Research Spectrum: Advances in Biosensors

Origins of Atlantic Salmon (Salmo salar) Determined Using a Hybridization Assay of Mitochondrial DNA on a Microfluidic Biochip

Lin Wang — 2026-08-20

A hybridization assay based on the microfluidic biochip was developed to identify the origin of the Atlantic salmon species. Among the 215 single nucleotide polymorphic (SNP) sites found in the mtDNA of Salmo salar, we located five sites in devising our assay method. We found two sites that worked, while the others generated either insufficient signals or specificity. We have successfully identified the North American origin of the three samples, as confirmed by Sanger sequencing.

All-LCP Terahertz Metasensor with Dual Quasi-BIC Resonances for Dual-Range Refractive Index Sensing

Yan Zhang — 2026-08-19

Terahertz (THz) metasurface biosensors still encounter difficulties in simultaneously achieving high spectral resolution and stable readout across different refractive-index regimes. In this work, an all-liquid-crystal-polymer (LCP) THz metasensor supporting dual quasibound states in the continuum (quasi-BIC) resonances is proposed for regime-dependent refractive-index sensing. By introducing structural asymmetry into a periodic LCP cubic-cluster metasurface, two pronounced resonances are generated with quality factors (Q factors) of 6811 and 2526, respectively. Near-field distributions and multipole decomposition analysis indicate that the two resonances possess distinct electromagnetic features, which result in different responses to surrounding dielectric perturbations. In the lowrefractive-index range of 1.0–1.5, the two resonance frequencies exhibit a linear variation with refractive index, yielding sensitivities of 122 GHz/RIU and 179 GHz/RIU, respectively. These dual-mode linear responses further offer a foundation for concentration- and temperature-related evaluation through analyte refractive-index mapping. In the higher-refractive-index range of 1.5–1.8, the intermodal frequency difference shows improved linearity with refractive index compared with the individual resonance frequencies, enabling a differential readout scheme with enhanced robustness against common perturbations. The results demonstrate that the proposed all-LCP dual-quasi-BIC metasensor not only enables high-resolution THz refractive-index sensing, but also establishes a regime-dependent spectral readout approach for different dielectric-response intervals.

Biosensor-Integrated Microneedle Devices for Diagnosis and Treatment of Chronic and Infectious Diseases: Current Status, Trends and Challenges

Mohamed M. Ashour — 2026-05-21

Despite advancements in clinical diagnostics, traditional biomarker detection methods (e.g., ELISA) remain limited due to their invasive nature, slow results, and inadequate use for continuous monitoring in low-resource settings. With the rise in chronic, infectious, and metabolic diseases, there is a pressing demand for real-time, minimally invasive diagnostic tools. Nanoengineered microneedle (MN) biosensors offer a promising solution. These painless devices can access interstitial fluid (ISF), a rich source of biomarkers, while utilizing advanced nanomaterials for high sensitivity and multiplexed detection. When combined with AI, IoT connectivity, and cloud-based analytics, MN biosensors enable personalized health data and continuous disease management. This review outlines recent advances in MN technology, including innovations in design and nanomaterial integration, as well as translational challenges like manufacturing scalability and regulatory approval. We explore how MN designs incorporating various sensing modalities can facilitate real-time monitoring of biomarkers such as glucose, lactate, and inflammatory proteins. Importantly, we discuss how these devices can improve healthcare access, reduce costs, and empower patients through everyday monitoring. This review integrates developments in MN engineering with biosensing and therapeutics, positioning biosensor-integrated MNs as pivotal in enabling continuous, minimally invasive disease monitoring and personalized therapy beyond traditional hospital environments.

Size Enlargement Enabled Functional Profiling of Extracellular Vesicle at Single-Particle Level

Jia Yao — 2026-08-19

Extracellular vesicles (EVs) are promising biomarkers for liquid biopsy, but their clinical application is limited by intrinsic heterogeneity and the lack of methods capable of resolving functionally distinct EV subpopulations at the single-vesicle level. Conventional bulk analyses obscure rare but clinically relevant EV subsets, while most single-EV approaches focus on physical properties or surface markers, with limited access to intravesicular functional information. Here, we report a fusion-enabled EV detection strategy at the single-particle level for functional profiling of macrophage-derived EVs. Liposomal probes encapsulating L-arginine, NADPH, and a nitric oxide (NO)-responsive fluorescent dye are engineered to fuse with EV membranes, delivering substrates into the vesicle lumen. In macrophage-derived EVs, inducible nitric oxide synthase (iNOS) catalyzes NO production, activating the fluorescent probe and generating a localized signal within individual vesicles. Signal generation is confined to vesicle-restricted reactions, ensuring specificity and minimizing background. The formation of hybrid vesicles further facilitates optical detection using conventional fluorescence microscopy.

Efficient On-Chip Separation and Labeling of Extracellular Vesicles from Whole Blood

Jian Feng — 2026-08-19

The development of high-throughput technologies for the separation and labeling of extracellular vesicles (EVs) from whole blood is critical for downstream EV detection and analysis. However, conventional EV separation and labeling workflows are typically labor-intensive and inefficient, requiring multiple sequential processing steps. Here, we present a microfluidic platform that integrates negative magnetophoresis-based separation with mixing-enhanced on-chip labeling. The chip adopts a vertical flow channel architecture in combination with a Halbach-array magnetic field configuration, thereby overcoming the throughput limitations inherent to traditional horizontal microchannels. Parallel channels can be freely arranged above on the magnetic array to achieve ultra-high throughput processing, achieving a cell removal efficiency of 99.97% at a blood-to-sheath flow ratio of 1:5. Furthermore, by incorporating a narrow-wide channel design synergized with a herringbone–Tesla micromixer structure, the platform achieves a labeling efficiency of 91.8% within 2 min, approaching the performance of conventional 20 min incubation. This system offers both high-throughput and integration capabilities, providing a powerful technical platform for EV-related life science research.