Engineering Plant-Derived Exosome-like Nanoparticles as Bioinspired Nanocarriers: From Physicochemical Properties to Tumor Delivery Performance

Plant-derived exosome-like nanoparticles (PELNs) are lipid bilayer nanostructures containing endogenous lipids, proteins, nucleic acids, and phytochemicals, which have attracted increasing interest as bioinspired carriers for cancer therapy. This review evaluates how plant source, isolation, purification procedures, vesicle composition, cargo-loading strategy, and administration route shape the quality and tumor-delivery performance of PELNs. The available evidence indicates that plant source and processing are major determinants of particle size, purity, surface charge, cargo profile, and biological activity. Ultracentrifugation remains widely used but is limited by contaminant co-isolation and poor scalability, whereas density-gradient purification and size-exclusion chromatography improve purity, and ultrafiltration and tangential flow filtration offer greater potential for large-scale manufacturing. Passive incubation generally preserves vesicle integrity and is most suitable for hydrophobic small molecules, whereas electroporation, sonication, and extrusion can increase cargo loading but may cause aggregation, membrane remodeling, or loss of endogenous components. Preclinical studies suggest that PELNs can exert intrinsic antitumor effects, modulate the tumor microenvironment, improve chemotherapeutic delivery, and help overcome drug resistance. However, evidence for in vivo tumor-targeting remains less robust than evidence for cellular uptake, and direct comparisons with established nanocarriers remain scarce. Clinical translation will require standardized nomenclature and characterization, reproducible manufacturing, quantitative loading and release assays, route-specific biodistribution studies, and repeated-dose safety evaluation. These findings provide a framework for the rational development of PELNs as reproducible tumor-oriented nanocarriers.