Self-Assembled Peptide- and Protein-Based Nanomaterials for Antitumor Photodynamic and Photothermal Therapy

Self-Amplifying Assembly of Peptides in Macrophages for Enhanced Inflammatory Treatment

Enzyme-regulated in situ self-assembly of peptides represents one versatile strategy in the creation of theranostic agents, which, however, is limited by the strong dependence on enzyme overexpression. Herein, we reported the self-amplifying assembly of peptides precisely in macrophages associated with enzyme expression for improving the anti-inflammatory efficacy of conventional drugs. The self-amplifying assembling system was created via coassembling an enzyme-responsive peptide with its derivative functionalized with a protein ligand. Reduction of the peptides by the enzyme NAD(P)H quinone dehydrogenase 1 (NQO1) led to the formation of nanofibers with high affinity to the protein, thereby facilitating NQO1 expression. The improved NQO1 level conversely promoted the assembly of the peptides into nanofibers, thus establishing an amplifying relationship between the peptide assembly and the NQO1 expression in macrophages. Utilization of the amplifying assembling system as vehicles for drug dexamethasone allowed for its passive targeting delivery to acute injured lungs. Both in vitro and in vivo studies confirmed the capability of the self-amplifying assembling system to enhance the anti-inflammatory efficacy of dexamethasone via simultaneous alleviation of the reactive oxygen species side effect and downregulation of proinflammatory cytokines. Our findings demonstrate the manipulation of the assembly of peptides in living cells with a regular enzyme level via a self-amplification process, thus providing a unique strategy for the creation of supramolecular theranostic agents in living cells.

Extracellular vesicles with high dual drug loading for safe and efficient combination chemo-phototherapy

Extracellular vesicles (EVs) have emerged as biocompatible nanocarriers for efficient delivery of various therapeutic agents, with intrinsic long-term blood circulatory capability and low immunogenicity. Here, indocyanine green (ICG)- and paclitaxel (PTX)-loaded EVs [EV(ICG/PTX)] were developed as a biocompatible nanoplatform for safe and efficient cancer treatment through near-infrared (NIR) light-triggered combination chemo/photothermal/photodynamic therapy. High dual drug encapsulation in EVs was achieved for both the hydrophilic ICG and hydrophobic PTX by simple incubation. The EVs substantially improved the photostability and cellular internalization of ICG, thereby augmenting the photothermal effects and reactive oxygen species production in breast cancer cells upon NIR light irradiation. Hence, ICG-loaded EVs activated by NIR light irradiation showed greater cytotoxic effects than free ICG. EV(ICG/PTX) showed the highest anticancer activity owing to the simultaneous chemo/photothermal/photodynamic therapy when compared with EV(ICG) and free ICG. In vivo study revealed that EV(ICG/PTX) had higher accumulation in tumors and improved pharmacokinetics compared to free ICG and PTX. In addition, a single intravenous administration of EV(ICG/PTX) exhibited a considerable inhibition of tumor proliferation with negligible systemic toxicity. Thus, this study demonstrates the potential of EV(ICG/PTX) for clinical translation of combination chemo-phototherapy.

Amantadine-assembled nanostimulator enhances dimeric RBD antigen-elicited cross-neutralization against SARS-CoV-2 strains

There is an urgent need to develop new vaccination strategies to elevate the cross-neutralization against different SARS-CoV-2 strains. In this study, we construct the spherical amantadine-assembled nanostimulator (AAS). Amantadine as immunostimulating molecules are displayed on the outermost layer of AAS. Molecular mechanism analysis reveals that AAS can activate RIG-I-like receptor (RLR) signaling pathway to increase the expression of type I interferons in vivo. AAS-mediated activation of RLR signaling pathway further promotes the maturation and proliferation of dendritic cells (DCs) and T helper cells (Ths), finally activating B cells to produce potent antibody responses. In performance evaluation experiments, the mixture of AAS and dimeric RBD significantly enhances RBD-specific humoral responses (4-fold IgG, 3.5-fold IgG2a, 3.3-fold IgG2b, 3.8-fold IgG3 and 1.3-fold IgM), in comparison to aluminum adjuvant-assistant dimeric RBD. Importantly, AAS dramatically elevates dimeric RBD-elicited cross-neutralization against different SARS-CoV-2 strains such as Wuhan-Hu-1 (9-fold), B.1.1.7 (UK variant, 15-fold), B.1.351 (South African variant, 4-fold) and B.1.617.2 (India variant, 7-fold). Our study verifies the mechanism of AAS in activating RLR signaling pathway in host immune system and highlights the power of AAS in improving antigen-elicited cross-neutralization against different SARS-CoV-2 strains.

Functional Nanomaterials Based on Self-Assembly of Endogenic NIR-Absorbing Pigments for Diagnostic and Therapeutic Applications

Endogenic pigments derived from hemoglobin have been successfully applied in the clinic for both imaging and therapy based on their inherent photophysical and photochemical properties, including light absorption, fluorescence emission, and producing reactive oxygen species. However, the clinically approved endogenic pigments can be excited only by UV/vis light, restricting the penetration depth of in vivo applications. Recently, endogenic pigments with NIR-absorbing properties have been explored for constructing functional nanomaterials. Here, the overview of NIR-absorbing endogenic pigments, mainly bile pigments, and melanins, as emerging building blocks for supramolecular construction of diagnostic and therapeutic nanomaterials is provided. The endogenic origins, synthetic pathways, and structural characteristics of the NIR-absorbing endogenic pigments are described. The self-assembling approaches and noncovalent interactions in fabricating the nanomaterials are emphasized. Since bile pigments and melanins are inherently photothermal agents, the resulting nanomaterials are demonstrated as promising candidates for photoacoustic imaging and photothermal therapy. Integration of additional diagnostic and therapeutic agents by the nanomaterials through chemical conjugation or physical encapsulation toward synergetic effects is also included. Especially, the degradation behaviors of the nanomaterials in biological environments are summarized. Along with the challenges, future perspectives are discussed for accelerating the ration design and clinical translation of NIR-absorbing nanomaterials.

Multifunctional Self-Assembly with NIR Light-Activated Cascade Effect for Improving Local Treatment on Solid Tumors

Incomplete local treatment of solid tumors is the main cause of tumor difficult to cure, and easily leads to tumor metastasis and recurrence. The dense external matrix and hypoxic microenvironment of solid tumors severely restrict the therapy efficacy of local tumors. Enhancing the infiltration ability of agents to tumor tissues and adapting the therapy mode favored to hypoxic microenvironments are beneficial to improve the cure rate of tumors. In this work, we designed and developed a self-assembled biomaterial with a cascade effect triggered by near-infrared light. The self-assembly was combined of biotin, phase change material (PNIPAM), photochemical agent (ATT-2), and alkyl radical generator (AIPH). In the assembly, biotin acted as a targeted group. ATT-2 was used to provide heat to synergistically induce the phase change and decompose alkyl radicals. The superficial and deep tumors were ablated by heat and alkyl radicals with white light irradiation of the assembly, respectively. The assay in vivo showed that the self-assembly could effectively eliminate local lesions of solid tumors. This work provides new insights for improving the cure rate of tumors, which not only develops biomaterials adapted to the tumor microenvironment, but also proposes new therapies for complete elimination of solid tumors.

A Photosensitizer Discretely Loaded Nanoaggregate with Robust Photodynamic Effect for Local Treatment Triggers Systemic Antitumor Responses

Photodynamic therapy (PDT), is a rising star for suppression of in situ and metastatic tumors, yet it is impeded by low ROS production and off-target phototoxicity. Herein, an aggregation degree editing strategy, inspired by gene editing, was accomplished by the coordination of an aggregation degree editor, p(MEO₂MA₁₆₀-co-OEGMA₄₀)-b-pSS₃₀ [POEGS; MEO₂MA = 2-(2-methoxyethoxy)ethyl methacrylate, OEGMA = oligo(ethylene glycol) methacrylate; pSS = poly(styrene sulfonate)] and indocyanine green (ICG) to nontoxic Mg²⁺, forming an ICG discretely loaded nanoaggregate (ICG-DNA). Optimization of the ICG aggregation degree [POEGS/ICG (P/I) = 6.55] was achieved by tuning the P/I ratio, alleviating aggregation-caused-quenching (ACQ) and photobleaching concurrently. The process boosts the PDT efficacy, spurring robust immunogenic cell death (ICD) and systemic antitumor immunity against primary and metastatic immunogenic "cold" 4T1 tumors via intratumoral administration. Moreover, the temperature-sensitive phase-transition property facilitates intratumoral long-term retention of ICG-DNA, reducing undesired phototoxicity to normal tissues; meanwhile, the photothermal-induced tumor oxygenation further leads to an augmented PDT outcome. Thus, this simple strategy improves PDT efficacy, boosting the singlet oxygen quantum yield (Φ_Δ)-dependent ICD effect and systemic antitumor responses via local treatment.

Numerical Study on Death of Squamous Cell Carcinoma Based on Various Shapes of Gold Nanoparticles Using Photothermal Therapy

Due to increased exposure to ultraviolet radiation caused by increased outdoor activities, the incidence of skin cancer is increasing. Incision is the most typical method for treating skin cancer, and various treatments that can minimize the risks of incision surgery are being investigated. Among them, photothermal therapy is garnering attention because it does not cause bleeding and affords rapid recovery. In photothermal therapy, tumor death is induced via temperature increase. In this study, a numerical study based on heat transfer theory was conducted to investigate the death of squamous cell carcinoma located in the skin layer based on various shapes of gold nanoparticles (AuNPs) used in photothermal therapy. The quantitative correlation between the conditions of various AuNPs and the laser intensity that yields the optimal photothermal treatment effect was derived using the effective apoptosis ratio. It was confirmed that optimal conditions exist for maximizing apoptosis within a tumor tissue and minimizing the thermal damage to surrounding normal tissues when using AuNPs under various conditions. Furthermore, it is envisioned that research result will be utilized as a standard for photothermal treatment in the future.

Supramolecular cancer photoimmunotherapy based on precise peptide self-assembly design

Combinational photoimmunotherapy (PIT) is considered to be an ideal strategy for the treatment of highly recurrent and metastatic cancer, because it can ablate the primary tumor and provide in situ an autologous tumor vaccine to induce the host immune response, ultimately achieving the goal of controlling tumor growth and distal metastasis. Significant efforts have been devoted to enhancing the immune response caused by phototherapy-eliminated tumors. Recently, supramolecular PIT nanoagents based on precise peptide self-assembly design have been employed to improve the efficacy of photoimmunotherapy by utilizing the stability, targeting capability and flexibility of drugs, increasing tumor immunogenicity and realizing the synergistic amplification of immune effects through multiple pathways and collaborative strategy. This review summarizes peptide-based supramolecular PIT nanoagents for phototherapy-synergized cancer immunotherapy and its progress in enhancing the effect of photoimmunotherapy, especially focusing on the design of peptide-based PIT nanoagents, the progress of bioactive peptides combined photoimmunotherapy, and the synergistic immune-response mechanism.

Self-assembled nanoparticles based on supramolecular-organic frameworks and temoporfin for an enhanced photodynamic therapy in vitro and in vivo

Water-soluble three-dimensional supramolecular-organic frameworks (SOFs) and temoporfin (mTHPC) are discovered to form uniform self-assembled nanoparticles. These nanoparticles demonstrate an improved ¹O₂ generation efficiency due to the reduced aggregation-caused quenching effect. SOFs and self-assembled nanoparticles are biocompatible. Self-assembled nanoparticles display an improved photo cytotoxicity toward four types of human cancer cells. The tumor model in mice shows that self-assembled nanoparticles could efficiently suppress tumor growth in vivo.

Glycol chitosan/iron oxide/polypyrrole nanoclusters for precise chemodynamic/photothermal synergistic therapy

Noninvasive photothermal therapy (PTT) represents a promising direction for more modern and precise medical applications. However, PTT efficacy is still not satisfactory due to the existence of heat shock proteins (HSPs) and poorly targeted delivery. Herein, the design of a nanosystem with improved delivery efficacy for anticancer treatment employing the synergetic effects of reactive oxygen species (ROS)-driven chemodynamic therapy (CDT) to inactivated HSPs with photothermal-hyperthermia was therefore achieved through the development of pH-targeting glycol chitosan/iron oxide enclosed core polypyrrole nanoclusters (GCPI NCs). The designed NCs effectively accumulated toward cancer cells due to their acidic microenvironment, initiating ROS generation via Fenton reaction at the outset and performing site-specific near infrared (NIR)-photothermal effect. A comprehensive analysis of both surface and bulk material properties of the CDT/PTT NCs as well as biointerface properties were ascertained via numerous surface specific analytical techniques by bringing together heightened accumulation of CDT/PTT NCs, which can significantly eradicate cancer cells thus minimizing the side effects of conventional chemotherapies. All of these attributes act in synergy over the cancer cells succeeding in fashioning NC's able to act as competent agents in the MRI-monitored enhanced CDT/PTT synergistic therapy. Findings in this study evoke attention in future oncological therapeutic strategies.

A GSH/CB Dual-Controlled Self-Assembled Nanomedicine for High-Efficacy Doxorubicin-Resistant Breast Cancer Therapy

Chemoresistance is a major therapeutic obstacle in the treatment of breast cancer. Therefore, how to overcome chemoresistance is a problem to be solved. Here, a glutathione (GSH)/cathepsin B (CB) dual-controlled nanomedicine formed by cyclic disulfide-bridged peptide (cyclic-1a) as a potent anticancer agent is reported. Under the sequential treatment of GSH and CB, cyclic-1a can efficiently self-assemble into nanofibers. In vitro studies show that cyclic-1a promotes the apoptosis of MCF-7/DOX cells by inducing the cleavages of caspase-3 and PARP. In vivo studies confirm that cyclic-1a significantly inhibits the progression of MCF-7/DOX cells-derived xenograft in nude mice, with no obvious adverse reactions. This study provides a paradigm of GSH/CB dual-controlled nanomedicine for high-efficacy and low-toxic DOX-resistant breast cancer therapy.

S-Benzyl Cysteine Based Cyclic Dipeptide Super Hydrogelator: Enhancing Efficacy of an Anticancer Drug via Sustainable Release

Peptide based low molecular weight supramolecular hydrogels hold promising aspects in various fields of application especially in biomaterial and biomedical sciences such as drug delivery, wound healing, tissue engineering, cell proliferation, etc due to their extreme biocompatibility. Unlike linear peptides, cyclic peptides have more structural rigidity and tolerance to enzymatic degradation and high environmental stability which make them even better candidates for the above said applications. Herein, a new small cyclic dipeptide (CDP) cyclo-(Leu-S-Bzl-Cys) (P1) consisting of L-leucine and S-benzyl protected L-cysteine was reported which formed hydrogel at physiological conditions (at 37^o C and pH=7.46). The hydrogel formed from the cyclic dipeptide P1 showed very good tolerance towards environmental parameters such as pH, temperature and was seen to be stable for more than a year without any deformation. The hydrogel was thermoreversible and stable in the pH range 6-12. Mechanical strength of P1 hydrogel was measured by rheology experiment. AFM and FE-SEM images revealed that in aqueous solvents P1 self-assembled into a highly cross-linked nanofibrillar network which immobilized water molecules inside the cages and formed the hydrogel. The self-assembled cyclic dipeptide acquired antiparallel β-sheet secondary structure which was evident from CD and FT-IR studies. The β-sheet arrangement and formation of amyloid fibrils were further established by ThT binding assay. Furthermore, P1 was able to form hydrogel in presence of anticancer drug 5-fluorouracil (5FU) and sustainable release of the drug from the hydrogel was measured in-vitro. The hydrogelator P1 showed almost no cytotoxicity towards human colorectal cancer cell line HCT116 up to a considerable high concentration and showed potential application in sustainable drug delivery. The co-assembly of 5FU and P1 hydrogel exhibited much better anticancer activity towards HCT116 cancer cell line than 5-fluorouracil alone and decreased the IC₅₀ dose of 5-fluorouracil to a much lower value.

Nanomedicine-enabled chemotherapy-based synergetic cancer treatments

Chemotherapy remains one of the most prevailing regimens hitherto in the fight against cancer, but its development has been being suffering from various fatal side effects associated with the non-specific toxicity of common chemical drugs. Advances in biomedical application of nanomedicine have been providing alternative but promising approaches for cancer therapy, by leveraging its excellent intrinsic physicochemical properties to address these critical concerns. In particular, nanomedicine-enabled chemotherapy has been established as a safer and promising therapeutic modality, especially the recently proposed nanocatalytic medicine featuring the capabilities to generate toxic substances by initiating diverse catalytic reactions within the tumor without directly relying on highly toxic but non-selective chemotherapeutic agents. Of special note, under exogenous/endogenous stimulations, nanomedicine can serve as a versatile platform that allows additional therapeutic modalities (photothermal therapy (PTT), photodynamic therapy (PDT), chemodynamic therapy (CDT), etc.) to be seamlessly integrated with chemotherapy for efficacious synergistic treatments of tumors. Here, we comprehensively review and summarize the representative studies of multimodal synergistic cancer treatments derived from nanomedicine and nanocatalytic medicine-enabled chemotherapy in recent years, and their underlying mechanisms are also presented in detail. A number of existing challenges and further perspectives for nanomedicine-synergized chemotherapy for malignant solid tumor treatments are also highlighted for understanding this booming research area as comprehensively as possible.

Tailoring Peptide Self-Assembly and Formation of 2D Nanoribbons on Mica and HOPG Surface

Studying the interactions between biomolecules and material interfaces play a crucial role in the designing and synthesizing of functional bionanomaterials with tailored structure and function. Previously, a lot of studies were performed on the self-assembly of peptides in solution through internal and external stimulations, which mediated the creation of peptide nanostructures from zero-dimension to three-dimension. In this study, we demonstrate the self-assembly behavior of the GNNQQNY peptide on the surface of mica and highly oriented pyrolytic graphite through tailoring the self-assembly conditions. Various factors, such as the type of dissolvent, peptide concentration, pH value, and evaporation period on the formation of peptide nanofibers and nanoribbons with single- and bi-directional arrays are investigated. It is found that the creation of peptide nanoribbons on both mica and HOPG can be achieved effectively through adjusting and optimizing the experimental parameters. Based on the obtained results, the self-assembly and formation mechanisms of peptide nanoribbons on both material interfaces are discussed. It is expected that the findings obtained in this study will inspire the design of motif-specific peptides with high binding affinity towards materials and mediate the green synthesis of peptide-based bionanomaterials with unique function and application potential.

Recent advances in multifunctional nanomaterials for photothermal-enhanced Fenton-based chemodynamic tumor therapy

Photothermal (PT)-enhanced Fenton-based chemodynamic therapy (CDT) has attracted a significant amount of research attention over the last five years as a highly effective, safe, and tumor-specific nanomedicine-based therapy. CDT is a new emerging nanocatalyst-based therapeutic strategy for the in situ treatment of tumors via the Fenton reaction or Fenton-like reaction, which has got fast progress in recent years because of its high specificity and activation by endogenous substances. A variety of multifunctional nanomaterials such as metal-, metal oxide-, and metal-sulfide-based nanocatalysts have been designed and constructed to trigger the in situ Fenton or Fenton-like reaction within the tumor microenvironment (TME) to generate highly cytotoxic hydroxyl radicals (•OH), which is highly efficient for the killing of tumor cells. However, research is still required to enhance the curative outcomes and minimize its side effects. Specifically, the therapeutic efficiency of certain CDTs is still hindered by the TME, including low levels of endogenous hydrogen peroxide (H2O2), overexpression of reduced glutathione (GSH), and low catalytic efficacy of Fenton or Fenton-like reactions (pH 5.6-6.8), which makes it difficult to completely cure cancer using monotherapy. For this reason, photothermal therapy (PTT) has been utilized in combination with CDT to enhance therapeutic efficacy. More interestingly, tumor heating during PTT not only causes damage to the tumor cells but can also accelerate the generation of •OH via the Fenton and Fenton-like reactions, thus enhancing the CDT efficacy, providing more effective cancer treatment when compared with monotherapy. Currently, synergistic PT-enhanced CDT using multifunctional nanomaterials with both PT and chemodynamic properties has made enormous progress in cancer theranostics. However, there has been no comprehensive review on this subject published to date. In this review, we first summarize the recent progress in PT-enhanced Fenton-based CDT for cancer treatment. We then discuss the potential and challenges in the future development of PT-enhanced Fenton-based nanocatalytic tumor therapy for clinical application.

Tumor-targeted Biomimetic Nanoplatform Precisely Integrate Photodynamic Therapy and Autophagy Inhibiton for Collaborative Treatment of Oral Cancer

Oral cancer is a common malignant tumor in the maxillofacial regions. Surgical resection is the preferred treatment, but severe functional impairment after surgery forces us to look for noninvasive treatments....

Self-assembling and cellular distribution of a series of transformable peptides

Transformable peptides (TPs) are biomedical materials with unique structures and diverse functionalities that have drawn great interest in material science and nanomedicine. Here, we design a series of TPs with...

Recent progress in Tannic Acid-driven antimicrobial/antifouling surface coating strategies

Medical devices and surgical implants are a necessary part of tissue engineering and regenerative medicines. However, the biofouling and microbial colonization on the implant surface continues to be a major...

Leveraging disulfiram to treat cancer: Mechanisms of action, delivery strategies, and treatment regimens

Disulfiram (DSF) has been used as an alcoholism drug for 70 years. Recently, it has attracted increasing attention owing to the distinguished anticancer activity, which can be further potentiated by the supplementation of Cu²⁺. Although encouraging anticancer results are obtained in lab, the clinical outcomes of oral DSF are not satisfactory, which urges an in-depth understanding of the underlying mechanisms, bottlenecks, and proposal of potential methods to address the dilemma. In this review, a critical summarization of various molecular biological anticancer mechanisms of DSF/Cu²⁺ is provided and the predicament of orally delivering DSF in clinical oncotherapy is explained by the metabolic barriers. We highlight the recent advances in the DSF/Cu²⁺ delivery strategies and the emerging treatment regimens for cancer treatment. Last but not the least, we summarize the clinical trials regarding DSF and make a prospect of DSF/Cu-based cancer therapy.

Targeting drug delivery and efficient lysosomal escape for chemo-photodynamic cancer therapy by a peptide/DNA nanocomplex

A peptide/DNA nanocomplex was developed for the targeted delivery of chemotherapeutics and photosensitizers to cancer cells for efficient combination therapy. The chemotherapeutic drug doxorubicin (DOX) and the photosensitizer 5,10,15,20-tetra-(1-methylpyridine-4-yl)-porphyrin (TMPyP4) were physically incorporated by an aptamer (AS1411)-modified tetrahedral DNA nanostructure, where the tetrahedral DNA and aptamer-induced G-quadruplex provide binding sites of DOX and TMPyP4. The co-loaded 3A-TDN/DT displayed a targeted uptake by HeLa cancer cells through the high affinity and specificity between AS1411 and nucleolin, a protein overexpressed on many types of cancer cells. A polycationic polymer, mPEG-PAsp(TECH), was synthesized to complex with the DNA nanostructure to efficiently escape from lysosomes via the proton sponge effect upon the enhanced internalization by tumor cells. Under the irradiation of 660 nm laser light, TMPyP4 induced an upregulation of intracellular reactive oxygen species, which combined with DOX to fulfill the efficient inhibition of HeLa cells. Our study demonstrated a biocompatible peptide/DNA composite nanoplatform for combinational cancer therapy via the targeted delivery of therapeutic agents and efficient lysosomal escape.

Prospects of Exploring the Metal-Organic Framework for Combating Antimicrobial Resistance

Infectious diseases are a major public health concern globally. Infections caused by pathogens with resistance against commonly used antimicrobial drugs or antibiotics (known as antimicrobial resistance, AMR) are becoming extremely difficult to control. AMR has thus been declared as one of the top 10 global public health threats, as it has very limited solutions. The drying pipeline of effective antibiotics has further worsened the situation. There is no absolute treatment, and the limitations of existing methods warrant further development in antimicrobials. Recent developments in the nanomaterial field present them as promising therapeutics and effective alternative to conventional antibiotics and synthetic drugs. The metal-organic framework (MOF) is a recent addition to the antimicrobial category with superior properties. The MOF exerts antimicrobial action on a wide range of species and is highly biocompatible. Additionally, their porous structures allow the incorporation of biomolecules and drugs for synergistic antimicrobial action. This review provides an inclusive summary of the molecular events responsible for resistance development and current trends in antimicrobials to combat antibiotic resistance and explores the potential role of the MOF in tackling the drug-resistant microbial species.

Strong Penetration-Induced Effective Photothermal Therapy by Exosome-Mediated Black Phosphorus Quantum Dots

Nanocancer medicine, such as photothermal therapy (PTT), as a promising way to solve cancer without side effects, faces a huge biological barrier during the circulation of nanoparticles in the body, including nanobiological interactions in the blood, isolation of nanoparticles in the macrophage system, tumor spillover effect, and especially uneven intratumoral distribution of nanoparticles, which cast a shadow over the hope. To address the problem of intratumoral distribution, an effective photothermal agent is introduced by packaging the black phosphorus quantum dots (BPQDs) into exosome vector (EXO) through electroporation method. With the improving and proper stability for better therapy, the resulting BPQDs@EXO nanospheres (BEs) exhibit good biocompatibility, long circulation time, and excellent tumor targeting ability, hence impressive PTT efficiency evidenced by highly efficient tumor ablation in vivo. Importantly, great permeability on organoids contributed by EXO appears with BEs, which strongly promotes the efficient killing ability. These BP-based nanospheres must promise high clinical potential due to the high PTT efficiency and minimal side effects.

Mitochondria-Targeted Self-Assembly of Peptide-Based Nanomaterials

Mitochondria are well known to serve as the powerhouse for cells and also the initiator for some vital signaling pathways. A variety of diseases are discovered to be associated with the abnormalities of mitochondria, including cancers. Thus, targeting mitochondria and their metabolisms are recognized to be promising for cancer therapy. In recent years, great efforts have been devoted to developing mitochondria-targeted pharmaceuticals, including small molecular drugs, peptides, proteins, and genes, with several molecular drugs and peptides enrolled in clinical trials. Along with the advances of nanotechnology, self-assembled peptide-nanomaterials that integrate the biomarker-targeting, stimuli-response, self-assembly, and therapeutic effect, have been attracted increasing interest in the fields of biotechnology and nanomedicine. Particularly, in situ mitochondria-targeted self-assembling peptides that can assemble on the surface or inside mitochondria have opened another dimension for the mitochondria-targeted cancer therapy. Here, we highlight the recent progress of mitochondria-targeted peptide-nanomaterials, especially those in situ self-assembly systems in mitochondria, and their applications in cancer treatments.

A manganese (II)-based coordinative dendrimer with robust efficiency in intracellular peptide delivery

Peptides have gained increasing interests as drug candidates in modern pharmaceutical industry, however, the development of peptide drugs acting on intracellular targets is limited due to their membrane impermeability. Here, we reported the use of metal-terpyridine based coordinative dendrimer for cytosolic peptide delivery. Among the investigated transition metal ions, Mn²⁺-coordinated polymer showed the highest delivery efficiency due to balanced peptide binding and release. It showed robust efficiency in the delivery of peptides with different charge property and hydrophobicity into various primary cells. The efficiency of Mn²⁺-terpyridine based polymer is superior to cell penetrating peptides such as oligoarginines. The material also delivered an autophagy-inducing peptide derived from Beclin-1 into cells and efficiently induced autophagy in the cells. This study provides a promising alternative to cell penetrating peptides for cytosolic peptide delivery.

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A Mn²⁺/terpyridine based polymer is rationally designed for cytosolic peptide delivery.

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The polymer shows robust efficiency in the delivery of 22 peptides with different properties into various primary cells.

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The polymer delivers an autophagy-inducing peptide derived from Beclin-1 into cells and efficiently induces autophagy.

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This study provides a promising alternative to cell penetrating peptides for cytosolic peptide delivery.

A targeted self-assembling photosensitizer nanofiber constructed by multicomponent coordination

Employing a peptide-based supramolecular photosensitizer nanofiber that combines the flexibility of a self-assembling short peptide and high spatiotemporal precision is a promising approach in photodynamic therapy (PDT). Herein, we developed a versatile multicomponent and multifunctional coordination self-assembling photosensitizer nanofiber based on the combination of a diphenylalanine (FF) short peptide, cell penetrating peptide 44 (CPP44) and 5-(4-aminophenyl)-10,15,20-triphenyl porphine (TPP-NH₂), resulting in CPP44-FF-TPP-NH₂ nanofibers (CFTNFs). Transmission electron microscopy observations showed the filamentous morphology of CFTNFs. Compared with free TPP-NH₂, CFTNFs exhibited a higher cell uptake ability in HepG2 cells and a better tumor targeting ability in in vivo experiments. Furthermore, CFTNFs induced apoptosis and necrosis of more HepG2 cells in vitro and showed higher tumor growth inhibitory activity in vivo. In summary, these results indicated that CFTNFs could lead to greatly enhanced photodynamic treatment efficacy. Moreover, our study provides new opportunities for the development of peptide-based multicomponent coordination self-assembling photosensitizer nanofibers to enhance tumor-specific delivery and the anticancer efficiency.

A mini-review on peptide-based self-assemblies and their biological applications

Peptide-based supramolecular self-assembly from peptide monomers into well-organized nanostructures, has attracted extensive attentions towards biomedical and biotechnological applications in recent decades. This spontaneous and reversible assembly process involving non-covalent bonding interactions can be artificially regulated. In this review, we have elaborated different strategies to modulate the peptide self-assembly through tuning the physicochemical and environmental conditions, includingpH, light, temperature, solvent, and enzyme. Detailed introduction of biological applications and future potential of the peptide-based nano-assemblies will also be given.

A Supramolecular Nanomedicine Based on Bendamustine and MDM2-Targeted D-peptide Inhibitor for Breast Cancer Therapy

Bendamustine (BEN) is a FDA-approved bifunctional DNA-alkylating chemotherapy drug, but it suffers from short half-life, instability, and poor biocompatibility in the clinical application. Due to unique biostability of d-amino acid-containing peptides (D-peptides), constructing D-peptide-small molecule drug conjugates is emerging as a promising strategy for cancer therapy. Here, a high-affinity MDM2-targeted D-peptide (peptide 5) is discovered by applying structure-based drug design (SBDD). Taking the advantages of d-amino acids, a novel self-assembling D-peptide-small molecule drug conjugate (BEN-FF-peptide 5) is developed by simultaneously conjugating small molecule drug BEN and peptide 5 to the self-assembling peptide. In vitro results demonstrate that BEN-FF-peptide 5 exhibits superior cellular uptake ability, good biostability in human serum and strong inhibitory effect on the growth of human breast cancer (MCF-7) cells. In vivo study reveals that BEN-FF-peptide 5 significantly inhibits the growth of MCF-7 cells-derived xenograft in nude mice with no obvious side effects. This work provides a useful strategy to construct D-peptide-small molecule drug conjugates for high-efficacy and low-toxicity cancer therapy.

Fundamental and Clinical Applications of Materials Based on Cancer-Associated Fibroblasts in Cancers

Cancer stromal cells play a role in promoting tumor relapse and therapeutic resistance. Therefore, the current treatment paradigms for cancers are usually insufficient to eradicate cancer cells, and anti-cancer therapeutic strategies targeting stromal cells have been developed. Cancer-associated fibroblasts (CAFs) are perpetually activated fibroblasts in the tumor stroma. CAFs are the most abundant and highly heterogeneous stromal cells, and they are critically involved in cancer occurrence and progression. These effects are due to their various roles in the remodeling of the extracellular matrix, maintenance of cancer stemness, modulation of tumor metabolism, and promotion of therapy resistance. Recently, biomaterials and nanomaterials based on CAFs have been increasingly developed to perform gene or protein expression analysis, three-dimensional (3D) co-cultivation, and targeted drug delivery in cancer treatment. In this review, we systematically summarize the current research to fully understand the relevant materials and their functional diversity in CAFs, and we highlight the potential clinical applications of CAFs-oriented biomaterials and nanomaterials in anti-cancer therapy.

Recent advances in selective photothermal therapy of tumor

Photothermal therapy (PTT), which converts light energy to heat energy, has become a new research hotspot in cancer treatment. Although researchers have investigated various ways to improve the efficiency of tumor heat ablation to treat cancer, PTT may cause severe damage to normal tissue due to the systemic distribution of photothermal agents (PTAs) in the body and inaccurate laser exposure during treatment. To further improve the survival rate of cancer patients and reduce possible side effects on other parts of the body, it is still necessary to explore PTAs with high selectivity and precise treatment. In this review, we summarized strategies to improve the treatment selectivity of PTT, such as increasing the accumulation of PTAs at tumor sites and endowing PTAs with a self-regulating photothermal conversion function. The views and challenges of selective PTT were discussed, especially the prospects and challenges of their clinical applications.

Biological homeostasis-inspired light-excited multistage nanocarriers induce dual apoptosis in tumors

In the microenvironment of an organism, each element always regulates and compensates for each other's defects, finally achieving biostable equilibrium. Herein, inspired by the balance of biological homeostasis and the interconstraint of elements, light-responsive nanoparticle with anti-vascularization and oxygen-supplying ability such like a homeostasis body is constructed by the electrostatic adsorption of reactive oxygen species (ROS)-responsive copolymers with photosensitizers and oxygen donors, which act as the elements of homeostasis body can interact through multistage reactions forming a balance that induces double apoptosis including those caused by the photosensitizer itself and those induced after oxygenation. In this homeostasis body, the element photosensitizer can simultaneously generate hyperthermia and ROS. The former can not only inhibit the growth of blood vessels and promote cell necrosis, but induce the thermally responsive release of oxygen to alleviate tumor hypoxia for enhanced PDT. And the latter will induce rapid depolymerization of nanoparticles, promote the penetration and finally induce double apoptosis through multistage reactions. Immunofluorescence data further demonstrate that the nanoparticles significantly alleviated tumor hypoxia upon photoexcitation. Thus, such nanoparticles with multistage synergistic effects have demonstrated excellent effects in achieving biostable equilibrium to induce dual apoptosis and may also be a good strategy in hypoxic tumors therapy.

Induction of Apoptotic Temperature in Photothermal Therapy under Various Heating Conditions in Multi-Layered Skin Structure

Recently, photothermal therapy has attracted attention as an alternative treatment to conventional surgical techniques because it does not lead to bleeding and patients quickly recover after treatment compared to incisional surgery. Photothermal therapy induces tumor cell death through an increase in the temperature using the photothermal effect, which converts light energy into thermal energy. This study was conducted to perform numerical analysis based on heat transfer to induce apoptosis of tumor tissue under various heating conditions in photothermal therapy. The Monte Carlo method was applied to evaluate a multi-layered skin structure containing squamous cell carcinoma. Tissue-equivalent phantom experiments verified the numerical model. Based on the effective apoptosis retention ratio, the numerical analysis results showed the quantitative correlation for the laser intensity, volume fraction of gold nanorods injected into the tumor, and cooling time. This study reveals optimal conditions for maximizing apoptosis within tumor tissue while minimizing thermal damage to surrounding tissues under various heating conditions. This approach may be useful as a standard treatment when performing photothermal therapy.

Self-assembly of amino acids toward functional biomaterials

Biomolecules, such as proteins and peptides, can be self-assembled. They are widely distributed, easy to obtain, and biocompatible. However, the self-assembly of proteins and peptides has disadvantages, such as difficulty in obtaining high quantities of materials, high cost, polydispersity, and purification limitations. The difficulties in using proteins and peptides as functional materials make it more complicate to arrange assembled nanostructures at both microscopic and macroscopic scales. Amino acids, as the smallest constituent of proteins and the smallest constituent in the bottom-up approach, are the smallest building blocks that can be self-assembled. The self-assembly of single amino acids has the advantages of low synthesis cost, simple modeling, excellent biocompatibility and biodegradability in vivo. In addition, amino acids can be assembled with other components to meet multiple scientific needs. However, using these simple building blocks to design attractive materials remains a challenge due to the simplicity of the amino acids. Most of the review articles about self-assembly focus on large molecules, such as peptides and proteins. The preparation of complicated materials by self-assembly of amino acids has not yet been evaluated. Therefore, it is of great significance to systematically summarize the literature of amino acid self-assembly. This article reviews the recent advances in amino acid self-assembly regarding amino acid self-assembly, functional amino acid self-assembly, amino acid coordination self-assembly, and amino acid regulatory functional molecule self-assembly.

Formation of β-Lactoglobulin Self-Assemblies via Liquid-Liquid Phase Separation for Applications beyond the Biological Functions

Proteins are like miracle machines, playing important roles in living organisms. They perform vital biofunctions by further combining together and/or with other biomacromolecules to form assemblies or condensates such as membraneless organelles. Therefore, studying the self-assembly of biomacromolecules is of fundamental importance. In addition to their biological activities, protein assemblies also exhibit extra properties that enable them to achieve applications beyond their original functions. Herein, this study showed that in the presence of monosaccharides, ethylene glycols, and amino acids, β-lactoglobulin (β-LG) can form assemblies with specific structures, which were highly reproducible. The mechanism of the assembly process was studied through multi-scale observations and theoretical analysis, and it was found that the assembling all started from the formation of solute-rich liquid droplets via liquid-liquid phase separation (LLPS). These droplets then combined together to form condensates with elaborate structures, and the condensates finally evolved to form assemblies with various morphologies. Such a mechanism of the assembly is valuable for studying the assembly processes that frequently occur in living organisms. Detailed studies concerning the properties and applications of the obtained β-LG assemblies showed that the assemblies exhibited significantly better performances than the protein itself in terms of autofluorescence, antioxidant activity, and metal ion absorption, which indicates broad applications of these assemblies in bioimaging, biodetection, biodiagnosis, health maintenance, and pollution treatment. This study revealed that biomacromolecules, especially proteins, can be assembled via LLPS, and some unexpected application potentials could be found beyond their original biological functions.

Dynamic nanoassemblies of nanomaterials for cancer photomedicine

Photomedicine has long been used for treating cancerous diseases. With advances in chemical and material sciences, various types of light-activated photosensitizers (PSs) have been developed for effective photodynamic therapy (PDT) and photothermal therapy (PTT). However, conventional organic/inorganic materials-based PSs lack disease recognition capability and show limited therapeutic effects in addition to side effects. Recently, intelligent dynamic nanoassemblies that are activated in a tumor environment have been extensively researched to target diseased tissues more effectively, for increasing therapeutic effectiveness while minimizing side effects. This paper presents the latest dynamic nanoassemblies for effective PDT or PTT and combination phototherapies, including immunotherapy and image-guided therapy. Dynamic self-assembly exhibits great potential for clinical translation in diagnosis and treatment through its integrated versatility. Nanoassemblies based on multidisciplinary technology are a promising technique for treating incurable cancerous diseases in the future.

Biodegradable Hypocrellin B nanoparticles coated with neutrophil membranes for hepatocellular carcinoma photodynamics therapy effectively via JUNB/ROS signaling

Hepatocellular carcinoma (HCC) is an inflammation-induced and chemotherapy-resistant common liver cancer, and a major cause of death. Some natural products have been found to be used as photosensitizers in photodynamic therapy of HCC. Due to its specific molecular structure diversities and biological activities, current status of HCC treatment with nature production remains unsatisfactory, owing largely to the toxicity, side effect and inefficiency to drug targeting. Herein, we show a nanoparticle-based broad-spectrum anti-inflammatory strategy that naïve neutrophil membrane-coated PLGA nanoparticles (NM-HB NPs) were constructed for synchronous nearinfrared fluorescence (NIR FL) imaging and photodynamic therapy (PDT) for HCC. Moreover, NM-HB NPs inhibited the expression of JUNB and promoted the ROS production. JUNB depletion enhanced the anti-HCC effect of NM-HB NPs. Importantly, it was shown that NM-HB NPs are well targeted to the tumor site and overcomes the blood circulation and immune elimination in vivo and vitro. In a mouse model of HCC, the neutrophil membrane-coated nanoparticles (NM-HB NPs) show significant therapeutic efficacy by PDT and suppressing tumor tissue increase. All results demonstrated that NM coated HB NPs representing a viable and effective treatment option for HCC.

Noncanonical Amino Acids for Hypoxia-Responsive Peptide Self-Assembly and Fluorescence

Design of endogenous stimuli-responsive amino acids allows for precisely modulating proteins or peptides under a biological microenvironment and thereby regulating their performance. Herein we report a noncanonical amino acid 2-nitroimidazol-1-yl alanine and explore its functions in creation of the nitroreductase (NTR)-responsive peptide-based supramolecular probes for efficient hypoxia imaging. On the basis of the reduction potential of the nitroimidazole unit, the amino acid was synthesized via the Mitsunobu reaction between 2-nitroimidazole and a serine derivate. We elucidated the relationship between the NTR-responsiveness of the amino acid and the structural feature of peptides involving a series of peptides. This eventually facilitates development of aromatic peptides undergoing NTR-responsive self-assembly by rationally optimizing the sequences. Due to the intrinsic role of 2-nitroimidazole in the fluorescence quench, we created a morphology-transformable supramolecular probe for imaging hypoxic tumor cells based on NTR reduction. We found that the resulting supramolecular probes penetrated into solid tumors, thus allowing for efficient fluorescence imaging of tumor cells in hypoxic regions. Our findings demonstrate development of a readily synthesized and versatile amino acid with exemplified properties in creating fluorescent peptide nanostructures responsive to a biological microenvironment, thus providing a powerful toolkit for synthetic biology and development of novel biomaterials.

Supramolecular peptide nano-assemblies for cancer diagnosis and therapy: from molecular design to material synthesis and function-specific applications

Peptide molecule has high bioactivity, good biocompatibility, and excellent biodegradability. In addition, it has adjustable amino acid structure and sequence, which can be flexible designed and tailored to form supramolecular nano-assemblies with specific biomimicking, recognition, and targeting properties via molecular self-assembly. These unique properties of peptide nano-assemblies made it possible for utilizing them for biomedical and tissue engineering applications. In this review, we summarize recent progress on the motif design, self-assembly synthesis, and functional tailoring of peptide nano-assemblies for both cancer diagnosis and therapy. For this aim, firstly we demonstrate the methodologies on the synthesis of various functional pure and hybrid peptide nano-assemblies, by which the structural and functional tailoring of peptide nano-assemblies are introduced and discussed in detail. Secondly, we present the applications of peptide nano-assemblies for cancer diagnosis applications, including optical and magnetic imaging as well as biosensing of cancer cells. Thirdly, the design of peptide nano-assemblies for enzyme-mediated killing, chemo-therapy, photothermal therapy, and multi-therapy of cancer cells are introduced. Finally, the challenges and perspectives in this promising topic are discussed. This work will be useful for readers to understand the methodologies on peptide design and functional tailoring for highly effective, specific, and targeted diagnosis and therapy of cancers, and at the same time it will promote the development of cancer diagnosis and therapy by linking those knowledges in biological science, nanotechnology, biomedicine, tissue engineering, and analytical science.

Peptide-Assisted Nucleic Acid Delivery Systems on the Rise

Concerns associated with nanocarriers' therapeutic efficacy and side effects have led to the development of strategies to advance them into targeted and responsive delivery systems. Owing to their bioactivity and biocompatibility, peptides play a key role in these strategies and, thus, have been extensively studied in nanomedicine. Peptide-based nanocarriers, in particular, have burgeoned with advances in purely peptidic structures and in combinations of peptides, both native and modified, with polymers, lipids, and inorganic nanoparticles. In this review, we summarize advances on peptides promoting gene delivery systems. The efficacy of nucleic acid therapies largely depends on cell internalization and the delivery to subcellular organelles. Hence, the review focuses on nanocarriers where peptides are pivotal in ferrying nucleic acids to their site of action, with a special emphasis on peptides that assist anionic, water-soluble nucleic acids in crossing the membrane barriers they encounter on their way to efficient function. In a second part, we address how peptides advance nanoassembly delivery tools, such that they navigate delivery barriers and release their nucleic acid cargo at specific sites in a controlled fashion.

Self-Assembly of Peptide Hierarchical Helical Arrays with Sequence-Encoded Circularly Polarized Luminescence

Self-assembled peptide materials with sequence-encoded properties have attracted great interest. Despite their intrinsic chirality, the generation of circularly polarized luminescence (CPL) based on the self-assembly of simple peptides has been rarely reported. Here, we report the self-assembly of peptides into hierarchical helical arrays (HHAs) with controlled supramolecular handedness. The HHAs can emit full-color CPL signals after the incorporation of various achiral fluorescent molecules, and the g_lum value is 40 times higher than that of the CPL signal from the solutions. By simply changing the amino acid sequence of the peptides, CPL signals with opposite handedness can be generated within the HHAs. The peptide HHAs can provide hydrophobic pockets to accommodate the fluorescent molecules with helical arrangement through strong aromatic stacking interactions, which are responsible for the CPL signals. This work provides a pathway to construct highly ordered chiral materials, which have broad applications in the chiroptical field.

Mitochondria-targeting and ROS-sensitive smart nanoscale supramolecular organic framework for combinational amplified photodynamic therapy and chemotherapy

Owing to their reversibly dynamic features, and the regularity of their architectures, supramolecular organic frameworks (SOFs) have attracted attention as new porous materials. Herein, we propose a smart SOF platform for enhanced photodynamic therapy, where the SOF with a superior mitochondria-targeting capability could be cleaved by reactive oxygen species (ROS) produced by itself for highly enhancing PDT. Moreover, it can further work as a platform for carrying chemo-therapeutic drug doxorubicin for synergistic chemo-photodynamic therapy. The SOF is constructed by combining a tetra-β-cyclodextrin-conjugated porphyrin photosensitizer and a ROS-sensitive thioketal linked adamantane dimer utilizing a host-guest supramolecular strategy. The unique supramolecular framework not only completely resolves the aggregation caused quenching of porphyrin photosensitizers but also endows them with significantly enhanced water-solubility. The in vitro and in vivo results demonstrate that the SOF could be targeted onto mitochondria by confocal imaging, and dissociated by ROS generated by itself, leading to autonomous release of porphyrin photosensitizers and DOX for high anti-cancer activity. It is believed that the strategy using a SOF has the potential of being used to construct versatile agents for combined therapies. STATEMENT OF SIGNIFICANCE: Photosensitizers are the essential element in photodynamic therapy. However, typical photosensitizers commonly encounter poor water-solubility, non-specific tumor-targeting, aggregation-caused quenching (ACQ), which seriously reduce PDT efficacy. A mitochondria-targeting and ROS-sensitive supramolecular organic framework (SOF) is designed for photodynamic therapy in cancer treatment, which could completely overcome the bottleneck in the applications of photosensitizers (PSs). The SOF is constructed by combining a tetra-β-cyclodextrin-conjugated porphyrin photosensitizer and a ROS-sensitive thioketal linked adamantane dimer unit utilizing a host-guest supramolecular strategy. The unique supramolecular framework not only completely resolves the aggregation caused quenching of porphyrin photosensitizers but also endows them with significantly enhanced water-solubility. Moreover, the SOF can be readily functionalized to incorporate the anti-cancer agent Doxorubicin and mitochondria targeting molecules through respective physical encapsulation and host-guest interactions.

Metal-Coordinated Supramolecular Self-Assemblies for Cancer Theranostics

Metal-coordinated supramolecular nanoassemblies have recently attracted extensive attention as materials for cancer theranostics. Owing to their unique physicochemical properties, metal-coordinated supramolecular self-assemblies can bridge the boundary between traditional inorganic and organic materials. By tailoring the structural components of the metal ions and binding ligands, numerous multifunctional theranostic nanomedicines can be constructed. Metal-coordinated supramolecular nanoassemblies can modulate the tumor microenvironment (TME), thus facilitating the development of TME-responsive nanomedicines. More importantly, TME-responsive organic-inorganic hybrid nanomaterials can be constructed in vivo by exploiting the metal-coordinated self-assembly of a variety of functional ligands, which is a promising strategy for enhancing the tumor accumulation of theranostic molecules. In this review, recent advancements in the design and fabrication of metal-coordinated supramolecular nanomedicines for cancer theranostics are highlighted. These supramolecular compounds are classified according to the order in which the coordinated metal ions appear in the periodic table. Furthermore, the prospects and challenges of metal-coordinated supramolecular self-assemblies for both technical advances and clinical translation are discussed. In particular, the superiority of TME-responsive nanomedicines for in vivo coordinated self-assembly is elaborated, with an emphasis on strategies that enhance the accumulation of functional components in tumors for an ideal theranostic outcome.

Selective thermotherapy of tumor by self-regulating photothermal conversion system

One major challenge of photothermal therapy (PTT) is achieving thermal ablation of the tumor without damaging the normal cells and tissues. Here, we designed a self-regulating photothermal conversion system for selective thermotherapy based on self-assembling gold nanoparticles (S-AuNPs) and investigated the selectivity effect using a novel home-made in vitro selective photothermal transformation model and an in vivo skin damaging assessment model. In the in vitro selective photothermal transformation model, laser irradiation selectively increased the temperature of the internal microenvironment (pH 5.5) and resulted in an obvious temperature difference (ΔT ≥ 5 °C) with that of the external environment (pH 7.4). More importantly, in the in vivo skin damaging assessment model, S-AuNPs achieved good tumor inhibition without damaging the normal skin tissue compared with the conventional photothermal material. This work provides not only a novel validation protocol for tumor thermotherapy to achieve the biosafety of specifically killing tumor cells and normal tissue but also an evaluation methodology for other precise therapy for cancers.

A porphysome-based photodynamic O2 economizer for hypoxic tumor treatment by inhibiting mitochondrial respiration

A porphysome-based photodynamic O2 economizer (P-PAT) is prepared for hypoxic tumor therapy. The self-assembled porphyrin bilayers of P-PAT possess high loading capacity to atovaquone (ATO) (nearly 70%), which could restrain mitochondrial respiration to relieve hypoxia and enhance photodynamic therapy.