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Nanomotors have been extensively explored for various applications in nanomedicine, especially in cargo transportation. Motile properties enable them to deliver pharmaceutical ingredients more efficiently to the targeted site. However, it still remains a challenge to design motor systems that are therapeutically active and can also be effectively traced when taken up by cells. Here, we designed a nanomotor with integrated fluorescence and therapeutic potential based on biodegradable polymersomes equipped with aggregation-induced emission (AIE) agents. The AIE segments provided the polymersomes with autofluorescence, facilitating the visualization of cell uptake. Furthermore, the membrane structure enabled the reshaping of the AIE polymersomes into asymmetric, peanut-shaped polymersomes. Upon laser irradiation, these peanut polymersomes not only displayed fluorescence, but also produced reactive oxygen species (ROS). Because of their specific shape, the ROS gradient induced motility in these particles. As ROS is also used for cancer cell treatment, the peanut polymersomes not only acted as delivery vehicles but also as therapeutic agents. As an integrated platform, these peanut polymersomes therefore represent an interesting delivery system with biomedical potential.

Bowl-shaped biodegradable polymersomes, or stomatocytes, have much potential as drug delivery systems, due to their intriguing properties, such as controllable size, programmable morphology, and versatile cargo encapsulation capability. In this contribution, we developed well-defined therapeutically active stomatocytes with aggregation-induced emission (AIE) features by self-assembly of biodegradable amphiphilic block copolymers, comprising poly(ethylene glycol) (PEG) and AIEgenic poly(trimethylene carbonate) (PTMC) moieties. The presence of the AIEgens endowed the as-prepared stomatocytes with intrinsic fluorescence, which was employed for imaging of cellular uptake of the particles. It simultaneously enabled the photo-mediated generation of reactive oxygen species (ROS) for photodynamic therapy. The potential of the therapeutic stomatocytes as cargo carriers was demonstrated by loading enzymes (catalase and glucose oxidase) in the nanocavity, followed by a cross-linking reaction to achieve stable encapsulation. This provided the particles with a robust motile function, which further strengthened their therapeutic effect. With these unique features, enzyme-loaded AIEgenic stomatocytes are an attractive platform to be exploited in the field of nanomedicine.