Fabrication of soy protein nanoparticles based on metal-phenolic networks for stabilization of nano-emulsions delivery system

The use of soy protein isolate (SPI) nanoparticles as a stabilizer in nano-emulsion systems has garnered significant interest. While metal-phenolic networks (MPNs) have been explored for their multifunctional surface modification capabilities, their integration with food protein-based delivery systems remains less explored. In this study, we attempt to develop a novel strategy to encapsulate cinnamaldehyde using MPNs (EGCG-Fe3+) with self-assembling soy protein nanoparticles (SE-Fe NPs) as a stabilizer for nano-emulsions. UV, Raman, and X-ray photoelectron spectroscopy analyses demonstrated that SE-Fe NPs were generated through metal-phenolic coordination and covalent interactions. SE-Fe NPs had a narrower particle size distribution and enhanced radical scavenging (up to 3.35-fold), as well as thermal stability. Furthermore, the smaller droplet size, higher modulus, higher cinnamaldehyde encapsulation efficiency (from 63.5% to 84.2%), and improved bio-accessibility of SE-Fe NPs stabilized nano-emulsions delivery system demonstrated in this study shows promising future applications in the food industry.

Robust reactive oxygen species modulator hitchhiking yeast microcapsules for colitis alleviation by trilogically intestinal microenvironment renovation

Ulcerative colitis (UC) is characterized by chronic inflammatory processes of the intestinal tract of unknown origin. Current treatments lack understanding on how to effectively alleviate oxidative stress, relieve inflammation, as well as modulate gut microbiota for maintaining intestinal homeostasis synchronously. In this study, a novel drug delivery system based on a metal polyphenol network (MPN) was constructed via metal coordination between epigallocatechin gallate (EGCG) and Fe3+. Curcumin (Cur), an active polyphenolic compound, with distinguished anti-inflammatory activity was assembled and encapsulated into MPN to generate Cur-MPN. The obtained Cur-MPN could serve as a robust reactive oxygen species modulator by efficiently scavenging superoxide radical (O2•-) as well as hydroxyl radical (·OH). By hitchhiking yeast microcapsule (YM), Cur-MPN was then encapsulated into YM to obtain CM@YM. Our findings demonstrated that CM@YM was able to protect Cur-MPN to withstand the harsh gastrointestinal environment and enhance the targeting and retention abilities of the inflamed colon. When administered orally, CM@YM could alleviate DSS-induced colitis with protective and therapeutic effects by scavenging ROS, reducing pro-inflammatory cytokines, and regulating the polarization of macrophages to M1, thus restoring barrier function and maintaining intestinal homeostasis. Importantly, CM@YM also modulated the gut microbiome to a favorable state by improving bacterial diversity and transforming the compositional structure to an anti-inflammatory phenotype as well as increasing the content of short-chain fatty acids (SCFA) (such as acetic acid, propionic acid, and butyric acid). Collectively, with excellent biocompatibility, our findings indicate that synergistically regulating intestinal microenvironment will be a promising approach for UC.

Development of interpenetrating network hydrogels: Enhancing the release and bioaccessibility of green tea polyphenols

Green Tea polyphenols (GTP) are important bioactive compounds with excellent physiological regulation functions. However, they are easily destroyed by the gastric environment during digestion. In this work, a sodium alginate (SA)-gellan gum (GG) interpenetrating network (IPN) hydrogel was synthesized to protect and delivery GTP. The ratio of SA/GG significantly affects the network structure of IPN hydrogels and the performance of delivering GTP. The hydrogel formed by interpenetrating 20 % GG with 80 % SA as the main network had the highest water uptake (55 g/g), holding capacity (950 mg/g), and freeze-thaw stability, with springiness reaching 0.933 and hardness reaching 1300 g, which due to the filling effect and non-covalent interaction. Rheological tests showed that the crosslink density of IPN hydrogel in SA-dominated network was improved by the addition of GG to make it better bound to GTP, and the higher water uptake meant that the system could absorb more GTP-containing solution. This IPN hydrogel maintained 917.3 mg/g encapsulation efficiency at the highest loading capacity (1080 mg/g) in tests as delivery system. In in vitro digestion simulations, owing to the pH responsiveness, the IPN hydrogel reduced the loss of GTP in gastric fluid, achieving a bioaccessibility of 71.6 % in the intestinal tract.

Metal-Phenolic Nanocapsules with Photothermal Antibacterial and Ros Scavenging Ability for Diabetic Wound Healing

The presence of bacteria in diabetic wounds not only leads to the formation of biofilms but also triggers oxidative stress and inflammatory responses, which hinder the wound-healing process. Therefore, it is imperative to formulate a comprehensive strategy that can proficiently eliminate bacteria and enhance the wound microenvironment. Herein, this work develops multifunctional metal-phenolic nanozymes (TA-Fe/Cu nanocapsules), wherein the one-pot coordination of tannic acid (TA)and Fe3+/Cu2+ using a self-sacrificial template afforded hollow nanoparticles (NPs) with exceptional photothermal and reactive oxygen species scavenging capabilities. After photothermal disruption of the biofilms, TA-Fe/Cu NPs autonomously capture bacteria through hydrogen bonding interactions with peptidoglycans (the bacterial cell wall component), ultimately bolstering the bactericidal efficacy. Furthermore, these NPs exhibit peroxidase-like enzymatic activity, efficiently eliminating surplus hydrogen peroxide in the vicinity of the wound and mitigating inflammatory responses. As the wound transitions into the remodeling phase, the presence of Cu2+ stimulates vascular migration and regeneration, expediting the wound-healing process. This study innovatively devises a minimalist approach to synthesize multifunctional metal-phenolic nanozymes integrating potent photothermal antibacterial activity, bacterial capture, anti-inflammatory, and angiogenesis properties, showcasing their great potential for diabetic wound treatment.

Enhanced therapeutic efficacy of doxorubicin against multidrug-resistant breast cancer with reduced cardiotoxicity

Doxorubicin (DOX), a commonly used anti-cancer drug, is limited by its cardiotoxicity and multidrug resistance (MDR) of tumor cells. Epigallocatechin gallate (EGCG), a natural antioxidant component, can effectively reduce the cardiotoxicity of DOX. Meanwhile, EGCG can inhibit the expression of P-glycoprotein (P-gp) and reverse the MDR of tumor cells. In this study, DOX is connected with low molecular weight polyethyleneimine (PEI) via hydrazone bond to get the pH-sensitive PEI-DOX, which is then combined with EGCG to prevent the cardiotoxicity of DOX and reverse the MDR of cancer cells. In addition, folic acid (FA) modified polyethylene glycol (PEG) (PEG-FA) is added to get the targeted system PEI-DOX/EGCG/FA. The MDR reversal and targeting ability of PEI-DOX/EGCG/FA is performed by cytotoxicity and in vivo anti-tumor activity on multidrug resistant MCF-7 cells (MCF-7/ADR). Additionally, we investigate the anti-drug resistant mechanism by Western Blot. The ability of EGCG to reduce DOX cardiotoxicity is confirmed by cardiotoxicity assay. In conclusion, PEI-DOX/EGCG/FA can inhibit the expression of P-gp and reverse the MDR in tumor cells. It also shows the ability of remove oxygen free radicals effectively to prevent the cardiotoxicity of DOX.

Polyphenol-Based Nanosystems for Next-Generation Cancer Therapy: Multifunctionality, Design, and Challenges

With the continuous updating of cancer treatment methods and the rapid development of precision medicine in recent years, there are higher demands for advanced and versatile drug delivery systems. Scientists are committed to create greener and more effective nanomedicines where the carrier is no longer limited to a single function of drug delivery. Polyphenols, which can act as both active ingredients and fundamental building blocks, are being explored as potential multifunctional carriers that are efficient and safe for design purposes. Due to their intrinsic anticancer activity, phenolic compounds have shown surprising expressiveness in ablation of tumor cells, overcoming cancer multidrug resistance (MDR), and enhancing immunotherapeutic efficacy. This review provides an overview of recent advances in the design, synthesis, and application of versatile polyphenol-based nanosystems for cancer therapy in various modes. Moreover, the merits of polyphenols and the challenges for their clinical translation are also discussed, and it is pointed out that the novel polyphenol delivery system requires further optimization and validation.

Polyphenol-Based Nanoparticles: A Promising Frontier for Enhanced Colorectal Cancer Treatment

Colorectal cancer (CRC) poses a significant challenge in healthcare, necessitating the exploration of novel therapeutic strategies. Natural compounds such as polyphenols with inherent anticancer properties have gained attention as potential therapeutic agents. This review highlights the need for novel therapeutic approaches in CRC, followed by a discussion on the synthesis of polyphenols-based nanoparticles. Various synthesis techniques, including dynamic covalent bonding, non-covalent bonding, polymerization, chemical conjugation, reduction, and metal-polyphenol networks, are explored. The mechanisms of action of these nanoparticles, encompassing passive and active targeting mechanisms, are also discussed. The review further examines the intrinsic anticancer activity of polyphenols and their enhancement through nano-based delivery systems. This section explores the natural anticancer properties of polyphenols and investigates different nano-based delivery systems, such as micelles, nanogels, liposomes, nanoemulsions, gold nanoparticles, mesoporous silica nanoparticles, and metal-organic frameworks. The review concludes by emphasizing the potential of nanoparticle-based strategies utilizing polyphenols for CRC treatment and highlights the need for future research to optimize their efficacy and safety. Overall, this review provides valuable insights into the synthesis, mechanisms of action, intrinsic anticancer activity, and enhancement of polyphenols-based nanoparticles for CRC treatment.

Hierarchical camellia-like metal–organic frameworks via a bimetal competitive coordination combined with alkaline-assisted strategy for boosting selective fluoride removal from brick tea

Developing an efficient and easy scale-up adsorbent with excellent fluoride adsorption and selectivity from brick tea is urgently desired. However, the separation of fluoride from tea is particularly challenging due to it contains abundant active compounds. Herein, we report ultrahigh fluoride adsorption from brick tea by a hierarchical camellia-like bimetallic metal-organic frameworks (MOFs). The hierarchical camellia-like Ca₂Al₁Fu is fabricated via a Ca/Al competitive coordination combined with alkaline-assisted strategy to tailor the morphology and porous structure. Subsequently, we systematically explore how the kinetic, thermodynamic, pH, and coexisting ions parameters employed during fluoride adsorption influence the resulting uptake behavior of Ca₂Al₁Fu. Further, sensory evaluation of the tea after adsorption is explored to determine the optimal dose that makes Ca₂Al₁Fu as a practical adsorbent for application. Importantly, the fluoride adsorption capacity of optical CaAlFu with mixed CaAl metals molar ratio of 2:1 is 3.15 and 2.11 times higher than that of pristine CaFu and AlFu, respectively. Theoretical results reveal that the boosting selective fluoride removal can be ascribed to the specific interactions between fluoride and CaAl coordinatively unsaturated bimetallic centers. These results present an effective design strategy for the construction of bimetallic MOFs with hierarchically porous structures for broad prospect in adsorption-based applications.

In vitro biological evaluation of epigallocatechin gallate (EGCG) release from three-dimensional printed (3DP) calcium phosphate bone scaffolds

Three-dimensional printed (3DP) tricalcium phosphate (TCP) scaffolds can guide bone regeneration, especially for patient-specific defect repair applications in low-load bearing sites. Epigallocatechin gallate (EGCG), a green tea compound, has gained attention as a safer alternative treatment for bone disorders. The 3DP TCP scaffold is designed for localized EGCG delivery, which can enhance in vitro osteogenic ability, anti-osteoclastogenic activity, vascularization formation, and chemoprevention. In the cocultures of human bone marrow-derived mesenchymal stem cells (hMSCs) and monocytes (THP-1), EGCG release enhances osteogenic differentiation of hMSCs at day 16 compared to the control; this is indicated by a 2.8- and 4.0-fold upregulation of Runt-related transcription factor 2 (Runx2) and bone gamma-carboxyglutamic acid-containing protein (BGLAP), the early and late osteoblast differentiation marker expressions. However, EGCG significantly downregulates the receptor activator of nuclear factor-κB ligand (RANKL) expression by 7.0-fold, indicating that EGCG suppresses RANKL-induced osteoclast maturation. EGCG also stimulates endothelial tube formation at as early as 3 hours when human umbilical vein endothelial cells (HUVECs) grow on Matrigel. It reduces human osteosarcoma MG-63 cell viability by 66% compared to the control at day 11. An in vitro release kinetics study demonstrates that EGCG shows a ∼64% release within a day followed by a sustained release in the physiological environment (pH 7.4) because its phenolic hydroxyl groups are easily deprotonated at physiological pH. These findings contribute to developing a multifunctional scaffold for the treatment of low load-bearing patient-specific bone defects after trauma and tumor excision.

Stimuli-Responsive Gene Delivery Nanocarriers for Cancer Therapy

Gene therapy provides a promising approach in treating cancers with high efficacy and selectivity and few adverse effects. Currently, the development of functional vectors with safety and effectiveness is the intense focus for improving the delivery of nucleic acid drugs for gene therapy. For this purpose, stimuli-responsive nanocarriers displayed strong potential in improving the overall efficiencies of gene therapy and reducing adverse effects via effective protection, prolonged blood circulation, specific tumor accumulation, and controlled release profile of nucleic acid drugs. Besides, synergistic therapy could be achieved when combined with other therapeutic regimens. This review summarizes recent advances in various stimuli-responsive nanocarriers for gene delivery. Particularly, the nanocarriers responding to endogenous stimuli including pH, reactive oxygen species, glutathione, and enzyme, etc., and exogenous stimuli including light, thermo, ultrasound, magnetic field, etc., are introduced. Finally, the future challenges and prospects of stimuli-responsive gene delivery nanocarriers toward potential clinical translation are well discussed. The major objective of this review is to present the biomedical potential of stimuli-responsive gene delivery nanocarriers for cancer therapy and provide guidance for developing novel nanoplatforms that are clinically applicable.

An Magnetic-Targeting Nano-Diagnosis and Treatment Platform for TNBC

Purpose

In this experiment, we constructed a magnetic targeting nano-diagnosis and treatment platform of doxorubicin (DOX) combined with iron nanoparticles, and explored their application value and mechanism in the treatment of Triple Negative Breast Cancer (TNBC), as well as its new diagnosis and treatment mode in Magnetic Resonance Imaging (MRI).

Patients and Methods

Hollow mesoporous nanoparticles (HFON) were synthesized by solvothermal method, and loaded the drug DOX (DOX@HFON) to treat TNBC. The experiments in vivo and in vitro were carried out according to the characteristics of the materials. In vitro experiments, the killing effect of the drug on cells was verified by cell viability CCK8, ROS generation level, LPO evaluation and flow cytometry; the MRI effect and targeted anti-tumor therapy effect were studied by in vivo experiments; then the tumor tissue sections were detected by Ki-67, CD31, ROS, LPO and TUNEL immunofluorescence detection; H&E staining and blood biochemical tests were used to evaluate the biosafety of the materials.

Results

Through a series of characterization tests, it is confirmed that the nano-materials prepared in this experiment have positive drug loading properties. MDA-MB-231 cells had great phagocytic ability to DOX@HFON under Confocal Laser Scanning Microscope (CLSM). Experiments in vitro confirmed that DOX and Fe were released and concentrated in cells, and a large number of ROS production and induction of LPO were detected by DCFH-DA and C11-BODIPY probes in cells. Apoptosis experiments further confirmed that DOX@HFON induced apoptosis, autophagy and ferroptosis. In the vivo experiment, the anti-tumor therapy effect of MAGNET@DOX@HFON group was the most significant, and in MRI also proved that the drug had great tendency and imaging ability in tumor tissue.

Conclusion

The new magnetic targeting nano-diagnosis and treatment platform prepared in this experiment is expected to become a new treatment model for TNBC.

Valorization of potato peel waste: Recovery of p-hydroxy benzoic acid (antioxidant) through molecularly imprinted solid-phase extraction

Solid waste management of the potato peels, generated during the processing of potatoes, can be done sustainably by adding value to the peel waste. Peels contains polyphenols, which serve as a defense mechanism against foreign pathogens in plants and have a variety of pharmacological properties such as antioxidant and anti-carcinogenic properties. However, specific segregation of any one polyphenol from waste can be challenging due to its complex matrix and low concentration of the targeted polyphenol. This work presents a way to combat this challenge through molecularly imprinted solid-phase extraction (MISPE) using customized graphene oxide-based molecularly imprinted composite (GOMIP) as sorbent for the selective recovery of p-hydroxy benzoic acid (P-HA) (antioxidant used in food industries), from potato peels for the effective valorization of peels. Various parameters such as flow rate, vacuum manifold pressure, conditioning solvent, washing solvent, and elution solvent were optimized for effective segregation of targeted P-HA. The imprinting factor of 2.14, obtained using breakthrough curves for GOMIP and control (graphene oxide based non-imprinted composite-GONIP) sorbent under optimized condition, indicated the ability of the sorbent GOMIP to recover P-HA from the extract of potato peels. Reusability and selectivity studies were performed for GOMIP sorbent using the real sample [potato peels extract (PPE)]. 77.44% recovery for P-HA was exhibited by the GOMIP sorbent in the MISPE cartridge as determined using HPLC. MISPE with customized GOMIP sorbent can be a sustainable approach to valorize the potato peel solid waste.

Efficient Utilization of Tea Resources through Encapsulation: Dual Perspectives from Core Material to Wall Material

With the high production and consumption of tea around the world, efficient utilization of tea byproducts (tea pruning, tea residues after production, and drinking) is the focus of improving the economy of the tea industry. This review comprehensively discusses the efficient utilization of tea resources by encapsulation from the dual perspectives of core material and wall material. The core material is mainly tea polyphenols, followed by tea oils. The encapsulation system for tea polyphenols includes microcapsules, nanoparticles, emulsions, gels, conjugates, metal-organic frameworks, liposomes, and nanofibers. In addition, it is also diversified for the encapsulation of tea oils. Tea resources as wall materials refer to tea saponins, tea polyphenols, tea proteins, and tea polysaccharides. The application of the tea-based delivery system widely involves functionally fortified food, meat preservation, film, medical treatment, wastewater treatment, and plant protection. In the future, the coencapsulation of tea resources as core materials and other functional ingredients, the precise targeting of these tea resources, and the wide application of tea resources in wall materials need to be focused on. In conclusion, the described technofunctional properties and future research challenges in this review should be followed.

A comprehensive review of nano-delivery system for tea polyphenols: Construction, applications, and challenges

Tea polyphenols (TPs) are important bioactive compounds in tea and have excellent physiological regulation functions. However, the extraction and purification of TPs are key technologies affecting their further application, and the chemical instability, poor bioavailability of TPs are major challenges for researchers. In the past decade, therefore, research and development of advanced carrier systems for the delivery of TPs has been greatly promoted to improve their poor stability and poor bioavailability. In this review, the properties and function of TPs are introduced, and the recent advances in the extraction and purification technologies are systematically summarized. Particularly, the intelligent delivery of TPs via novel nano-carriers is critically reviewed, and the application of TPs nano-delivery system in medical field and food industry is also described. Finally, the main limitations, current challenges and future perspectives are highlighted in order to provide research ideas for exploiting nano-delivery carriers and their application in TPs.

Highly sensitive H2O2-scavenging nano-bionic system for precise treatment of atherosclerosis

In atherosclerosis, chronic inflammatory processes in local diseased areas may lead to the accumulation of reactive oxygen species (ROS). In this study, we devised a highly sensitive H₂O₂-scavenging nano-bionic system loaded with probucol (RPP-PU), to treat atherosclerosis more effectively. The RPP material had high sensitivity to H₂O₂, and the response sensitivity could be reduced from 40 to 10 μmol/L which was close to the lowest concentration of H₂O₂ levels of the pathological environment. RPP-PU delayed the release and prolonged the duration of PU in vivo. In Apolipoprotein E deficient (ApoE^‒/‒) mice, RPP-PU effectively eliminated pathological ROS, reduced the level of lipids and related metabolic enzymes, and significantly decreased the area of vascular plaques and fibers. Our study demonstrated that the H₂O₂-scavenging nano-bionic system could scavenge the abundant ROS in the atherosclerosis lesion, thereby reducing the oxidative stress for treating atherosclerosis and thus achieve the therapeutic goals with atherosclerosis more desirably.

Recent Advances in Metal-Organic-Framework-Based Nanocarriers for Controllable Drug Delivery and Release

Metal-organic frameworks (MOFs) have a good designability, a well-defined pore, stimulus responsiveness, a high surface area, and a controllable morphology. Up to now, various MOFs have been widely used as nanocarriers and have attracted lots of attention in the field of drug delivery and release because of their good biocompatibility and high-drug-loading capacity. Herein, we provide a comprehensive summary of MOF-based nanocarriers for drug delivery and release over the last five years. Meanwhile, some representative examples are highlighted in detail according to four categories, including the University of Oslo MOFs, Fe-MOFs, cyclodextrin MOFs, and other MOFs. Moreover, the opportunities and challenges of MOF-based smart delivery vehicles are discussed. We hope that this review will be helpful for researchers to understand the recent developments and challenges of MOF-based drug-delivery systems.

Chitosan-Polyphenol Conjugates for Human Health

Human health deteriorates due to the generation and accumulation of free radicals that induce oxidative stress, damaging proteins, lipids, and nucleic acids; this has become the leading cause of many deadly diseases such as cardiovascular, cancer, neurodegenerative, diabetes, and inflammation. Naturally occurring polyphenols have tremendous therapeutic potential, but their short biological half-life and rapid metabolism limit their use. Recent advancements in polymer science have provided numerous varieties of natural and synthetic polymers. Chitosan is widely used due to its biomimetic properties which include biodegradability, biocompatibility, inherent antimicrobial activity, and antioxidant properties. However, due to low solubility in water and the non-availability of the H-atom donor, the practical use of chitosan as an antioxidant is limited. Therefore, chitosan has been conjugated with polyphenols to overcome the limitations of both chitosan and polyphenol, along with increasing the potential synergistic effects of their combination for therapeutic applications. Though many methods have been evolved to conjugate chitosan with polyphenol through activated ester-modification, enzyme-mediated, and free radical induced are the most widely used strategies. The therapeutic efficiency of chitosan-polyphenol conjugates has been investigated for various disease treatments caused by ROS that have shown favorable outcomes and tremendous results. Hence, the present review focuses on the recent advancement of different strategies of chitosan-polyphenol conjugate formation with their advantages and limitations. Furthermore, the therapeutic applicability of the combinatorial efficiency of chitosan-based conjugates formed using Gallic Acid, Curcumin, Catechin, and Quercetin in human health has been described in detail.

The Intracellular and Extracellular Microenvironment of Tumor Site: The Trigger of Stimuli-Responsive Drug Delivery Systems

The tumor microenvironment (TME), including intracellular and extracellular microenvironment, contains many biochemical indicators (such as acidity/alkalinity, oxygen content, and enzymatic activity) that are different from the normal physiological environment. These abnormal biochemical indicators can accelerate the heterogeneity of tumors, but on the other hand, they also provide opportunities for the design of intelligent drug delivery systems (DDSs). The TME-responsive DDSs have shown great potential in reducing the side effects of chemotherapy and improving the curative effect of tumors. In this review, the abnormal biochemical indicators of TME are introduced in detail from both the extracellular and intracellular aspects. In view of the various physiological barriers encountered during drug delivery, the strategy of constructing TME-responsive DDSs is discussed. By summarizing the typical research progress, the authors prospect the development of TME-responsive DDS in the future.

ZIF-8 with cationic defects toward efficient 125I2 uptake for in vitro radiotherapy of colon cancer

Introducing 2,3-dimethyl-1H-imidazol-3-ium iodide (Dmim) as a monodentate ligand during the preparation of ZIF-8 yields ZIF-8+(50) and ZIF-8+(38) with cationic ‘missing linker’ defects. ZIF-8+(38) adsorbs 125I2 and the resulting radioactive host-guest...

Polyphenol-Based Paclitaxel Prodrug Self-Assembled Nanoplatform for Tumor Synergistic Therapy

With the development of nanomedicine, studies focus on self-assembled nanoplatforms to reduce the toxicity of paclitaxel (PTX), promote the immune function at low-toxicity PTX, and achieve tumor synergistic therapy. Herein, a new nanoplatform was prepared with self-assembled 5-hydroxydopamine (DA)-PTX@tannic acid (TA)-Fe³⁺ nanoparticles (TDPP NPs) by consolidation of targeted DA-PTX and TA with the assistance of coordination between polyphenols and Fe³⁺. The polyphenol-based TDPP NPs can reduce the toxicity of PTX and thereby realize the in vitro and in vivo synergistic effect against tumors. The low-toxicity TDPP NPs can enhance the expression of CD40 immune protein. Moreover, the TDPP NPs possessed a small size (52.2±4 nm), high drug loading efficiency (95%), and stable pharmacokinetics, ensuring high tumor accumulation of TDPP NPs by enhanced permeability and retention effect. Our work sheds new light on the nanoformulation of PTX with low toxicity and synergistic therapy effect, which may find clinical applications in the future.

Recent Advances in Metal-Phenolic Networks for Cancer Theranostics

Nanomedicine integrates different functional materials to realize the customization of carriers, aiming at increasing the cancer therapeutic efficacy and reducing the off-target toxicity. However, efforts on developing new drug carriers that combine precise diagnosis and accurate treatment have met challenges of uneasy synthesis, poor stability, difficult metabolism, and high cytotoxicity. Metal-phenolic networks (MPNs), making use of the coordination between phenolic ligands and metal ions, have emerged as promising candidates for nanomedicine, most notably through the service as multifunctional theranostic nanoplatforms. MPNs present unique properties, such as rapid preparation, negligible cytotoxicity, and pH responsiveness. Additionally, MPNs can be further modified and functionalized to meet specific application requirements. Here, the classification of polyphenols is first summarized, followed by the introduction of the properties and preparation strategies of MPNs. Then, their recent advances in biomedical sciences including bioimaging and anti-tumor therapies are highlighted. Finally, the main limitations, challenges, and outlooks regarding MPNs are raised and discussed.

Encapsulation of Enzymes in Metal-Phenolic Network Capsules for the Trigger of Intracellular Cascade Reactions

Nanoengineered capsules encapsulated with functional cargos (e.g., enzymes) are of interest for various applications including catalysis, bioreactions, sensing, and drug delivery. Herein, we report a facile strategy to engineer enzyme-encapsulated metal-phenolic network (MPN) capsules using enzyme-loaded zeolitic imidazolate framework nanoparticles (ZIF-8 NPs) as templates, which can be removed in a mild condition (e.g., ethylenediaminetetraacetic acid (EDTA) solution). The capsule size (from 250 nm to 1 μm) and thickness (from 9.8 to 33.7 nm) are well controlled via varying the template size and coating time, respectively. Importantly, MPN capsules encapsulated with enzymes (i.e., glucose oxidase) can trigger the intracellular cascade reaction via the exhaustion of glucose to produce H₂O₂ and subsequently generate toxic hydroxyl radicals (^•OH) based on the Fenton reaction via the reaction between H₂O₂ and iron ions in MPN coatings. The intracellular cascade reaction for the generation of ^•OH is efficient to inhibit cancer cell viability, which is promising for the application in chemodynamic therapy.

Multifunctional carbon monoxide nanogenerator as immunogenic cell death drugs with enhanced antitumor immunity and antimetastatic effect

The limited effect of immune checkpoint blockade (ICB) immunotherapy is subjected to the immuno-suppressive tumor microenvironment (TME). It is still a challenge to reverse the immune-suppressive state in clinical cancer therapy. Immunogenic cell death (ICD) is a way for inducing the therapeutical tumor immune system. In this work, carbon monoxide (CO) gas therapy is used to boost antitumor immunity for tumor control, metastasis and recurrence prevention. Briefly, CO₂-g-C₃N₄-Au@ZIF-8@F127 (CCAZF) is proposed to integrate gas therapy and immunotherapy into a photocatalytic nanogenerator for overcoming the limitations of monotherapy. CCAZF exhibits a highly effective light-controllable release behavior of CO, which gradually aggravates the oxidative stress in tumor cells to induce ICD. With the induction of ICD, CO therapy enhances immune responses and enables efficient immune cells activated. When combined with ICB, CCAZF displays an enhanced immune effect, which mediates the regression of primary and distal tumors. This strategy of in-situ photocatalytic CO therapy furthest avoids the toxicity from CO leakage and provides a new method to design novel ICD inducers.

Multifaceted role of phyto-derived polyphenols in nanodrug delivery systems

As naturally occurring bioactive products, several lines of evidence have shown the potential of polyphenols in the medical intervention of various diseases, including tumors, inflammatory diseases, and cardiovascular diseases. Notably, owing to the particular molecular structure, polyphenols can combine with proteins, metal ions, polymers, and nucleic acids providing better strategies for polyphenol-delivery strategies. This contributes to the inherent advantages of polyphenols as important functional components for other drug delivery strategies, e.g., protecting nanodrugs from oxidation as a protective layer, improving the physicochemical properties of carbohydrate polymer carriers, or being used to synthesize innovative functional delivery vehicles. Polyphenols have emerged as a multifaceted player in novel drug delivery systems, both as therapeutic agents delivered to intervene in disease progression and as essential components of drug carriers. Although an increasing number of studies have focused on polyphenol-based nanodrug delivery including epigallocatechin-3-gallate, curcumin, resveratrol, tannic acid, and polyphenol-related innovative preparations, these molecules are not without inherent shortcomings. The active biochemical characteristics of polyphenols constitute a prerequisite to their high-frequency use in drug delivery systems and likewise to provoke new challenges for the design and development of novel polyphenol drug delivery systems of improved efficacies. In this review, we focus on both the targeted delivery of polyphenols and the application of polyphenols as components of drug delivery carriers, and comprehensively elaborate on the application of polyphenols in new types of drug delivery systems. According to the different roles played by polyphenols in innovative drug delivery strategies, potential limitations and risks are discussed in detail including the influences on the physical and chemical properties of nanodrug delivery systems, and their influence on normal physiological functions inside the organism.

Soft Materials that Intercept, Respond to, and Sequester Bacterial Siderophores

We report the design and characterization of Fe-containing soft materials that respond to, interface with, and/or sequester Fe-chelating 'siderophores' that bacteria use to scavenge for iron and regulate iron homeostasis. We demonstrate that metal-organic network coatings fabricated by crosslinking tannic acid with iron(III) are stable in bacterial growth media, but erode upon exposure to biologically relevant concentrations of enterobactin and deferoxamine B, two siderophores produced by Gram-negative and Gram-positive bacteria, respectively. Our results are consistent with changes in network stability triggered by the extraction of iron(III) and reveal rates of siderophore-induced disassembly to depend upon both siderophore concentration and affinity for iron(III). These coatings also disassemble when incubated in the presence of cultures of wild-type Escherichia coli. Assays using genetically modified strains of E. coli reveal the erosion of these materials by live cultures to be promoted by secretion of enterobactin and not from other factors resulting from bacterial growth and metabolism. This stimuli-responsive behavior can also be exploited to design coatings that release the Fe-chelating antibiotic ciprofloxacin into bacterial cultures. Finally, we report the discovery of Fe-containing polymer hydrogels that avidly sequester and scavenge enterobactin from surrounding media. The materials reported here are (i) capable of interfacing or interfering with mechanisms that bacteria use to maintain iron homeostasis, either by yielding iron to or by sequestering iron-scavenging agents from bacteria, and can (ii) respond dynamically to or report on the presence of populations of iron-scavenging bacteria. Our results thus provide new tools that could prove useful for microbiological research and enable new stimuli-responsive strategies for interfacing with or controlling the behaviors of communities of iron-scavenging bacteria.

Triple-Layered Metal-Organic Framework Hybrid for Tandem Response-Driven Enhanced Chemotherapy

The precise release of drugs is essential to improve cancer therapeutic efficacy. In this work, a tandem responsive strategy was developed based on a triple-layered metal-organic framework (MOF) hybrid. The MOF nanoprobe was stepwise fabricated with a telomerase-responsive inner, a pH-sensitive MOF filling and H₂ O₂ -responsive coordination complex shell of Fe³⁺ and eigallocatechin gallate (EGCG). In the tumor microenvironment, the shell was dissociated by endogenous H₂ O₂ and simultaneously produced highly reactive hydroxyl radicals by a Fenton reaction. Meanwhile, the released EGCG could downregulate the expression of P-glycoprotein responsible for drug resistance. After the dissociation of the framework by protons, telomerase could trigger the release of the drug from the DNA duplex on the exposed inner shell. By integrating confined drug release, inhibited efflux pump and chemodynamic therapy, the all-in-one chemotherapy strategy was identified with enhanced therapeutic efficacy in drug-resistant cancer cells.

Polyphenol-Containing Nanoparticles: Synthesis, Properties, and Therapeutic Delivery

Polyphenols, the phenolic hydroxyl group-containing organic molecules, are widely found in natural plants and have shown beneficial effects on human health. Recently, polyphenol-containing nanoparticles have attracted extensive research attention due to their antioxidation property, anticancer activity, and universal adherent affinity, and thus have shown great promise in the preparation, stabilization, and modification of multifunctional nanoassemblies for bioimaging, therapeutic delivery, and other biomedical applications. Additionally, the metal-polyphenol networks, formed by the coordination interactions between polyphenols and metal ions, have been used to prepare an important class of polyphenol-containing nanoparticles for surface modification, bioimaging, drug delivery, and disease treatments. By focusing on the interactions between polyphenols and different materials (e.g., metal ions, inorganic materials, polymers, proteins, and nucleic acids), a comprehensive review on the synthesis and properties of the polyphenol-containing nanoparticles is provided. Moreover, the remarkable versatility of polyphenol-containing nanoparticles in different biomedical applications, including biodetection, multimodal bioimaging, protein and gene delivery, bone repair, antibiosis, and cancer theranostics is also demonstrated. Finally, the challenges faced by future research regarding the polyphenol-containing nanoparticles are discussed.

Metal-phenolic networks for cancer theranostics

Metal-phenolic networks (MPNs) have shown promising potential in biomedical applications since they provide a rapid, simple and robust way to construct multifunctional nanoplatforms. As a novel nanomaterial self-assembled from metal ions and polyphenols, MPNs can be prepared to assist the theranostics of cancer owing to their bio-adhesiveness, good biocompatibility, versatile drug loading, and stimuli-responsive profile. This Critical Review aims to summarize recent progress in MPN-based nanoplatforms for multimodal tumor therapy and imaging. First, the advantages of MPNs as drug carriers are summarized. Then, various tumor therapeutic modalities based on MPNs are introduced. Next, MPN-based theranostic systems are reviewed. In terms of in vivo applications, specific attention is paid to their biosafety, biodistribution, as well as excretion. Finally, some problems and limitations of MPNs are discussed, along with a future perspective on the field.

Stem cell spheroid engineering with osteoinductive and ROS scavenging nanofibers for bone regeneration

Stem cell spheroids have been widely investigated to accelerate bone tissue regeneartion. However, the directed differentiation of stem cells into osteoblastic lineage and the prevention of cells from damage by reactive oxygen species (ROS) remain challenge. Here, we developed osteoinductive and ROS scavenging extracellular matrix (ECM)-mimicking synthetic fibers based on epigallocatechin gallate (EGCG) coating. They were then utilized to fabricate engineered spheroids with human adipose-derived stem cells (hADSCs) for bone tissue regeneation. The EGCG-mineral fibers (EMF) effectively conferred osteoinductive and ROS scavenging signals on the hADSCs within spheroids, demonstrating relative upregulation of antioxidant genes (SOD-1 (25.8±2.1) and GPX-1 (3.3±0.1) and greater level of expression of osteogenic markers, RUNX2 (5.8±0.1) and OPN (5.9±0.1), compared to hADSCs in the spheroids without EMF. The in vitro overexpression of osteogenic genes from hADSCs was achieved from absence of osteogenic supplenments. Furthermore, in vivo transplantation of hADSCs spheroids with the EMF significantly promoted calvarial bone regeneration (48.39±9.24%) compared to that from defect only (17.38±6.63%), suggesting that the stem cell spheroid biofabrication system with our novel mineralization method described here is a promising tool for bone tissue regeneration.

Polyphenol-cisplatin complexation forming core-shell nanoparticles with improved tumor accumulation and dual-responsive drug release for enhanced cancer chemotherapy

Cisplatin (CDDP) is a potent first-line antitumor drug but suffers severe side effects and poor pharmacokinetics. Its complexation with polycarboxylic acids, such as polyglutamic acids, is generally used to fabricate nanoformulations for CDDP delivery; however, the multiple strong complexations makes intracellular drug release slow. Herein, we report a novel polyphenol-metal coordination method to fabricate CDDP-incorporated core-shell nanoparticles, which are stable in blood circulation but dissociate in the tumor. Methoxyl-PEG terminated with one or two gallic acids (PEG-GA or PEG-GA2) complexed CDDP and produced well-defined nanoparticles (PEG-GAx/Pt) with CDDP loading contents as high as 17.7% to 29.8%. The PEG-GAx/Pt nanoparticles were very stable in the physiological conditions and had slow blood clearance and efficient tumor accumulation, but dissociated quickly and released CDDP in response to the tumor acidity or elevated levels of reactive oxygen species (ROS). PEG-GAx/Pt nanoparticles exhibited improved antitumor efficiency against 4 T1 breast cancer and A549 lung carcinoma with much-reduced toxicity compared to free CDDP. The work demonstrates a new strategy of cisplatin-polyphenol coordination for developing platinum drugs' nanomedicines.

ROS-responsive capsules engineered from EGCG-Zinc networks improve therapeutic angiogenesis in mouse limb ischemia

The successful treatment of limb ischemia requires that promote angiogenesis along with microenvironment improvement. Zinc ions have been reported to stimulate angiogenesis, but application was limited to the toxicity concerns. We hypothesized that zinc based metal-EGCG capsule (EGCG/Zn Ps) can achieve sustained release Zn²⁺ resulting in reduced toxicity and improve angiogenesis as well as the improvement of microenvironment by ROS scavenging of EGCG. The surface morphology, zeta potential, infrared absorbance peaks and zinc ion release profile of the EGCG/Zn Ps were measured. In vitro, EGCG/Zn showed significantly antioxidant, anti-inflammatory and induced cell migration effect. In addition, EGCG/Zn Ps enabled the sustained release of zinc ions, which reduced cytotoxicity and enhanced the secretion of vascular endothelial growth factor (VEGF) in vitro and in vivo. In mouse models of limb ischemia, EGCG/Zn Ps promoted angiogenesis and cell proliferation in ischemic tissues. Moreover, EGCG/Zn Ps group exhibited the most significant recovery of limb ischemic score, limb temperature and blood flow than other groups. In conclusion, EGCG/Zn Ps is a safe and promising approach to combine the merit of Zn²⁺ and EGCG, thus enabling the direct application to limb ischemia.

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Metal-polyphenol networks have been firstly applied in the Limb ischemic disease.

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EGCG improve the microenvironment of ischemic whereas Zinc exerts angiogenic property.

•The slowly release of zinc ions were achieved, resulting in better biocompatibility.

The Progress and Prospect of Zeolitic Imidazolate Frameworks in Cancer Therapy, Antibacterial Activity, and Biomineralization

The progressive development of zeolitic imidazolate frameworks (ZIFs), as a subfamily of metal-organic frameworks (MOFs), and their unique features, including tunable pore size, large surface area, high thermal stability, and biodegradability/biocompatibility, have made them attractive in the field of biomedicine, especially for drug delivery and biomineralization applications. The high porosity of ZIFs gives them the opportunity for encapsulating a high amount of therapeutic drugs, proteins, imaging cargos, or a combination of them to construct advanced multifunctional drug delivery systems (DDSs) with combined therapeutic and imaging capabilities. This review summarizes recent strategies on the design and fabrication of ZIF-based nansystems and their exploration in the biomedical field. First, recent developments for the adjustment of particle size, functionality, and morphology of ZIFs are discussed, which are important for achieving optimized therapeutic/theranostic nanosystems. Second, recent trends on the application of ZIF nanocarriers for the loading of diverse cargos, including anticancer medicines, antibiotic drugs, enzymes, proteins, photosensitizers, as well as imaging and photothermal agents, are investigated in order to understand how multifunctional DDSs can be designed based on the ZIF nanoparticles to treat different diseases, such as cancer and infection. Finally, prospects on the future research direction and applications of ZIF-based nanomedicines are discussed.

Synthesis and modification of ZIF-8 and its application in drug delivery and tumor therapy

Metal–organic frameworks have the properties of high porosity, variable pore sizes, and easy modification as drug delivery systems. In particular, ZIF-8 based on Zn²⁺ has been extensively studied in the medical field due to its low toxicity and good biocompatibility. This review introduces the preparation and functional modification of ZIF-8, and its application in drug delivery, focusing on the single-stimulus and multi-stimulus response release of drugs in ZIF-8 materials, the integrated role of diagnosis and treatment with ZIF-8 in cancer treatment, and its application in the synergistic therapy of multiple cancer treatment methods. We summarize the latest developments of ZIF-8 in the field of drug delivery and tumor therapy, and present the main challenges that remain to be resolved in the ZIF-8 drug delivery system.

Synthesis and modification of ZIF-8 and its application in drug delivery, stimulus response-controlled drug release and tumor therapy.

Recent advancement of imidazolate framework (ZIF-8) based nanoformulations for synergistic tumor therapy

As a new kind of porous material, zeolitic imidazolate frameworks (ZIF-8) are built from zinc ions and 2-methylimidazolate and possess unique merits including high porosity, good structural regularity and tunability, adjustable surface functionality and intrinsic pH induced biodegradability. These advantages endow ZIF-8 with multiple functionalities and stimuli-responsive controlled release of loaded payloads by endogenous or exogenous means. In this review, we will summarize the recent advancement of ZIF-8 as nanocarriers for the loading of various molecules including chemotherapeutic drugs, photosensitizers, photothermal agents, and proteins to fabricate multifunctional nanocomposites for synergistic cancer therapy. In addition, the challenges and future developments in this area will be highlighted.

Enhancement of Antioxidant Activity in O/W Emulsion and Cholesterol-Reducing Capacity of Epigallocatechin by Derivatization with Representative Phytosterols

In this study, derivatization of epigallocatechin (EGC) by representative phytosterols (stigmasterol and β-sitosterol) was performed employing Steglich esterification. The structural identity and purity of epigallocatechin β-sitosterol (ESi) and epigallocatechin stigmasterol (ESt) were confirmed by NMR, FT-IR, and HPLC-MS. Further evaluation of ESi and ESt revealed their extraordinary antioxidant activities in O/W emulsion. Two different radical sources in oil or aqueous phase were applied to explore the antioxidant behavior in O/W emulsion. The mechanism was further investigated by fluorescent microscopy and transmission electron microscopy (TEM). Furthermore, incorporation of EGC with stigmasterol and β-sitosterol notably enhanced the cholesterol-reducing activity. TEM studies suggested the hydrogen bonding of EGC strengthened the aggregation network of ESi and ESt in the bile salt micelle. The exceptional properties of ESi and ESt signified their intriguing utilization in the food industry.

Polyphenol and self-assembly: metal polyphenol nanonetwork for drug delivery and pharmaceutical applications

[Formula: see text]

DOX-assisted functionalization of green tea polyphenol nanoparticles for effective chemo-photothermal cancer therapy

Green tea polyphenol nanoparticles with chemotherapeutic and photothermal performance exhibited effective anti-tumor effects in vivo with intravenous injection.

Wetting transition in nanochannels for biomimetic free-blocking on-demand drug transport

Water wetting behavior in nanometer dimensions is of great importance to the signal transmission and substance transport of organisms, e.g., aquaporins on cell membranes. A biological channel can control the transport of water and ions by regulating channel wettability, which results from the transition between the intrinsic hydrophobic state and the stimulus-induced hydration state. Inspired by aquaporins in nature, herein, a biomimetic free-blocking on-demand delivery system is proposed, which is constructed by controlling the wettability of the inner surface of nanochannels of mesoporous silica nanoparticles (MSNs). Such a system is completely different from the traditional physically occluding pore controlled release system. It circumvents the use of other extra capping agents, thus overcoming the limitations of the traditional nano "gate" blockage system with inherent instability, poor plugging capability and low biocompatibility. Additionally, further applications in drug delivery have shown that this system can selectively release entrapped drugs in beta cells triggered by intracellular glucose in a controlled manner but not in normal cells. This hydrophobic gating drug delivery system with simple and effective performance provides a new opportunity for constructing a mass transport platform from the perspective of surface wettability.

Therapeutic Role of Green Tea Polyphenols in Improving Fertility: A Review

Sperm cells are highly sensitive to reactive oxygen species (ROS), which are produced during cellular oxidation. In normal cell biology, ROS levels increase with a decreasing antioxidant response, resulting in oxidative stress which threatens sperm biology. Oxidative stress has numerous effects, including increased apoptosis, reduced motion parameters, and reduced sperm integrity. In this regard, green tea polyphenols (GrTPs) have been reported to possess properties that may increase the quality of male and female gametes, mostly via the capability of catechins to reduce ROS production. GrTPs have antioxidant properties that improve major semen parameters, such as sperm concentration, motility, morphology, DNA damage, fertility rate, and gamete quality. These unique properties of green tea catechins could improve reproductive health and represent an important study area. This exploratory review discusses the therapeutic effects of GrTPs against infertility, their possible mechanisms of action, and recommended supportive therapy for improving fertility in humans and in animals.