Milk‑derived exosomes: optimized extraction strategies, proteomic characterization, stability, and biomedical applications

Abstract

Background. Exosomes are nanoscale vesicles that play a pivotal role in intercellular communication. Among various biological fluids, mammalian milk has emerged as an ideal source due to its safety, wide availability, and cost-effectiveness. Despite significant growth in this field, current evidence remains fragmented due to heterogeneity in biological sources, isolation protocols, purity standards, and stability assessment criteria. This critical review addresses this research gap by providing a systematic comparison of various milk sources and isolation methods with evaluating purity, yield, proteomic profiles, stability, and translational applicability and thereby elucidating the biomedical potential of these nanovesicles. Methods. In this critical review, relevant data were gathered by searching key terms (milk-derived exosomes, sources, extraction approaches, proteomics, stability, and biopharmaceutical applications) across the Web of Science, PubMed, Medline, and Scopus databases, covering literature from inception up to July 2026. All source materials associated with empirical studies were included in the analysis, whereas publications lacking accessible full texts were excluded. Results. The reviewed studies indicate that milk‑derived exosomes are capable of crossing biological barriers, entering target cells, and delivering molecular cargos including proteins, mRNA, miRNA, and lipids, thereby modulating recipient cell functions. Contaminants were shown to significantly affect exosome purity, highlighting the need for reproducible isolation techniques such as differential centrifugation, density‑gradient ultracentrifugation, size‑exclusion chromatography, and ExoQuick precipitation. LC‑MS/MS‑based proteomic analyses have enabled precise characterization of exosomal components and deeper insight into their biogenesis and functional roles. Evidence also demonstrates that milk‑derived exosomes exhibit considerable stability under various temperature conditions and in simulated gastrointestinal environments, effectively protecting their cargos. Moreover, preclinical studies emphasize their bioactive properties, therapeutic delivery potential, and utility as non‑invasive biomarkers for disease diagnosis. Conclusion. Milk‑derived exosomes represent a promising platform for biomedical applications and advanced drug delivery systems owing to their biological stability, efficient molecular cargo transport capacity, and high biocompatibility. Nevertheless, standardization of isolation procedures and further clinical evaluations are essential to fully realize their therapeutic potential. Practical Implications. Milk‑derived exosomes can serve as safe and naturally biocompatible nanocarriers for drug and gene delivery. Their stability and ability to cross biological barriers make them promising candidates for the development of novel therapeutic systems, functional foods, and non‑invasive diagnostic biomarkers.

Keywords: Milk-derived exosomes, Sources, Isolation approaches, Proteomics, Stability, Biopharmaceutical applications