Supramolecular Design of Unsymmetric Reverse Bolaamphiphiles for Cell‐Sensitive Hydrogel Degradation and Drug Release

Therapeutic Supramolecular Polymers: Designs and Applications

The self-assembly of low-molecular-weight building motifs into supramolecular polymers has unlocked a new realm of materials with distinct properties and tremendous potential for advancing medical practices. Leveraging the reversible and dynamic nature of non-covalent interactions, these supramolecular polymers exhibit inherent responsiveness to their microenvironment, physiological cues, and biomolecular signals, making them uniquely suited for diverse biomedical applications. In this review, we intend to explore the principles of design, synthesis methodologies, and strategic developments that underlie the creation of supramolecular polymers as carriers for therapeutics, contributing to the treatment and prevention of a spectrum of human diseases. We delve into the principles underlying monomer design, emphasizing the pivotal role of non-covalent interactions, directionality, and reversibility. Moreover, we explore the intricate balance between thermodynamics and kinetics in supramolecular polymerization, illuminating strategies for achieving controlled sizes and distributions. Categorically, we examine their exciting biomedical applications: individual polymers as discrete carriers for therapeutics, delving into their interactions with cells, and in vivo dynamics; and supramolecular polymeric hydrogels as injectable depots, with a focus on their roles in cancer immunotherapy, sustained drug release, and regenerative medicine. As the field continues to burgeon, harnessing the unique attributes of therapeutic supramolecular polymers holds the promise of transformative impacts across the biomedical landscape.

Diffusion-Limited Processes in Hydrogels with Chosen Applications from Drug Delivery to Electronic Components

Diffusion is one of the key nature processes which plays an important role in respiration, digestion, and nutrient transport in cells. In this regard, the present article aims to review various diffusion approaches used to fabricate different functional materials based on hydrogels, unique examples of materials that control diffusion. They have found applications in fields such as drug encapsulation and delivery, nutrient delivery in agriculture, developing materials for regenerative medicine, and creating stimuli-responsive materials in soft robotics and microrobotics. In addition, mechanisms of release and drug diffusion kinetics as key tools for material design are discussed.

Modular Peptide Probe for Protein Analysis

The analysis and regulation of proteins are of great significance for the development of disease diagnosis and treatment. However, complicated analytical environment and complex protein structure severely limit the accuracy of their analysis results. Nowadays, ascribing to the editability and bioactivity of peptides, peptide-based probes could meet the requirements of good selectivity and high affinity to overcome the challenges. In this review, we summarize the advances in the use of modular peptide probes for proteins analysis. It focuses on how to design and optimize the structure of probes, as well as their performance. Then, the strategies and application to improve the analysis result of modular peptide probes are introduced. Finally, we also discuss current challenge and provide some ideas for the future direction for modular peptide probes, hoping to accelerate their clinical transformation.

Tumor microenvironment-activated multi-functional nanodrug with size-enlargement for enhanced cancer phototheranostics

Phototheranostics that integrate diagnosis and treatment modalities have shown great promise in personalized cancer therapy. However, the "always on" characteristics often lead to suboptimal imaging quality and severe side effects. Herein, we report the construction of a perylenemonoimide based nanodrug CPMI NP with multi-functional activatable theranostic capability. The nanodrug is facilely co-assembled from a prodrug CPMI and DSPE-mPEG2000. In a tumor microenvironment (TME) with excessive glutathione (GSH), CPMI undergoes a cascade reaction to generate the phototheranostic molecule NPMI and the chemodrug chlorambucil, simultaneously switching on the near-infrared (NIR) fluorescence, photothermal effect, and drug release. The photothermal conversion efficiency is as high as 52.2%. Moreover, NPMI exhibits an enhanced intermolecular π-π stacking effect, leading to significant size-enlargement of the nanodrug and prolonged tumor retention. Due to TME-activation, the strong in vivo fluorescence signal of the tumor can be observed 144 h post injection with a high signal-to-noise ratio of up to 17. The enhanced tumor inhibition efficiency of the nanodrug is confirmed through activatable chemo-photothermal therapy. This work paves the way for the design of activatable phototheranostic agents for accurate cancer diagnosis and treatment.

Responsive Peptide Nanofibers with Theranostic and Prognostic Capacity

Photodynamic therapy (PDT) is a highly promising therapeutic modality for cancer treatment. The development of stimuli-responsive photosensitizer nanomaterials overcomes certain limitations in clinical PDT. Herein, we report the rational design of a highly sensitive PEGylated photosensitizer-peptide nanofiber (termed PHHPEG6 NF) that selectively aggregates in the acidic tumor and lysosomal microenvironment. These nanofibers exhibit acid-induced enhanced singlet oxygen generation, cellular uptake, and PDT efficacy in vitro, as well as fast tumor accumulation, long-term tumor imaging capacity and effective PDT in vivo. Moreover, based on the prolonged presence of the fluorescent signal at the tumor site, we demonstrate that PHHPEG6 NFs can also be applied for prognostic monitoring of the efficacy of PDT in vivo, which would potentially guide cancer treatment. Therefore, these multifunctional PHHPEG6 NFs allow control over the entire PDT process, from visualization of photosensitizer accumulation, via actual PDT to the assessment of the efficacy of the treatment.

Glucose-Fueled Peptide Assembly: Glucagon Delivery via Enzymatic Actuation

Nature achieves remarkable function from the formation of transient, nonequilibrium materials realized through continuous energy input. The role of enzymes in catalyzing chemical transformations to drive such processes, often as part of stimuli-directed signaling, governs both material formation and lifetime. Inspired by the intricate nonequilibrium nanostructures of the living world, this work seeks to create transient materials in the presence of a consumable glucose stimulus under enzymatic control of glucose oxidase. Compared to traditional glucose-responsive materials, which typically engineer degradation to release insulin under high-glucose conditions, the transient nanofibrillar hydrogel materials here are stabilized in the presence of glucose but destabilized under conditions of limited glucose to release encapsulated glucagon. In the context of blood glucose control, glucagon offers a key antagonist to insulin in responding to hypoglycemia by signaling the release of glucose stored in tissues so as to restore normal blood glucose levels. Accordingly, these materials are evaluated in a prophylactic capacity in diabetic mice to release glucagon in response to a sudden drop in blood glucose brought on by an insulin overdose. Delivery of glucagon using glucose-fueled nanofibrillar hydrogels succeeds in limiting the onset and severity of hypoglycemia in mice. This general strategy points to a new paradigm in glucose-responsive materials, leveraging glucose as a stabilizing cue for responsive glucagon delivery in combating hypoglycemia. Moreover, compared to most fundamental reports achieving nonequilibrium and/or fueled classes of materials, the present work offers a rare functional example using a disease-relevant fuel to drive deployment of a therapeutic.

Structure-Based Programming of Supramolecular Assemblies in Living Cells for Selective Cancer Cell Inhibition

Here we report on the design, synthesis, and assembly of an enzymatic programmable peptide system inspired by endocytic processes to induce molecular assemblies formation spatiotemporally in living cancer cells, resulting in glioblastoma cell death mainly in necroptosis. Our results indicate the stability and glycosylation of molecules play an essential role in determining the final bioactivity. Detailed mechanistic studies by CLSM, Flow cytometry, western blot, and Bio-EM suggest the site-specific formation of assemblies, which could induce the LMP and activate the downstream cell death pathway. Moreover, we also demonstrate that our strategy can boost the activity of commercial chemotherapy drug by escaping lysosome sequestration. We expected this work would be expanded towards artificial intelligent biomaterials for cancer therapy and imaging precisely.

Cell Death Mediated by the Pyroptosis Pathway with the Aid of Nanotechnology: Prospects for Cancer Therapy

Pyroptosis, a unique form of programmed cell death (PCD) that is characterized by DNA fragmentation, chromatin condensation, cellular swelling with big bubbles, and leakage of cell content, has been proven to have a close relationship with human diseases, such as inflammatory diseases and malignant tumors. Since a new gasdermin-D (GSDMD) protein was identified in 2015, various strategies have been developed to induce pyroptosis for cancer therapy, including ions, small-molecule drugs and nanomaterials. Although there are a number of reviews about the close relationship between the pyroptosis mechanism and the occurrence of various cancers, a summary covering recent progress in the field of nanomedicines in pyroptosis-based cancer therapy has not yet been presented. Therefore, it is urgent to fill this gap and light up future directions for the use of this powerful tool to combat cancer. In this Minireview, recent progress in cancer treatment based on pyroptosis induced by nanoparticles will be described in detail, the design highlights and the therapeutic advantages are emphasized, and future perspectives in this emerging area are proposed.