Although platinum-based anticancer drugs prevail in cancer treatment, their clinical applications are limited by the severe side effects as well as their ineffectiveness against drug resistant cancers. A precise combination of photodynamic therapy (PDT) and chemotherapy can synergistically improve the therapeutic outcome and thereby may overcome drug resistance through a multipronged assault. Herein, we employ the well-defined cavity of a discrete organoplatinum(II) metallacage (M) to encapsulate octaethylporphine (OEP), a photosensitizer, forming a dual-functionalized system M⊃OEP that is wrapped into the hydrophobic core of the nanoparticles (MNPs) self-assembled from an amphiphilic diblock copolymer. Using a copper-free click reaction, a targeting ligand is conjugated on the surface of the MNPs, aiming to specifically deliver a chemotherapeutic drug and a photosensitizer to cancer cells. Benefiting from the enhanced permeability and retention effect and active targeting capability, high tumor accumulation of MNPs is achieved, leading to an improved therapeutic outcome and reduced side effects. In vivo studies demonstrate that the combination of chemotherapy and PDT exhibits a superior antitumor performance against a drug-resistant tumor model attributed to their synergistic anticancer efficacy. supramolecular coordination complex | metallacage | photodynamic therapy | theranostic | drug delivery P latinum-based drugs including cisplatin, carboplatin, and oxaliplatin are used worldwide in cancer treatment; however, their dose-limiting side effects arising from the poor selectivity to cancerous tissue over normal tissues always cause serious complications in patients (1-5). Considerable attention has been given to the development of smart drug-delivery systems that can temporarily passivate platinum complexes and specifically transport the nanomedicines to tumor sites via the enhanced permeability and retention (EPR) effect (6-8). Various nanocarriers including liposomes, micelles, and dendrimers have been employed that can selectively transport platinum-based anticancer drugs to cancerous cells (9-11), while the clinical use of these nanomedicines is still limited by drug resistance, including inherent and acquired resistance, promoting researchers to combine chemotherapy with other treatment modalities to achieve synergetic anticancer efficacy through a multipronged assault (12-15).Photodynamic therapy (PDT) employs photosensitizers that upon absorbing a specific wavelength of light to release a cell-damaging version of reactive oxygen species (singlet oxygen, 1 O 2 ) that can eradicate tumors with a high specificity and negligible side effects (16)(17)(18). The sensitization effect of PDT can significantly boost the activity of chemotherapeutic agents, synergistically overcoming drug resistance through different mechanisms of actions to realize enhanced anticancer efficacy (19)(20)(21)(22). However, the full promise of PDT has not yet been achieved mainly due to the lack of ideal photosensitizers and sophisti...

Control of self-assembly is significant to the preparation of supramolecular materials and illustration of diversities in either natural or artificial systems. Supra-amphiphiles have remarkable advantages in the construction of nanostructures but control of shape and size of supramolecular nanostructures is still a great challenge. Here, we fabricate a series of supra-amphiphiles by utilizing the recognition motifs based on a heteroditopic porphyrin amphiphile and its zinc complex. These porphyrin amphiphiles can bind with a few guests including Cl – , coronene, C 60 , 4,4′-bipyridine and 2,4,6-tri(pyridin-4-yl)-1,3,5-triazine, which are further applied to facilitate the controllable self-assembly. Addition of these guests result in the formation of various supra-amphiphiles with well-defined structures, thus induce the generation of different aggregates. A diverse of aggregation morphologies including nanospheres, nanorods, films, spheric micelles, vesicles and macrowires are constructed upon the influence of specific complexation, which highlights the present work with abundant control on the shapes and dimensions of self-assemblies.

The template-directed strategy is a powerful method to construct porphyrin nanorings with high complexities, wherein metalloporphyrin precursors pre-organize via supramolecular interactions of the porphyrin or its central metal with a carefully selected template, and then react with each other to deliver a final cyclic multiporphyrin structure. In this article, we review the recent breakthroughs in the template-directed synthesis methods and new structures of porphyrin or metalloporphyrin nanorings, as well as their applications in host-guest chemistry and artificial light-harvesting.

Review: [44 refs.