Sulfur-doped carbon dots@polydopamine-functionalized magnetic silver nanocubes for dual-modality detection of norovirus

• Published in: Biosensors & bioelectronics Vol. 193; p. 113540
• Main Authors: Achadu, Ojodomo J., Abe, Fuyuki, Hossain, Farzana, Nasrin, Fahmida, Yamazaki, Masahito, Suzuki, Tetsuro, Park, Enoch Y.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.12.2021
• Subjects: Carbon-dots; Dual-modality; Fluorescence-SERS; Immunocomplex; Magnetoplasmonic-Ag-nanocubes; Norovirus; Magnetoplasmonic-Ag-nanocubes; Immunocomplex; Dual-modality; Norovirus; Fluorescence-SERS; Carbon-dots
• ISSN: 0956-5663; 1873-4235
• DOI: 10.1016/j.bios.2021.113540

Synergistic dual-mode optical platforms are up-and-coming detection tools in the diagnosis and management of infectious diseases. Here, novel dual-modality fluorescence (FL) and surface-enhanced Raman scattering (SERS) techniques have been integrated into a single probe for the rapid and ultrasensitive detection of norovirus (NoV). The developed FL-SER-based biosensor relies on the dual-signal enhancements of newly synthesized sulfur-doped agar-derived carbon dots (S-agCDs). The antigen-antibody immunoreaction results in forming a core-satellite immunocomplex between anti-NoV antibody-conjugated S-agCDs and polydopamine-functionalized magnetic silver nanocubes [poly (dop)-MNPs-Ag NCs]. By deploying an immunomagnetic enrichment protocol and performing the SERS modality on a single-layer graphene substrate, norovirus-like particles (NoV-LPs) were detected across a wide range of 1 fg mL−1 – 10 ng mL−1 with an excellent limit of detection of 0.1 fg mL−1. The combined advantage of the dual-signaling properties of the biosensor was demonstrated using FL confocal imaging for “hotspots” tracking prior to SERS detection of clinical NoV in fecal specimen down to ⁓10 RNA copies mL−1. The proposed dual-modality biosensor's performance increases the prospect of a rapid and low-cost sensitive NoV detection and surveillance option for public health. [Display omitted] •A dual-modality biosensor based on Fluorescence and SERS techniques is presented for norovirus bioassay.•Magneto-plasmonic silver nanocubes served as the optical signal enhancer and magnetic enrichment materials.•Norovirus clinical specimens from infected patients were rapidly and ultrasensitively detected down to 10 RNA copies mL-1.