Asma, Purdey, Malcolm S., McLaughlin, Robert A., Abell, Andrew D.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: The Royal Society of Chemistry 2021
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9034238/
https://www.ncbi.nlm.nih.gov/pubmed/35480827
http://dx.doi.org/10.1039/d1ra03584c
Descripción
Sumario:We present a new coating procedure to prepare optical fibre sensors suitable for use with protein analytes. We demonstrate this through the detection of AlexaFluor-532 tagged streptavidin by its binding to D-biotin that is functionalised onto an optical fibre, via incorporation in a silk fibroin fibre coating. The D-biotin was covalently attached to a silk-binding peptide to provide SBP–biotin, which adheres the D-biotin to the silk-coated fibre tip. These optical fibre probes were prepared by two methods. The first involves dip-coating the fibre tip into a mixture of silk fibroin and SBP–biotin, which distributes the SBP–biotin throughout the silk coating (method A). The second method uses two steps, where the fibre is first dip-coated in silk only, then SBP–biotin added in a second dip-coating step. This isolates SBP–biotin to the outer surface of the silk layer (method B). A series of fluorescence measurements revealed that only the surface bound SBP–biotin detects streptavidin with a detection limit of 15 μg mL(−1). The fibre coatings are stable to repeated washing and long-term exposure to water. Formation of silk coatings on fibres using commercial aqueous silk fibroin was found to be inhibited by a lithium concentration of 200 ppm, as determined by atomic absorption spectroscopy. This was reduced to less than 20 ppm by dialysis against water, and was found to successfully form a coating on optical fibres.