Designing supramolecular self-assembly nanomaterials as stimuli-responsive drug delivery platforms for cancer therapy

Multiscale metal-based nanocomposites for bone and joint disease therapies

Bone and joint diseases are debilitating conditions that can result in significant functional impairment or even permanent disability. Multiscale metal-based nanocomposites, which integrate hierarchical structures ranging from the nanoscale to the macroscale, have emerged as a promising solution to this challenge. These materials combine the unique properties of metal-based nanoparticles (MNPs), such as enzyme-like activities, stimuli responsiveness, and photothermal conversion, with advanced manufacturing techniques, such as 3D printing and biohybrid systems. The integration of MNPs within polymer or ceramic matrices offers a degree of control over the mechanical strength, antimicrobial efficacy, and the manner of drug delivery, whilst concomitantly promoting the processes of osteogenesis and chondrogenesis. This review highlights breakthroughs in stimulus-responsive MNPs (e.g., photo-, magnetically-, or pH-activated systems) for on-demand therapy and their integration with biocomposite hybrids containing cells or extracellular vesicles to mimic the native tissue microenvironment. The applications of these composites are extensive, ranging from bone defects, infections, tumors, to degenerative joint diseases. The review emphasizes the enhanced load-bearing capacity, bioactivity, and tissue integration that can be achieved through hierarchical designs. Notwithstanding the potential of these applications, significant barriers to progress persist, including challenges related to long-term biocompatibility, regulatory hurdles, and scalable manufacturing. Finally, we propose future directions, including machine learning-guided design and patient-specific biomanufacturing to accelerate clinical translation. Multiscale metal-based nanocomposites, which bridge nanoscale innovations with macroscale functionality, are a revolutionary force in the field of biomedical engineering, providing personalized regenerative solutions for bone and joint diseases.

In situ protein corona-camouflaged supramolecular assemblies remodel thrombotic microenvironment for improved arterial homeostasis

Arterial thrombosis is commonly accompanied by poor recanalization and high recurrence, typically caused by a fibrinolysis-resistant microenvironment. We identify elevated levels of plasminogen activator inhibitor-1 (PAI-1) and, notably, its strong correlation with inflammation in arterial thrombosis. To address this, small molecular inhibitors of PAI-1 and inflammation are used as bioregulators to restore vascular homeostasis. We design a carrier-free supramolecular system based on the bioregulators-tuned self-assembly of a near-infrared thrombus probe, which preferentially forms protein corona in situ to enhance plasma stability. Under acidic conditions and increased shear stress, the supramolecular assemblies disintegrate, enabling site-specific cargo release. In vivo, the probe accumulates 22.8-fold more in the thrombotic than contralateral artery. Functionally, this nanomedicine improves outcomes in mice with carotid artery thrombosis and chronic cerebral ischemia. Mechanistically, it down-regulates NF-κB signaling, inhibits NETosis and glycolysis, and up-regulates cGMP-mediated signaling, thereby alleviating inflammation and promoting fibrinolysis. This study offers an innovative codelivery strategy using supramolecular assemblies to advance therapies for arterial thrombosis.

Nanoscale Spatial Control over the Self-Assembly of Small Molecule Hydrogelators

Spatial control over molecular self-assembly at the nano scale offers great potential for many high-tech applications, yet remains a challenging task. Here, we report a polymer brush-mediated strategy to confine the self-assembly of hydrazone-based hydrogelators exclusively at nanoparticle surfaces. The surfaces of these nanoparticles are grafted with negatively charged polyacrylic acid, which enrich protons that can catalyze the in situ formation and self-assembly of hydrazone-based gelators. We found that, with respect to the polymer lengths, the concentration of the nanoparticles presents more significant effects on the self-assembly process and the properties of the resultant hydrogels, including gelation time, stiffness, and network morphology. More interestingly, the hydrogel fibers are found to be formed specifically around the nanoparticles, demonstrating the directed nanoscale molecular self-assembly. This work demonstrates that triggering molecular self-assembly using catalysis can serve as an effective way to realize directed molecular self-assembly at the nano scale, which may serve as a powerful approach to improve many material properties, such as the mechanical properties of supramolecular materials as we found in this work.

How Advanced are Self-Assembled Nanomaterials for Targeted Drug Delivery? A Comprehensive Review of the Literature

The development of effective drug delivery systems is a key focus in pharmaceutical research, aiming to enhance therapeutic efficacy while minimizing adverse effects. Self-assembled nanostructures present a promising solution due to their tunable properties, biocompatibility, and ability to encapsulate and deliver therapeutic agents to specific targets. This review examines recent advancements in drug-based self-assembled nanostructures for targeted delivery applications, including drug-drug conjugates, polymeric-based architectures, biomolecules, peptides, DNA, squalene conjugates and amphiphilic drugs. Various strategies for fabricating these nanostructures are discussed, with an emphasis on the design principles and mechanisms underlying their self-assembly and potential for targeted drug delivery to specific tissues or cells. Furthermore, the integration of targeting ligands, stimuli-responsive moieties and imaging agents into these nanostructures is explored for enhanced therapeutic outcomes and real-time monitoring. Challenges such as stability, scalability and regulatory hurdles in translating these nanostructures from bench to bedside are also addressed. Drug-based self-assembled nanostructures represent a promising platform for developing next-generation targeted drug delivery systems with improved therapeutic efficacy and reduced side effects.

Ferritin-Based Supramolecular Assembly Drug Delivery System for Aminated Fullerene Derivatives to Enhance Tumor-Targeted Therapy

Owing to their attractive antitumor effects, aminated fullerene derivatives are emerging as promising therapeutic drugs for cancer. However, their in vivo applications are severely limited due to cation toxicity. To address this problem, human heavy chain ferritin (HFn), possessing natural biocompatibility is utilized, to develop a novel supramolecular assembly drug delivery system. Specifically, tetra[4-(amino)piperidin-1-yl]-C60 (TAPC) is selected as the representative aminated fullerene, and a layer-by-layer assembly strategy is designed to controllably assemble TAPC with the negatively charged HFn into a hierarchical coassembly (H@T@H) via electrostatic interactions and hydrogen bonds. In this ordered multilayer structure, the surface displayed HFn endows the inner TAPC with biocompatibility, tumor-targeting and blood-brain barrier crossing ability. Additionally, the electrostatic assembly mode enables the acid-responsive disassembly of H@T@H to release TAPC in lysosomes. In the orthotopic glioma mouse model, the HFn-assembled TAPC (H@T@H) shows higher brain accumulation and a stronger inhibitory effect on glioma than polyethylene glycol (PEG)-coated TAPC. Moreover, in an experimental metastasis mouse model, H@T@H have significant preventive and therapeutic effects on tumor metastasis. Encouragingly, the ferritin-based supramolecular assembly strategy has been proven to have broad applicability for various aminated fullerene derivatives, showing promising potential for tackling the in vivo delivery challenges of cationic drugs.

Bicontinuous Nanoparticles from Spontaneous Self-Assembly of Block Copolymer Prodrug in Aqueous Medium for Potential Cancer Therapy

Despite having several advantages, bicontinuously structured polymeric nanoparticles (BSPNPs) are far less explored in the field of controlled drug delivery owing to the requirement of complex precursor copolymers and the associated multistep synthetic procedures. In this work, we report the synthesis of a redox-sensitive diblock copolymer (P1), which was subsequently utilized to prepare doxorubicin (DOX) containing a pH-labile prodrug (P2). P1 and P2 spontaneously self-assembled in aqueous media above their critical aggregation concentration, forming micellar nanoparticles with rare bicontinuous morphology that promotes loading of both hydrophobic and hydrophilic cargoes in different compartments. To the best of our knowledge, the formation of BSPNPs through direct self-assembly in aqueous media has not yet been reported. In vitro cellular studies asserted the higher safety profile of the nanoparticles against noncancerous cells (HEK293T) than free DOX, whereas they displayed higher drug-induced cytotoxicity against cancer cells (MCF-7) in comparison to free DOX, establishing them as promising cancer drug delivery systems.

Colorimetric Polydiacetylene Nanotubes from Self-Assembly of a Barbituric Acid-Derived Diacetylene

Covalent organic nanotubes offer enhanced stability, robustness, and functionality, compared to their noncovalent counterparts. This study explores constructing polydiacetylene (PDA) nanotubes using a two-step process: self-assembly via noncovalent interactions followed by UV-induced polymerization of a diacetylene template. A promising building block PCDA-BA consisting of a hydrogen-bonding headgroup, barbituric acid, linked to a linear diacetylene chain was prepared. Through self-complementary hydrogen bonding arising from barbituric acid and π-π stacking of diacetylene template directs molecular ordering to form a tapelike molecular arrangement, which then transforms to bilayer lamellar sheets that scroll into nanotubes with increasing solvent polarity. Fourier transform infrared spectroscopy and powder X-ray diffraction patterns show both single-wall and multiple-wall nanotubes, depending on the scrolling pathway. These noncovalent structures convert into covalently linked blue-phase chromogenic nanotubes (P(PCDA-BA)) via UV-induced polymerization. The blue phase P(PCDA-BA) shows promising potential as a colorimetric sensor material with significant reversible thermoreversibility up to 160 °C for multiple thermal cycles and hydrazine sensing capabilities. This study highlights the significance of molecular integration design in constructing covalent nanotubes with chromogenic properties.

Intelligent Drug Delivery: Pioneering Stimuli-Responsive Systems to Revolutionize Disease Management- An In-depth Exploration

In recent years, there has been an escalating interest in stimuli-responsive drug delivery systems (SRDDS) due to their ability to revolutionize the delivery of therapeutics. SRDDSs offer a multitude of benefits in comparison to conventional drug delivery systems (DDS), including spatiotemporal control of drug release, targeted delivery, and improved therapeutic efficacy. The development of various classes of stimuli-responsive DDS, such as pH-responsive, temperature-responsive, photo-responsive, redox responsive systems, has been propelled by advances in materials science, nanotechnology, and biotechnology. These systems exploit specific environmental or physiological cues to trigger drug release in a precisely controlled manner, making them highly promising for the treatment of various diseases. In this review article, an in-depth exploration of the principles, mechanisms, and applications of SRDDS in the context of diverse pathologies such as cancer, arthritis, Alzheimer's disease, atherosclerosis and tissue engineering has been provided. Furthermore, this article delves into the discussion of recent patents, market overview and the progress of research in clinical trials. Overall, this article underscores the transformative potential of SRDDS in enabling personalized, precise, and effective drug delivery for the treatment of the above-mentioned diseases.

First Vesicular Self-Assembly of an Apocarotenoid Bixin in Aqueous Liquids and Its Antibacterial Activity

Bixin 1 is the major constituent of the reddish carotenoids present in the seed-coat of Bixa orellana. The use of the extract of the seed-coat of Bixa orellana in food, cosmetics and garments is well known. The nano-sized long 24 C chain molecule has nine conjugated double bonds having extended conjugation with the '-COOH' and '-COOMe' groups present at the two ends of the molecule. Herein, we report the first self-assembly of bixin in several aqueous liquids. The molecule undergoes spontaneous self-assembly in several liquids yielding vesicular self-assembly. Characterizations of the self-assemblies of bixin were carried out by various microscopic techniques, X-ray diffraction and FTIR studies. The critical vesicular concentrations (CVCs) of the compound carried out in DMSO-water in three different solvent ratios as 2: 1 (v/v), 1: 1 (v/v) and 1: 4 (v/v) were determined to be 100 μM, 90 μM and 60 μM respectively indicating lower CVC values at higher proportion of water. Utilization of the vesicular self-assemblies of bixin have been demonstrated in the entrapment and release of fluorophores including the anticancer drugs doxorubicin and curcumin. Self-assembled bixin and curcumin loaded self-assembled bixin showed significant antibacterial activity with both Gram positive as well as Gram negative bacteria.

Metal-organic frameworks as nanoplatforms for combination therapy in cancer treatment

The integration of nanotechnology into cancer treatment has revolutionized chemotherapy, boosted its effectiveness while reduced side effects. Among the various nanotherapeutic approaches, metal-organic frameworks (MOFs) stand out as promising carriers for targeted chemotherapy, with the added benefit of enabling combination therapies. MOFs, composed of metal ions or clusters linked by coordination bonds, tackle critical issues in traditional cancer treatments, such as poor stability, limited efficacy, and severe side effects. Their key advantages include customizable size and shape, diverse compositions, controlled porosity, large surface areas, ease of modification, and biocompatibility. This review highlights recent advancements in the use of MOFs for cancer therapy, showcasing their role in both monotherapies and combination strategies. Additionally, it explores the future potential and challenges of MOF-based platforms in tumor treatment.

Assembling a new generation of radiopharmaceuticals with supramolecular theranostics

Supramolecular chemistry has been used to tackle some of the major challenges in modern science, including cancer therapy and diagnosis. Supramolecular platforms provide synthetic flexibility, rapid generation through self-assembly, facile labelling, unique topologies, tunable reversibility of the enabling noncovalent interactions, and opportunities for host-guest chemistry and mechanical bonding. In this Review, we summarize recent advances in the design and radiopharmaceutical application of discrete self-assembled coordination complexes and mechanically interlocked molecules - namely, metallacages and rotaxanes, respectively - as well as in situ-forming supramolecular aggregates, specifically pinpointing their potential as next-generation radiotheranostic agents. The outlook of such supramolecular constructs for potential applications in the clinic is discussed.

Recent advance for animal-derived polysaccharides in nanomaterials

Inspired by the structure characteristics of natural products, the size and morphology of particles are carefully controlled using a bottom-up approach to construct nanomaterials with specific spatial unit distribution. Animal polysaccharide nanomaterials, such as chitosan and chondroitin sulfate nanomaterials, exhibit excellent biocompatibility, degradability, customizable surface properties, and novel physical and chemical properties. These nanomaterials hold great potential for development in achieving a sustainable bio-economy. This paper provides a summary of the latest research results on the preparation of nanomaterials from animal polysaccharides. The mechanism for preparing nanomaterials through the bottom-up method from different sources of animal polysaccharides is introduced. Furthermore, this paper discusses the potential hazards posed by industrial applications to the environment and human health, as well as the challenges and future prospects associated with using animal polysaccharides in nanomaterials.

Hyaluronic Acid in Nanopharmaceuticals: An Overview

Hyaluronic acid (HA) is a naturally occurring, long, unbranched polysaccharide that plays a critical role in maintaining skin structure and hydration. Its unique properties make it a valuable component in the field of nanopharmaceuticals. The combination of HA into nanopharmaceuticals enhances its ability to interact with various therapeutic agents, improving the delivery and efficacy of drugs. HA-based nanoparticles, including solid lipid nanoparticles, and polymeric nanogels, offer controlled release, enhanced stability, and targeted delivery of therapeutic agents. These innovations significantly improve therapeutic outcomes and reduce side effects, making HA an essential tool in modern medicine. In general, HA-modified liposomes enhance drug encapsulation and targeting, while HA-modified solid lipid nanoparticles (SLNs) provide a solid lipid core for drug encapsulation, offering controlled release and stability. This article provides an overview of the potential applications and recent advancements of HA in nanopharmaceuticals, emphasizing its significant impact on the evolving field of targeted drug delivery and advanced therapeutic strategies. By delving into the unique properties of HA and its compatibility with various therapeutic agents, this review underscores the promising potential of HA in revolutionizing nanopharmaceuticals.

Development of Polymethine Dyes for NIR-II Fluorescence Imaging and Therapy

Fluorescence imaging in the second near-infrared window (NIR-II) is burgeoning because of its higher imaging fidelity in monitoring physiological and pathological processes than clinical visible/the second near-infrared window fluorescence imaging. Notably, the imaging fidelity is heavily dependent on fluorescence agents. So far, indocyanine green, one of the polymethine dyes, with good biocompatibility and renal clearance is the only dye approved by the Food and Drug Administration, but it shows relatively low NIR-II brightness. Importantly, tremendous efforts are devoted to synthesizing polymethine dyes for imaging preclinically and clinically. They have shown feasibility in the customization of structure and properties to fulfill various needs in imaging and therapy. Herein, a timely update on NIR-II polymethine dyes, with a special focus on molecular design strategies for fluorescent, photoacoustic, and multimodal imaging, is offered. Furthermore, the progress of polymethine dyes in sensing pathological biomarkers and even reporting drug release is illustrated. Moreover, the NIR-II fluorescence imaging-guided therapies with polymethine dyes are summarized regarding chemo-, photothermal, photodynamic, and multimodal approaches. In addition, artificial intelligence is pointed out for its potential to expedite dye development. This comprehensive review will inspire interest among a wide audience and offer a handbook for people with an interest in NIR-II polymethine dyes.

Integrated oral microgel system ameliorates renal fibrosis by hitchhiking co-delivery and targeted gut flora modulation

BACKGROUND

Renal fibrosis is a progressive process associated with chronic kidney disease (CKD), contributing to impaired kidney function. Active constituents in traditional Chinese herbs, such as emodin (EMO) and asiatic acid (AA), exhibit potent anti-fibrotic properties. However, the oral administration of EMO and AA results in low bioavailability and limited kidney accumulation. Additionally, while oral probiotics have been accepted for CKD treatment through gut microbiota modulation, a significant challenge lies in ensuring their viability upon administration. Therefore, our study aims to address both renal fibrosis and gut microbiota imbalance through innovative co-delivery strategies.

RESULTS

In this study, we developed yeast cell wall particles (YCWPs) encapsulating EMO and AA self-assembled nanoparticles (NPYs) and embedded them, along with Lactobacillus casei Zhang, in chitosan/sodium alginate (CS/SA) microgels. The developed microgels showed significant controlled release properties for the loaded NPYs and prolonged the retention time of Lactobacillus casei Zhang (L. casei Zhang) in the intestine. Furthermore, in vivo biodistribution showed that the microgel-carried NPYs significantly accumulated in the obstructed kidneys of rats, thereby substantially increasing the accumulation of EMO and AA in the impaired kidneys. More importantly, through hitchhiking delivery based on yeast cell wall and positive modulation of gut microbiota, our microgels with this synergistic strategy of therapeutic and modulatory interactions could regulate the TGF-β/Smad signaling pathway and thus effectively ameliorate renal fibrosis in unilateral ureteral obstruction (UUO) rats.

CONCLUSION

In conclusion, our work provides a new strategy for the treatment of renal fibrosis based on hitchhiking co-delivery of nanodrugs and probiotics to achieve synergistic effects of disease treatment and targeted gut flora modulation.

Hydrophobicity: The door to drug delivery

The engineering of intracellular delivery systems with the goal of achieving personalized medicine has been encouraged by advances in nanomaterial science as well as a greater understanding of diseases and of the biochemical pathways implicated in many disorders. The development of vectors able to transport the drug to a target location and release it only on demand is undoubtedly the primary issue. From a molecular perspective, the topography of drug carrier surfaces is directly related to the design of an effective drug carrier because it provides a physical hint to modifying its interactions with biological systems. For instance, the initial ratio of hydrophilic to hydrophobic surfaces and the changes brought about by external factors enable the release or encapsulation of a therapeutic molecule and the ability of the nanosystem to cross biological barriers and reach its target without causing systemic toxicity. The first step in creating new materials with enhanced functionality is to comprehend and characterize the interplay between hydrophilic and hydrophobic molecules at the molecular level. Therefore, the focus of this review is on the function of hydrophobicity, which is essential for matching the complexity of biological environments with the intended functionality.

Drug-initiated poly(thiocitc acid) polymer incorporating host-guest interaction for cancer combination chemotherapy

Combination chemotherapy has shown considerable promise for cancer therapy. However, the hydrophobicity of chemotherapeutic agents and the difficulties of precise drug co-administration severely hinder the development of combination chemotherapy. Herein, we develop a polymeric drug delivery system (D-PTA-CD) to provide robust loading capacity, glutathione-responsive drug release, and precise combination therapy. The vehicle is prepared based on poly(thioctic acid) (PTA) polymers using DM1, a chemotherapeutic agent, as the initiator to endow the vehicle with cancer-inhibiting activity. β-cyclodextrins are incorporated into the side chains to enhance drug loading capacity via host-guest interactions. Attributing to the sufficient disulfide bond on the backbone, D-PTA-CD exhibits accelerated drug release triggered by elevated glutathione levels. Doxorubicin (DOX) and camptothecin (CPT) are encapsulated by D-PTA-CD to afford the combination chemotherapy nanoparticles (NP), DOX-NP, and CPT-NP, respectively, which exhibit significant synergetic anti-cancer effects, highlighting the enormous potential of D-PTA-CD as a versatile drug delivery platform for cancer combination chemotherapy.

Supramolecular Nanostructures for the Delivery of Peptides in Cancer Therapy

Supramolecular nanostructured based delivery systems are emerging as a meaningful approach in the treatment of cancer, offering controlled drug release and improved therapeutic efficacy. The self-assembled structures can be small molecules, polymers, peptides, or proteins, which can be used and functionalized to achieve tailored release and target specific cells, tissues, or organs. These structures can improve the solubility and stability of drugs having low aqueous solubility by encapsulating and protecting them from degradation. Alongside, peptides as natural biomolecules have gained increasing attention as potential candidates in cancer treatment because of their biocompatibility, low cytotoxicity, and high specificity toward tumor cells. The amino acid sequences in peptide molecules are tunable, efficiently controlling the morphology of peptide-based self-assembled nanosystems and offering flexibility to form supramolecular nanostructures (SNs). It is evident from the current literature that the supramolecular nanostructures based delivery of peptide for cancer treatment hold great promise for future cancer therapy, offering potential strategies for personalized medicine with improved patient outcomes. SIGNIFICANCE STATEMENT: This review focuses on fundamentals and various drug delivery mechanisms based on SNs. Different SN approaches and recent literature reviews on peptide delivery are also presented to the readers.