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The development of phototheranostic agents, specifically those based on organic small molecules (OSMs) with long wavelength excitation/emission, is an attractive but challenging project. In this contribution, we designed and synthesized a novel conjugate small molecule with a linear structure, named DPP-OPIC. Water-soluble nanoparticle DPP-OPIC NPs were fabricated. They exhibited strong absorption in the region of 600–1000 nm, which was due to the extended conjugate length of the molecular skeleton and J-aggregation behavior. Under 808 nm laser excitation, DPP-OPIC NPs were capable of producing outstanding near-infrared-II (NIR-II, 900–1700 nm) fluorescence. The photoluminescence quantum yield was determined as 0.58%, which enabled high-resolution in vivotumor imaging. Additionally, a notable photothermal effect with a high photothermal conversion efficiency (41.5%) was achieved by the irradiation of DPP-OPIC NPs. Hence, DPP-OPIC NPs can be used as superior phototheranostic agents, providing valuable contributions to NIR-II fluorescence imaging and photothermal therapy.

[Display omitted] While polyrotaxanes have found applications in the construction of diverse soft materials, there is a limited exploration on mechanical force-responsive phosphorescence emission systems. Recently, Yong Chen, Yu Liu, and co-workers from Nankai University have addressed this gap by developing a novel type of supramolecular elastomer exhibiting reversible phosphorescent behavior. This innovative material displays stretch-induced phosphorescence enhancement and has been successfully employed for information storage and encryption in specialized environments.

The construction of supramolecular polymer networks (SPNs) with high robustness remains a significant challenge in materials science. Achieving this goal typically requires a substantial usage of supramolecular linkers, which can limit their practical applications. Recently, Shijun Li, Peter Stang, Feihe Huang, Jianying Huang and co-workers have pioneered a method to address this limitation. They have successfully developed robust SPNs utilizing only a minute quantity of metallacycles (0.28 mol%) as supramolecular crosslinkers. This innovative approach not only enhances the mechanical properties of the SPNs but also enables excellent stimuli-responsiveness, thereby broadening their potential applications. [Display omitted]

Stepwise energy transfer is ubiquitous in natural photosynthesis, which greatly promotes the widespread use of solar energy. Herein, we constructed a supramolecular light harvesting system based on sequential energy transfer through the hierarchical self-assembly of M, which contains a cyanostilbene core flanked by two ureidopyrimidinone motifs, endowing itself with both aggregation-induced emission behavior and quadruple hydrogen bonding ability. The monomer Mcan self-assemble into hydrogen bonded polymers and then form supramolecular polymeric nanoparticles in water through a mini-emulsion process. The nanoparticles were further utilized to encapsulate the relay acceptor ESY and the final acceptor NDI to form a two-step FRET system. Tunable fluorescence including a white-light emission was successfully achieved. Our work not only shows a desirable way for the fabrication of efficient two-step light harvesting systems, but also shows great potential in tunable photoluminescent nanomaterials.

A fixed-tetraphenylethylene (FTPE) motif bridged ditopic benzo-21-crown-7 molecule was prepared. In the presence of a ditopic dialkylammonium salt guest molecule, a fluorescent supramolecular polymer with golden emission was developed.

Recent developments on supramolecular polymers fabricated by orthogonal self-assembly based on hydrogen bonding and host–guest interactions were summarized.

Sequential energy transfer is ubiquitous in natural light-harvesting systems (LHSs), which greatly promotes the exploitation of light energy. The LHSs in nature are sophisticated supramolecular assemblies of chlorophyll molecules that carry out efficient light harvesting through cascade energy transfer process. Inspired by nature, scientists have paid much attention to fabricate stepwise LHSs based on assorted supramolecular scaffolds in recent years. Light-harvesting antennas and energy acceptors can be accommodated in particular scaffolds, which offer great convenience for energy transfer between them. These systems not only further mimic photosynthesis, but also demonstrate many potential applications, such as photocatalysis, tunable luminescence, and information encryption, etc. In this review article, aiming at offering a practical guide to this emerging research field, the introduction of construction strategies towards sequential LHSs will be presented. Different scaffolds are classified and highlighted, including host-guest assemblies, metal-coordination assemblies, as well as bio-macromolecular and other supramolecular scaffolds.

Recent progress on artificial light-harvesting systems fabricated by supramolecular host–guest interaction was summarized.

The construction of nanotubes with precise parametric structures is a challenge that has stimulated an ever increasing amount of research interest. Recently, Andrew C.-H. Sue and co-workers from Xiamen University have reported a type of discrete chiral nanotube derived from rim-desymmetrized macrocycles. These macrocycles exhibit strong inclusion affinities for linear alkane derivatives with complementary parameters. [Display omitted]

Fluorescent materials that respond to multiple stimuli have broad applications ranging from sensing and bioimaging to information encryption. Herein, we report the design and synthesis of a single-fluorophore-based amphiphile DCSO, which shows temperature-, solvent-, humidity-, and radiation-dependent fluorescence. DCSOconsists of a dicyanostilbene (DCS) group as a rigid hydrophobic core with oligo(ethylene glycol) (OEG) chains at both ends as a flexible hydrophilic periphery. The DCS group acts as a highly efficient fluorophore, while the OEG chain endows the molecule with thermo-responsiveness. Fluorescent colors can vary from blue to green to yellow in response to external stimuli. On the basis of light radiation, we demonstrate that this system can be applied to time-dependent information encryption, in which the correct information can only be read at a specific time under irradiation. This work further demonstrates the usefulness and application of single-fluorophore-based luminescent materials with multiple stimuli-responsive functions.

By taking inspiration from green photosynthetic bacteria, Feng Wang and co-workers from University of Science and Technology of China have successfully constructed a sequential energy transfer system with high overall energy transfer efficiency through supramolecular copolymerization of three different σ-platinated (hetero)acenes. The reported fabrication strategy has the potential to greatly benefit future development of man-made photosynthesis systems.

A novel, bifunctional, quadruple hydrogen‐bonding ureido‐pyrimidinone (UPy) unit bridged by photochromic dithienylethene (1) has been synthesized, which affords linear assemblies in solution and undergoes concentration‐dependent ring‐opening polymerization. The two UPy functional groups of 1can dimerize intramolecularly to form a cyclic monomer with the two thienyl rings fixed in a parallel conformation, which prohibits its photocyclization. We exploited the photochemical reactivity and resonance difference of the linker of the bis‐UPy derivative as well as using the more typical 1H NMR, DOSY, and Ubbelohde viscometry methods to investigate for the first time the ring–chain polymerization mechanism. Moreover, we fabricated a mixed polymer film with a fluorescent dye noncovalently endcapping the linear photochromic assemblies through quadruple hydrogen bonds, which showed nondestructive fluorescent read‐out ability for data storage by fluorescence resonance energy transfer (FRET) from the fluorescent dye to the closed form of the diarylethene.