Fatty acid vesicles as nanodrug delivery carriers: research progress and perspective

Fatty acid vesicles (FAVs) are closed lipid bilayer nanostructures self-assembled from fatty acids and their ionised derivatives, featuring facile preparation, low cost and excellent biocompatibility, which endows them promising prospects in drug delivery. This study systematically compares FAVs with conventional phospholipid liposomes, highlighting the core limitations of FAVs including high pH sensitivity and poor structural stability in physiological environments. Common stabilisation strategies are summarised, mainly covering chemical modification and amphiphilic additive incorporation. Classic fabrication approaches such as thin-film hydration, alcohol-assisted vesiculation and spontaneous self-assembly from fatty-acid precursors are introduced, together with emerging industrial techniques represented by microfluidics and dynamic high-pressure microjets. The applications of FAVs in transdermal, oral and anticancer drug delivery are also reviewed. FAVs exhibit distinct advantages in improving the bioavailability of insoluble drugs, enhancing transdermal permeability and achieving targeted delivery. Nevertheless, physiological pH instability, inadequate in vivo pharmacokinetic and safety data, and underdeveloped industrial preparation technologies still hinder their clinical transformation. Future research should prioritise developing pH-stable FAVs and evaluating their in vivo performance to promote their clinical translation.