Lab on a Chip最新文献

Hydrodynamic dispersion of solutes is a pivotal phenomenon in microfluidic systems, wherein the axial spreading of various dissolved species-including ions, chemical compounds, biomolecules, dyes, pharmaceuticals, and nanoparticles-occurs due to the coupled effects of molecular diffusion and the non-uniform velocity profiles inherent to confined laminar flows. Given its profound impact on a broad range of applications-spanning analytical, diagnostic, bioengineering, pharmaceutical, environmental, and chemical processing systems-mastering the mechanisms of dispersion is crucial for enhancing separation efficiency, reproducibility, reaction performance, and analytical throughput, while minimizing sample volume, energy consumption, and undesired side effects. This comprehensive review provides a structured synthesis of the fundamental concepts, historical development, and governing mechanisms underlying Taylor-Aris dispersion in micro- and nanofluidic systems. Special emphasis is placed on the role of flow profile design, channel cross-sectional geometry, and surface physicochemical properties in modulating dispersion intensity. Through a systematic analysis of analytical, numerical, and experimental studies conducted from 2000 to 2025, we identify prevailing challenges, unresolved questions, and methodological gaps in the literature. Notably, this work addresses a key void by offering the first coherent classification that concurrently explores the mechanistic origins and engineering control strategies of hydrodynamic dispersion across diverse operating regimes. By bridging classical theories with emerging microfluidic architectures, this article not only deepens the understanding of dispersion phenomena but also lays the foundation for future innovations in colloid and interface science. As such, it provides an essential resource for researchers aiming to optimize transport, separation, and energy conversion processes in advanced fluidic systems.

Although microfluidic-based nanoprecipitation represents a powerful approach for the reproducible fabrication of various nanosized drug carrier systems, industrial translation remains limited. While versatile chip designs implementing advanced mixing elements exist, analytical tools for elucidating the precipitation mechanism, identifying critical process parameters, and monitoring carrier formation within the chip are sparse. Conventional characterization methods used for micromixers, such as tracing fluorescent dyes and/or computational fluid dynamics simulations, provide mostly indirect, often only two-dimensional insight, limiting their predictive value for scale-up and regulatory translation. In this study, a novel toolset combining confocal Raman and confocal fluorescence microscopy, as well as Foerster resonance energy transfer microscopy, was established to monitor solvent fluid dynamics and the in situ self-assembly of liposomes under varying flow conditions within a serpentine micromixer. This integrative approach enabled real-time spatial resolution of nanocarrier formation within the microfluidic device, confirming that vesicle formation predominantly occurs at the interface between the aqueous and ethanolic phases, underscoring the robustness of the setup. Beyond advancing mechanistic insight, the complementary use of two confocal microscopy techniques and a Foerster resonance energy transfer-based method offers a powerful toolset for process optimization and in-process quality control. Coupled with advances in additive manufacturing, this approach paves the way for rational micromixer design and the scalable production of microfluidic nanocarrier-based therapeutics, overcoming limitations and accelerating the industrial large-scale production of nanosized therapeutics.

The diagnosis of heart failure in emergency settings requires rapid and sensitive detection of brain natriuretic peptide (BNP), a low-abundance biomarker of heart failure with a clinical rule-out threshold of 100 pg mL⁻¹ (0.03 nM). The current gold standards for BNP testing in clinical practice all rely on immunoassays that necessitate cold-chain storage for antibodies, limiting their utility at the point-of-care. We now propose an enzyme-free, isothermal amplification strategy employing a dual-aptamer system to measure BNP at clinically relevant levels. Upon simultaneous binding to the target BNP, both of the aptamers release their complementary DNAs, consequently triggering a cyclic amplification reaction. The resulting secondary DNA structures can be detected via a lateral flow test (LFT) format, providing visual readouts close to the patient in 30 min at room temperature. This work advances the field by combining the specificity of aptamers with the simplicity of LFTs, offering the sensitivity of conventional immunoassays while eliminating any enzymatic steps. This work bridges the gap between lab-based immunoassays and POC needs, offering a reliable, equipment-free alternative for heart failure diagnosis in resource-limited settings. Future studies will validate its performance with blood samples for clinical deployment.