Research progress on traditional Chinese medicine nanoemulsion

Introduction Traditional Chinese medicine (TCM) nanoemulsion is regarded as an innovative application of nanotechnology in herbal formulations, which can enhance drug solubility, stability, and bioavailability by encapsulating active herbal components in nanoscale droplets. Methods A systematic literature search was performed in the following electronic databases: PubMed, ScienceDirect , Wiley , Springer , China National Knowledge Infrastructure, and Wanfang databases. The information retrieval covered the period from January 2016 to June 2026, and the keywords and their combinations were selected, including “nanoemulsion” “traditional Chinese medicine” “Chinese herbal medicine” “preparation method” “high-pressure homogenization” “ultrasonic emulsification” “phase inversion temperature” “self-emulsification” “formulation optimization” and “process parameters”. The search was limited to original research articles and systematic reviews published in the English or Chinese journals, which excluded the conference abstracts, case reports, patents, and publications. Reference lists of all included articles and relevant reviews were manually screened to identify additional eligible studies. The initial search yielded 487 records, and the full texts of potentially eligible articles were then retrieved and assessed; finally, 92 eligible references were included for systematic analysis. Results this paper systematically reviews the definition, classification, formation mechanisms, and the advantages of traditional Chinese TCM nanoemulsion, and also comprehensively summarizes the application of high-energy emulsification and low-energy emulsification methods. Furthermore, it analyzes the key factors affecting the preparation process, including components of the aqueous phase, oil phase, and emulsifiers. Discussion this review provides an important reference for formula optimization, process improvement and quality control of TCM nanoemulsion, and offers a critical support for accelerating the standardization and internationalization of TCM preparations.