Jia Man,Luming Man,Chenchen Zhou,Jianyong Li,Shuaishuai Liang,Song Zhang,Jianfeng Li
Microfluidics devices have widely been employed to prepare monodispersed microbubbles/droplets, which have promising applications in biomedical engineering, biosensor detection, drug delivery, etc. However, the current reported microfluidic devices need to control at least two-phase fluids to make microbubbles/droplets. Additionally, it seems to be difficult to make monodispersed microbubbles from the ambient air using currently reported microfluidic structures. Here, we present a facile approach to making monodispersed microbubbles directly from the ambient air by driving single-phase fluid. The reported single-phase-fluid microfluidic (SPFM) device has a typical co-flow structure, while the adjacent space between the injection tube and the collection tube is open to the air. The flow condition inside the SPFM device was systematically studied. By adjusting the flow rate of the single-phase fluid, bubbles were generated, the sizes of which could be tuned precisely. This facile bubble generator may have significant potential as a detection sensor in detecting viruses in spread droplets or haze particles in ambient air.Keywords:microfluidic device;single-phase fluid;bubbles;air detection
Polycyclic aromatic hydrocarbons (PAHs) represent a class of carcinogenic, teratogenic, and mutagenic aromatic organic pollutants that are ubiquitous in the environment. The rapid and on-site detection of PAHs remains a challenge. This study proposes point-of-use (POU) surface-enhanced Raman spectroscopy (SERS)-based strategies for the qualitative and quantitative analyses of PAHs in environmental water and air. The results demonstrate clear correlations between the signal intensity and the logarithmic concentration of PAHs in water (ranging from 2.5 to 100 ppb), with satisfactory recovery and reproducibility. A similar trend was observed for PAHs on glass fiber filters modified with silver nanoparticles (AgNPs@GF filter). Specifically, the limits of detection (LOD) for fluoranthene, phenanthrene, and pyrene in water were 0.7, 1.0, and 0.1 ppb, respectively, while the LOD for fluoranthene, phenanthrene, and pyrene on the AgNPs@GF filter were 9.11, 18.18, and 14.59 ppb. Recovery rates in spiked real water and filters ranged from 83% to 126%, and the entire detection process was completed within 1 min. These findings highlight the significant potential of this method as a powerful tool for rapid on-site analysis of PAHs in various environmental matrices.
危险品化学品经营许可证（带存储）