Dual-Mode Field-Deployable Platform Based on Self-Assembled Magnetic Probes for Simultaneous Monitoring of Chikungunya Virus and Host Immune Status.

Real-time dual monitoring of pathogen burden and host immune response enables risk stratification and precision therapy, yet remains technically challenging. Addressing the needs of chikungunya fever outbreak control, here, we developed a flexible, ultrasensitive dual-mode lateral flow immunoassay (LFA) capable of simultaneous detection of chikungunya virus (CHIKV) antigen and the inflammatory cytokine IL-6 across clinical samples. An enhanced colorimetric-fluorescent dual-signal magnetic probe (MAu2QD3) was synthesized via electrostatic self-assembly. By tuning the number of loaded signal layers (Au and CdSe/ZnS particles), the LFA platform achieved controllable adjustment of dual-signal output intensities. In parallel, an artificial intelligence-based dual-mode quantitative model was built to automatically integrate colorimetric and fluorescent readouts, yielding accurate target concentration estimates. In naked-eye mode, the assay exhibited visual limits of detection (LODs) of 50 pg·mL-1 for both CHIKV and IL-6. With portable instrument assistance, the colorimetric sensitivity of MAu2QD3-LFA increased by at least 4-fold, while fluorescent detection further reduced the LODs to 0.28 pg·mL-1 for CHIKV and 0.16 pg·mL-1 for IL-6. Validated using 91 clinical samples, the system achieved a sensitivity of 98.2% and a specificity of 100%, enabling reliable acquisition of both pathogen and host immune information. These results highlight strong potential for early surveillance and precise diagnosis of infectious diseases.