Dual-aptamer magnetic capture and electrochemical detection of influenza B and respiratory syncytial viruses in artificial saliva
Analyst, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Basım Tarihi: 2026
- Doi Numarası: 10.1039/d6an01053a
- Dergi Adı: Analyst
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Chemical Abstracts Core, Chimica, Compendex, EMBASE, INSPEC, MEDLINE, Academic Search Ultimate (EBSCO)
- Ankara Üniversitesi Adresli: Evet
Özet
Saliva is a promising non-invasive specimen for respiratory virus diagnostics but its biochemical complexity challenges direct interfacing with affinity-based biosensors. We report a dual-aptamer magnetic-capture electrochemical assay for detection of influenza B virus (IBV) and human respiratory syncytial virus (hRSV) in artificial saliva. For each target virus, two sequence-distinct DNA aptamers are used: an amino-modified capture aptamer (IBV1 or RSV1) covalently coupled to ∼5 µm polydopamine-coated magnetic microparticles by direct Schiff-base reaction with the polydopamine quinone/catechol surface, and a thiol-modified detection aptamer (IBV2 or RSV2) self-assembled on screen-printed gold electrodes via thiol–gold chemistry. After a single multiplexed batch capture step with both aptamer–magnetic-particle types, the pellet is split and analysed in parallel on the two aptamer-modified electrodes by square-wave voltammetry (SWV). Langmuir analysis of the SWV calibration curves yielded apparent dissociation constants of Kd = 177 ± 62 PFU mL−1 (IBV) and 226 ± 85 PFU mL−1 (hRSV), with detection limits of 15 and 11 PFU mL−1, respectively. Log-linear calibration spanned 101–104 PFU mL−1 on both channels (n = 4 concentrations, R2 = 0.995 and 0.990) with sensitivities of 8.58 and 6.61 µA per decade, so that each virus-specific assay covers three orders of magnitude of viral load. The sequence-orthogonal dual-aptamer geometry—capture and detection recognitions targeting non-identical epitopes—is proposed as the structural mitigation. This proof-of-concept establishes a programmable, saliva-compatible architecture reconfigurable for emerging respiratory pathogens by aptamer substitution alone.