High shear vortex fluidics coupled with NIR affords luminescent carbon dots as a scalable process.

The fabrication of hybrid protein-Cu3(PO4)2 nanoflowers (NFs) via an intermediate toroidal structure is dramatically accelerated under shear using a vortex fluidic device (VFD) which possesses a rapidly rotating angled tube. As-prepared laccase NFs (LNFs) exhibit ≈1.8-fold increase in catalytic activity compared to free laccase under diffusion control, which is further enhanced by ≈2.9-fold for the catalysis under shear in the VFD. A new LNF immobilization platform (VLIS) was subsequently developed by mixing the LNFs for 15 min with silica hydrogel resulting in gelation along the VFD tube surface. The resultant LNFs@Silica coating is highly stable and reusable, which allows a dramatic 16-fold enhancement in catalytic rates relative to LNF@Silica inside glass vials. Real-time monitoring of the UV-Vis within the LNFs@Silica coated tube reveals good stability of the coating in continuous flow processing. The results demonstrate the utility of the VFD microfluidic platform, further highlighting its ability in controlling chemical and enzymatic processes.

Macroporous bovine serum albumin (BSA) nanoparticles with controllable diameter were readily fabricated in a rapidly rotating angled glass tube in a vortex fluidic device (VFD). Systematically varying the rotational speed and the ratio of BSA, ethanol, and glutaraldehyde led to conditions for generating ca. 600 nm diameter macroporous particles that have intrinsic fluorescence emission at 520 nm when excited at 490 nm. The presence of the macropores increased the absorption efficiency of rhodamine B with potential applications for drug delivery purpose, compared with BSA nanoparticles having surfaces devoid of pores. Further control over the size of BSA nanoparticles occurred in the presence of C-phycocyanin protein during the VFD processing, along with control of their shape, from spheres to pockets, as established in exploring the parameter space of the microfluidic device.

Selective formation of only one iron oxide phase is a major challenge in conventional laser ablation process, as is scaling up the process. Herein, superparamagnetic single-phase magnetite nanoparticles of hexagonal and spheroidal-shape, with an average size of ca. 15 nm, are generated by laser ablation of bulk iron metal at 1064 nm in a vortex fluidic device (VFD). This is a one-step continuous flow process, in air at ambient pressure, with in situ uptake of the nanoparticles in the dynamic thin film of water in the VFD. The process minimizes the generation of waste by avoiding the need for any chemicals or surfactants and avoids time-consuming purification steps in reducing any negative impact of the processing on the environment.