Cyclodextrin single isomer-based vesicle for chlorin e6 delivery and enhanced efficiency of photodynamic therapy for cancer treatment

•An amphiphilic and cationic single-isomer cyclodextrin (CD-IL) was designed.•The vesicular assemblies of CD-IL and commercial photosensitizer Ce6 was prepared.•The performance of Ce6 in assemblies could be improved.•The greatly improved PDT efficiency of CD-CE was fully verified. In the field of cancer therapy, photodynamic therapy (PDT) is an emerging treatment modality that utilized light, photosensitizers (PSs), and oxygen to generate reactive oxygen species (ROS) to destroy tumor sites selectively. Conventional PSs experience issues such as poor water solubility and low bioavailability. The widely developed PS delivery nanosystems can address these problems, but most of them usually depend on relatively complex components and time-consuming synthesis procedures. Therefore, PS delivery vehicles with more easily obtained components and simpler preparation methods need to be explored. In this study, amphiphilic and cationic single-isomer cyclodextrin (CD-IL) was designed, which could co-assemble with chlorin e6 (Ce6, a commercially available PS) via multiple non-covalent interactions. The obtained nanovesicles (CD-CE) could not only overcome the inherent drawbacks of free Ce6, but also exhibit improved PDT efficacy in a series of cell-related experiments, including favorable stability, preferable cellular uptake, and enhanced phototoxicity. Thus, CD-CE prepared by the co-assembly of simple building blocks could be a facile option for PDT clinical applications.