Plant-derived extracellular vesicles quality control: key process progress and future research directions​

Plant-derived extracellular vesicles (PDEVs) have garnered significant attention as crucial mediators of intercellular and cross-species communication in plants, owing to their unique bioactivity and medicinal potential. However, quality control of PDEVs is of paramount importance for their functionality and applications. This review systematically summarizes the key aspects that influence PDEVs quality, including source material preparation, isolation and purification, characterization, and storage conditions. Regarding source material preparation, the genetic background, abiotic factors (such as light, temperature, and moisture), biotic factors (including pathogen infection and probiotic effects), and traditional processing methods significantly affect the composition and function of PDEVs. Plant tissue culture techniques and temporary immersion bioreactor systems (TIBS) have substantial potential for addressing the issue of fluctuating raw material quality. During the isolation and purification processes, existing methods (e.g., ultracentrifugation, polymer precipitation, and size-exclusion chromatography) have their respective advantages and disadvantages, necessitating the optimization of operations based on specific requirements to avoid vesicle damage or impurity introduction. In terms of characterisation, integrating techniques such as transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA), and western blotting can comprehensively evaluate the quality of PDEVs. Additionally, storage conditions significantly affect the stability of PDEVs, and appropriate measures should be adopted to reduce degradation. Future research should focus on developing standardized preparation processes and efficient characterization techniques to facilitate the widespread application of PDEVs in drug delivery, functional foods, and other fields.