Appropriate carriers or templates are crucial for maintaining the stability, biological activity, and bioavailability of selenium nanoparticles (SeNPs). Selecting suitable templates remains challenging for fully utilizing SeNPs functionalities and developing applicable products. Exosome-like nanoparticles (ELNs) have gained importance in drug delivery systems, yet research on selenium products prepared using exosomes remains limited. To address this gap, we utilized Cyperus bean ELNs to deliver SeNPs, investigated three preparation methods for SeNPs-ELNs, identified the optimal approach, and performed characterization studies. Notably, all three methods successfully loaded SeNPs. Ultrasonic cell fragmentation is the optimal approach, achieving significant increases in selenium loading (5.59 ± 0.167 ng/μg), enlargement of particle size (431.17 ± 10.78 nm), and reduced absolute zeta potential (−4.1 ± 0.43 mV). Moreover, both exosome formulations demonstrated enhanced stability against aggregation during storage at 4 °C, while their stability varied with pH conditions. In vitro digestibility tests showed greater stability of SeNP-ELNs in digestive fluids compared to ELNs alone. Additionally, neither ELNs nor SeNP-ELNs exhibited cytotoxicity toward LO₂ cells, and the relative erythrocyte hemolysis remained below 5% at protein concentrations of 2.5, 7.5, 15, 30, and 60 μg/mL. Overall, ultrasonic cell fragmentation effectively loaded plant-derived exosomes with nano-selenium at high capacity, presenting new opportunities for their use as functional components in food and pharmaceutical applications.

Capsaicin, a natural bioactive compound, has attracted wide interest for its potential health benefits. However, its rapid metabolism and strong irritancy upon oral administration have greatly limited its further application. To address these issues, this study developed a nanoparticle delivery system using corn Zein and Brassica rapa L. polysaccharide (BP) as carriers, with capsaicin (CAP) as the core. The optimized formulation (BP:Zein = 1:2, Zein:CAP = 2.5:1, mg/mg) produced stable, uniform spherical nanoparticles with an average particle size of 203.05 nm, a polydispersity index (PDI) of 0.138, a zeta potential of −44.9 mV, an encapsulation efficiency of 54.03%, and a drug loading capacity of 184.57 μg/mg. Fourier transform infrared spectroscopy (FTIR), fluorescence spectroscopy (FS), X-Ray diffraction, scanning electron microscope (SEM), and transmission electron microscopy (TEM) analyses confirmed that CAP was successfully encapsulated, forming nanoparticles through hydrogen bonding and hydrophobic interactions between CAP and Zein. The obtained nanoparticles displayed regular spherical morphology and uniform size distribution. Compared with single-layer Zein–CAP nanoparticles, BP–Zein–Capsaicin (BZC) nanoparticles exhibited markedly improved stability under different pH, ionic strength, and storage conditions. In vitro simulated digestion showed a sustained-release profile, with 36.76% of CAP released after 4 h. The anti-inflammatory experiment showed that both the nanoparticle and free capsaicin groups significantly inhibited xylene-induced acute ear edema in mice, with the medium- and high-dose nanoparticle groups exhibiting stronger anti-inflammatory effects than the free capsaicin group. These findings suggest that the nanoparticle delivery system effectively enhances the anti-inflammatory activity of capsaicin, possibly by improving its stability, achieving sustained release, and enhancing its bioavailability in vivo. Overall, capsaicin-loaded Brassica rapa L. polysaccharide–Zein nanoparticles combine small particle size, high drug loading, and excellent stability, providing a promising strategy for functional food development and targeted bioactive delivery.