Droplet Squeeze Microfluidic Platform for Generating Extracellular Vesicle Hybrids for Drug Delivery.

Extracellular vesicles (EVs) are emerging as versatile drug delivery systems due to their intrinsic biocompatibility and targeting capabilities. However, EV integrity and efficient drug loading challenges hinder their clinical translation. To address these limitations, hybrid systems integrating lipid nanoparticles (LNPs) with EVs have gained attention for their potential in targeted and combinatorial drug delivery. This study presents a robust microfluidic approach for the scalable generation of drug-loaded EV-LNP hybrids (EV hybrids). The method facilitates controlled fusion between EVs and LNPs by utilizing a droplet-mediated squeezing mechanism. Lipid composition and microfluidic parameters are optimized for the fusion of EVs and LNPs and determined physicochemical and functional characterizations of the EV hybrids. In vitro studies demonstrate that EV hybrids exhibit enhanced targeting efficiency. Moreover, small-molecule therapeutics are successfully encapsulated within EV hybrids, significantly improving cytotoxic efficacy against melanoma in 2D and 3D culture models compared to drug-loaded EVs or LNPs alone. The work introduces a scalable, minimally disruptive microfluidic platform for engineering EV hybrids, offering a promising strategy to advance precision nanomedicine.