Stimuli-responsive multifunctional glyconanoparticle platforms for targeted drug delivery and cancer cell imaging

Glycosylated AIE-active Red Light-triggered Photocage with Precisely Tumor Targeting Capability for Synergistic Type I Photodynamic Therapy and CPT Chemotherapy

Photocaging is an emerging protocol for precisely manipulating spatial and temporal behaviors over biological activity. However, the red/near-infrared light-triggered photolysis process of current photocage is largely singlet oxygen (1O2)-dependent and lack of compatibility with other reactive oxygen species (ROS)-activated techniques, which has proven to be the major bottleneck in achieving efficient and precise treatment. Herein, we reported a lactosylated photocage BT-LRC by covalently incorporating camptothecin (CPT) into hybrid BODIPY-TPE fluorophore via the superoxide anion radical (O2 -⋅)-cleavable thioketal bond for type I photodynamic therapy (PDT) and anticancer drug release. Amphiphilic BT-LRC could be self-assembled into aggregation-induced emission (AIE)-active nanoparticles (BT-LRCs) owing to the regulation of carbohydrate-carbohydrate interactions (CCIs) among neighboring lactose units in the nanoaggregates. BT-LRCs could simultaneously generate abundant O2 -⋅ through the aggregation modulated by lactose interactions, and DNA-damaging agent CPT was subsequently and effectively released. Notably, the type I PDT and CPT chemotherapy collaboratively amplified the therapeutic efficacy in HepG2 cells and tumor-bearing mice. Furthermore, the inherent AIE property of BT-LRCs endowed the photocaged prodrug with superior bioimaging capability, which provided a powerful tool for real-time tracking and finely tuning the PDT and photoactivated drug release behavior in tumor therapy.

A DNA damage-amplifying nanoagent for cancer treatment via two-way regulation of redox dyshomeostasis and downregulation of tetrahydrofolate

DNA damage-based therapy is widely used in cancer treatment, yet its therapeutic efficacy is constrained by the redox homeostasis and DNA damage repair mechanisms of tumor cells. To address these limitations and enhance the efficacy of DNA damage-based therapy, HA-CuH@MTX, a copper-histidine metal-organic complex (CuH) loaded with methotrexate (MTX) and modified with hyaluronic acid (HA), was developed to amplify the DNA damage induced. In vitro experiments demonstrated that the presence of both Cu+ and Cu2+ in HA-CuH@MTX enables two-way regulated redox dyshomeostasis (RDH), achieved through Cu+-catalyzed generation of •OH and Cu2+-mediated consumption of glutathione, thereby facilitating efficient DNA oxidative damage. In addition, DNA damage repair is synergistically inhibited by impairing nucleotide synthesis via histidine metabolism and MTX downregulation of tetrahydrofolate, a crucial raw material in nucleotide synthesis. In vivo experiments with 4T1 tumor-bearing mice demonstrate 83.6 % inhibition of tumor growth by HA-CuH@MTX. This work provides a new strategy to amplify the DNA damage caused by DNA damage-based cancer therapies, and holds great potential for improving their therapeutic efficacy.

Fluorescent Self-Assembled Complexes Based on Glyco-Functionalized G-Quadruplexes as a Targeted Delivery Platform

Targeted delivery systems combined with the stimuli-responsive release of drug molecules hold noteworthy promise for precision medicine, enabling treatments with enhanced effectiveness and reduced adverse effects. An ideal drug delivery platform with versatile targeting moieties, the capability of combinational payloads, and simple preparation is highly desirable. Herein, we developed pH-sensitive fluorescent self-assembled complexes (SACs) of a galactose-functionalized G-quadruplex (G4) and a coumarin carboxamidine derivative as a targeted delivery platform through the nanoprecipitation method. These SACs selectively targeted hepatocellular carcinoma (HepG2) cells in fluorescence imaging after a short incubation and exerted specific anticancer effects in an appropriate dose range. Co-delivery of 1 μM prodrug floxuridine oligomers and 16 μg/mL SACs (minimal hemolytic effect) significantly reduced the cytotoxicity of the nucleoside anticancer drug on normal cells (NIH/3T3), kept up to 70% alive after 72-h incubation, and improved anticancer efficacy compared to SACs alone. This strategy can be extended to ratiometric multidrug delivery through self-assembly for targeted combinational therapy.

Cu0-based nanoparticles boost anti-tumor efficacy via synergy of cuproptosis and ferroptosis enhanced by cuproptosis-induced glutathione synthesis disorder

Apoptotic resistance of tumor often leads to poor efficacy from mono-therapy based on apoptosis. Cuproptosis, a new type of non-apoptotic cell death related to mitochondrial dysfunction, can alter metabolism and enhance ferroptosis, providing a promising strategy for effective synergistic cancer treatment. In this work, Cu0-based nanoparticles (denoted as HA-ZCu) were successfully developed to improve anti-tumor efficacy by combining cuproptosis with enhanced ferroptosis, which was achieved by cuproptosis-induced glutathione synthesis disorder. In vitro studies revealed that HA-ZCu effectively induced cuproptosis and ferroptosis in HepG2 cells. Moreover, HA-ZCu induced mitochondrial dysfunction and decreased intracellular adenosine triphosphate (ATP), glutamate, and glutathione, demonstrating the effective synergy. In vivo studies further approved the synergistic therapeutic efficacy of HA-ZCu, where the inhibition rate of tumor growth reached 83.2 %. This work represents the first example of enhanced anti-tumor efficacy via cuproptosis and ferroptosis synergy through cuproptosis-induced glutathione synthesis disorder.

Stimulus-Responsive Nano-Prodrug Strategies for Cancer Therapy: A Focus on Camptothecin Delivery

Camptothecin (CPT) is a highly cytotoxic molecule with excellent antitumor activity against various cancers. However, its clinical application is severely limited by poor water solubility, easy inactivation, and severe toxicity. Structural modifications and nanoformulations represent two crucial avenues for camptothecin's development. However, the potential for further structural modifications is limited, and camptothecin nanoparticles fabricated via physical loading have the drawbacks of low drug loading and leakage. Prodrug-based CPT nanoformulations have shown unique advantages, including increased drug loading, reduced burst release, improved bioavailability, and minimal toxic side effects. Stimulus-responsive CPT nano-prodrugs that respond to various endogenous or exogenous stimuli by introducing various activatable linkers to achieve spatiotemporally responsive drug release at the tumor site. This review comprehensively summarizes the latest research advances in stimulus-responsive CPT nano-prodrugs, including preparation strategies, responsive release mechanisms, and their applications in cancer therapy. Special focus is placed on the release mechanisms and characteristics of various stimulus-responsive CPT nano-prodrugs and their application in cancer treatment. Furthermore, clinical applications of CPT prodrugs are discussed. Finally, challenges and future research directions for CPT nano-prodrugs are discussed. This review to be valuable to readers engaged in prodrug research is expected.

A Paramagnetic Metal-Organic Framework Enhances Mild Magnetic Hyperthermia Therapy by Downregulating Heat Shock Proteins and Promoting Ferroptosis via Aggravation of Two-Way Regulated Redox Dyshomeostasis

Mild magnetic hyperthermia therapy (MMHT) holds great potential in treating deep-seated tumors, but its efficacy is impaired by the upregulation of heat shock proteins (HSPs) during the treatment process. Herein, Lac-FcMOF, a lactose derivative (Lac-NH2 ) modified paramagnetic metal-organic framework (FcMOF) with magnetic hyperthermia property and thermal stability, has been developed to enhance MMHT therapeutic efficacy. In vitro studies showed that Lac-FcMOF aggravates two-way regulated redox dyshomeostasis (RDH) via magnetothermal-accelerated ferricenium ions-mediated consumption of glutathione and ferrocene-catalyzed generation of ∙OH to induce oxidative damage and inhibit heat shock protein 70 (HSP70) synthesis, thus significantly enhancing the anti-cancer efficacy of MMHT. Aggravated RDH promotes glutathione peroxidase 4 inactivation and lipid peroxidation to promote ferroptosis, which further synergizes with MMHT. H22-tumor-bearing mice treated with Lac-FcMOF under alternating magnetic field (AMF) demonstrated a 90.4% inhibition of tumor growth. This work therefore provides a new strategy for the simple construction of a magnetic hyperthermia agent that enables efficient MMHT by downregulating HSPs and promoting ferroptosis through the aggravation of two-way regulated RDH.

NIR-Triggered Thermosensitive Nanoreactors for Dual-Guard Mechanism-Mediated Precise and Controllable Cancer Chemo-Phototherapy

Thermosensitive nanoparticles can be activated by externally applying heat, either through laser irradiation or magnetic fields, to trigger the release of drug payloads. This controlled release mechanism ensures that drugs are specifically released at the tumor site, maximizing their effectiveness while minimizing systemic toxicity and adverse effects. However, its efficacy is limited by the low concentration of drugs at action sites, which is caused by no specific target to tumor sties. Herein, hyaluronic acid (HA), a gooey, slippery substance with CD44-targeting ability, was conjugated with a thermosensitive polymer poly(acrylamide-co-acrylonitrile) to produce tumor-targeting and thermosensitive polymeric nanocarrier (HA-P) with an upper critical solution temperature (UCST) at 45 °C, which further coloaded chemo-drug doxorubicin (DOX) and photosensitizer Indocyanine green (ICG) to prepare thermosensitive nanoreactors HA-P/DOX&ICG. With photosensitizer ICG acting as the "temperature control element", HA-P/DOX&ICG nanoparticles can respond to temperature changes when receiving near-infrared irradiation and realize subsequent structure depolymerization for burst drug release when the ambient temperature was above 45 °C, achieving programmable and on-demand drug release for effective antitumor therapy. Tumor inhibition rate increased from 61.8 to 95.9% after laser irradiation. Furthermore, the prepared HA-P/DOX&ICG nanoparticles possess imaging properties, with ICG acting as a probe, enabling real-time monitoring of drug distribution and therapeutic response, facilitating precise treatment evaluation. These results provide enlightenment for the design of active tumor targeting and NIR-triggered programmable and on-demand drug release of thermosensitive nanoreactors for tumor therapy.

Synthesis, Cellular Uptake, and Photodynamic Activity of Oligogalactosyl Zinc(II) Phthalocyanines

A series of di-α-substituted zinc(II) phthalocyanines with different number of galactose moieties, ranging from 1 to 8, namely Pc-gal_n (n=1, 2, 4, and 8) were designed and synthesized. The synthesis involved the copper-catalyzed azide-alkyne cycloaddition reaction of a mono- or dialkynyl zinc(II) phthalocyanine with an acetyl-protected galactosyl azide or its dendritic derivative with four acetyl-protected galactosyl groups, followed by removal of the acetyl protecting groups via alkaline hydrolysis. In N,N-dimethylformamide, these oligogalactosyl phthalocyanines were non-aggregated as shown by the strong Q-band absorption and fluorescence emission. Owing to the di-α-substitution, they also behaved as efficient singlet oxygen generators upon light irradiation with a singlet oxygen quantum yield of 0.84. The spectroscopic and photophysical properties were not affected by the number of galactosyl units. In contrast, the compounds became significantly aggregated and quenched in phosphate-buffered saline. Their cellular uptake was then studied using a range of cell lines, which generally followed the order Pc-gal₁ >Pc-gal₂ ≈Pc-gal₄ >Pc-gal₈ . Interestingly, the di-galactosyl analogue exhibited selective uptake against HeLa human cervical carcinoma cells through an energy-dependent pathway instead of the expected asialoglycoprotein receptor. Upon light irradiation, it could effectively kill the cells with a half-maximal inhibitory concentration of 0.58 μM.

A tetrazine-responsive isonitrile-caged photosensitiser for site-specific photodynamic therapy

We report herein a versatile and efficient bioorthogonal strategy to actualise targeted delivery and site-specific activation of photosensitisers for precise antitumoural photodynamic therapy. The strategy involved the use of an isonitrile-caged distyryl boron dipyrromethene-based photosensitiser, labelled as NC-DSBDP, of which the photoactivities could be specifically activated upon conversion of the meso ester substituent to carboxylate initiated by the [4 + 1] cycloaddition with a tetrazine derivative. By using two tetrazines conjugated with a galactose moiety or the GE11 peptide, labelled as gal-Tz and GE11-Tz, we could selectively label the cancer cells overexpressed with the asialoglycoprotein receptor and the epidermal growth factor receptor respectively. Upon encountering the internalised NC-DSBDP, these tetrazines triggered the "ester-to-carboxylate" transformation of this compound, activating its fluorescence and reactive oxygen species generation inside the target cells. The bioorthogonal activation was also demonstrated in vivo, leading to effective photo-eradication of the tumour in nude mice.

Nanococktail Based on Supramolecular Glyco-Assembly for Eradicating Tumors In Vivo

The development of robust phototherapeutic strategies for eradicating tumors remains a significant challenge in the transfer of cancer phototherapy to clinical practice. Here, a phototherapeutic nanococktail atovaquone/17-dimethylaminoethylamino-17-demethoxygeldanamycin/glyco-BODIPY (ADB) was developed to enhance photodynamic therapy (PDT) and photothermal therapy (PTT) via alleviation of hypoxia and thermal resistance that was constructed using supramolecular self-assembly of glyco-BODIPY (BODIPY-SS-LAC, BSL-1), hypoxia reliever atovaquone (ATO), and heat shock protein inhibitor 17-dimethylaminoethylamino-17-demethoxygeldanamycin (17-DMAG). Benefiting from a glyco-targeting and glutathione (GSH) responsive units BSL-1, ADB can be rapidly taken up by hepatoma cells, furthermore the loaded ATO and 17-DMAG can be released in original form into the cytoplasm. Using in vitro and in vivo results, it was confirmed that ADB enhanced the synergetic PDT and PTT upon irradiation using 685 nm near-infrared light (NIR) under a hypoxic tumor microenvironment where ATO can reduce O₂ consumption and 17-DMAG can down-regulate HSP90. Moreover, ADB exhibited good biosafety, and tumor eradication in vivo. Hence, this as-developed phototherapeutic nanococktail overcomes the substantial obstacles encountered by phototherapy in tumor treatment and offers a promising approach for the eradication of tumors.

Glycoconjugate Nanoparticle-Based Systems in Cancer Immunotherapy: Novel Designs and Recent Updates

For many years, cell-surface glycans (in particular, Tumor-Associated Carbohydrate Antigens, TACAs) have been the target of both passive and active anticancer immunotherapeutic design. Recent advances in immunotherapy as a treatment for a variety of malignancies has revolutionized anti-tumor treatment regimens. Checkpoint inhibitors, Chimeric Antigen Receptor T-cells, Oncolytic virus therapy, monoclonal antibodies and vaccines have been developed and many approvals have led to remarkable outcomes in a subset of patients. However, many of these therapies are very selective for specific patient populations and hence the search for improved therapeutics and refinement of techniques for delivery are ongoing and fervent research areas. Most of these agents are directed at protein/peptide epitopes, but glycans-based targets are gaining in popularity, and a handful of approved immunotherapies owe their activity to oligosaccharide targets. In addition, nanotechnology and nanoparticle-derived systems can help improve the delivery of these agents to specific organs and cell types based on tumor-selective approaches. This review will first outline some of the historical beginnings of this research area and subsequently concentrate on the last 5 years of work. Based on the progress in therapeutic design, predictions can be made as to what the future holds for increasing the percentage of positive patient outcomes for optimized systems.

A GLUTs/GSH cascade targeting-responsive bioprobe for the detection of circulating tumor cells

A GLUTs/GSH cascade targeting-responsive bioprobe, GluCC, was rationally designed and synthesized for the first time via the coordination of copper ions with a glucose-modified coumarin derivative ligand (GluC). GluCC can specifically detect circulating tumor cells (CTCs) in lung metastatic mice models by targeting the Warburg effect and responding to overexpressed glutathione in the tumor microenvironment. This bioprobe with a simple detection procedure has significant advantages for CTC detection.

A brief insight to the role of glyconanotechnology in modern day diagnostics and therapeutics

Carbohydrate-protein and carbohydrate-carbohydrate interactions are very important for various biological processes. Although the magnitude of these interactions is low compared to that of protein-protein interaction, the magnitude can be boosted by multivalent approach known as glycocluster effect. Nanoparticle platform is one of the best ways to present diverse glycoforms in multivalent manner and thus, the field of glyconanotechnology has emerged as an important field of research considering their potential applications in diagnostics and therapeutics. Considerable advances in the field have been achieved through development of novel techniques, use of diverse metallic and non-metallic cores for better efficacy and application of ever-increasing number of carbohydrate ligands for site-specific interaction. The present review encompasses the recent developments in the area of glyconanotechnology and their future promise as diagnostic and therapeutic tools.

Cell surface-localized imaging and sensing

Systematically dissecting the molecular basis of the cell surface as well as its related biological activities is considered as one of the most cutting-edge fields in fundamental sciences. The advent of various advanced cell imaging techniques allows us to gain a glimpse of how the cell surface is structured and coordinated with other cellular components to respond to intracellular signals and environmental stimuli. Nowadays, cell surface-related studies have entered a new era featured by a redirected aim of not just understanding but artificially manipulating/remodeling the cell surface properties. To meet this goal, biologists and chemists are intensely engaged in developing more maneuverable cell surface labeling strategies by exploiting the cell's intrinsic biosynthetic machinery or direct chemical/physical binding methods for imaging, sensing, and biomedical applications. In this review, we summarize the recent advances that focus on the visualization of various cell surface structures/dynamics and accurate monitoring of the microenvironment of the cell surface. Future challenges and opportunities in these fields are discussed, and the importance of cell surface-based studies is highlighted.

Glycomacromolecules: Addressing challenges in drug delivery and therapeutic development

Carbohydrate-based materials offer exciting opportunities for drug delivery. They present readily available, biocompatible components for the construction of macromolecular systems which can be loaded with cargo, and can enable targeting of a payload to particular cell types through carbohydrate recognition events established in biological systems. These systems can additionally be engineered to respond to environmental stimuli, enabling triggered release of payload, to encompass multiple modes of therapeutic action, or to simultaneously fulfil a secondary function such as enabling imaging of target tissue. Here, we will explore the use of glycomacromolecules to deliver therapeutic benefits to address key health challenges, and suggest future directions for development of next-generation systems.

Antitumour properties based on the self-assembly of camptothecin and carbamoylmannose conjugates

Camptothecin (CPT) and its analogues show potent antitumour activity. However, poor water solubility and severe side effects have restricted their applications in clinical practice. In this paper, a novel self-assembly based on camptothecin and carbamoylmannose conjugates (CPT-Man) was constructed. The self-assembly increased the water solubility of camptothecin to 0.64 mg/ml and antitumour activity. Moreover, CPT-Man could induce obvious cancer cell apoptosis. This work provides a new approach for exploring carbohydrate-modified antitumour properties by self-assembled CPT drugs.

A facile PEG/thiol-functionalized nanographene oxide carrier with an appropriate glutathione-responsive switch

A novel nanographene oxide/PEG-based bioreduction-responsive smart drug delivery system with a GSH-responsive disulfide linker as the controlled release switch can selectively release anti-cancer drugs in cancer cells.

Collaborative assembly of doxorubicin and galactosyl diblock glycopolymers for targeted drug delivery of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) patients suffer from severe pain due to the serious systemic side effects and low efficiency of chemotherapeutic drugs, and it is important to develop novel drug delivery systems to circumvent these issues. In this study, a series of galactose-based glycopolymers, poly(N-(prop-2-enoyl)-β-d-galactopyranosylamine)-b-poly(N-isopropyl acrylamide) (pGal(OH)-b-pNIPAA), were prepared through a sequential reversible addition-fragmentation chain transfer (RAFT) polymerization and tetrabutylammonium hydroxide (TBAOH)-mediated removal of acetyl groups. Hydrophilic doxorubicin hydrochloride was introduced to undergo collaborative assembly with poly(N-(prop-2-enoyl)-β-d-peracetylated galactosamine)-b-poly(N-isopropyl acrylamide) (pGal(Ac)-b-pNIPAA) via TBAOH treatment. pGal-b-pNIPAA/doxorubicin (DOX) delivery nanoparticles (GND NPs) formed by collaborative assembly were fully characterized by NMR, TEM and FT-IR, indicating the well-controlled formation of particles with uniform size and high efficiency in terms of drug loading and encapsulation compared with conventional adsorption methods. Meanwhile, the GND NPs were observed to be rapidly disintegrated under acidic conditions and resulted in an increased release of DOX. Cellular experiments showed that pGal-b-pNIPAA/DOX is apparently an asialoglycoprotein receptor (ASGPR)-mediated target of HCC, resulting in enhanced cellular uptake to HepG2 cells and anti-tumor efficacy in vitro. Furthermore, GND NPs III exerted more sustainable and effective anti-tumor effects compared to free DOX on a transgenic zebrafish TO(Kras^G12V) model in vivo. These results indicated that the biocompatible nanomaterials developed by collaborative assembly with galactosyl diblock glycopolymers and DOX may serve as a promising candidates for targeting therapy of HCC.

Targeted photoswitchable imaging of intracellular glutathione by a photochromic glycosheet sensor

The development of photochromic fluorescence sensors with dynamic and multiple-signaling is beneficial to the improvement of biosensing/imaging precision. However, elaborate designs with complicated molecular structures are always required to integrate these functions into one molecule. By taking advantages of both redox-active/high loading features of two-dimensional (2D) manganese dioxide (MnO₂) and dynamic fluorescence photoswitching of photochromic sensors, we here design a hybrid photochromic MnO₂ glycosheet (Glyco-DTE@MnO₂) to achieve the photoswitchable imaging of intracellular glutathione (GSH). The photochromic glycosheet manifests significantly turn-on fluorescence and dynamic ON/OFF fluorescence signals in response to GSH, which makes it favorable for intracellular GSH double-check in targeted human hepatoma cell line (HepG2) through the recognition between β-D-galactoside and asialoglycoprotein receptor (ASGPr) on cell membranes. The dynamic fluorescence signals and excellent selectivity for detection and imaging of GSH ensure the precise determination of cell states, promoting its potential applications in future disease diagnosis and therapy.

Stable, Bioresponsive, and Macrophage-Evading Polyurethane Micelles Containing an Anionic Tripeptide Chain Extender

Polymeric nanocarriers have been extensively used in medicinal applications for drug delivery. However, intravenous nanocarriers circulating in the blood will be rapidly cleared from the mononuclear macrophage system. The surface physicochemical characterizations of nanocarriers are the primary factors to determine their fate in vivo, such as evading the reticuloendothelial system, exhibiting long blood circulation times, and accumulating in the targeted site. In this work, we develop a series of polyurethane micelles containing segments of an anionic tripeptide, hydrophilic mPEG, and disulfide bonds. It is found that the long hydrophilic mPEG can shield the micellar surface and have a synergistic effect with the negatively charged tripeptide to minimize macrophage phagocytosis. Meanwhile, the disulfide bond can rapidly respond to the intracellular reduction environment, leading to the acceleration of drug release and improvement of the therapeutic effect. Our results verify that these anionic polyurethane micelles hold great potential in the development of the stealth immune system and controllable intracellular drug transporters.

Glutathione responsive cubic gel particles cyclodextrin metal-organic frameworks for intracellular drug delivery

Novel cubic gel particles (ssCGP) with Glutathione (GSH) triggered drug release features were prepared by crosslinking the cyclodextrin based metal-organic frameworks (CD-MOFs) templets with a newly synthesized biodegradable disulfide bond-bearing linker and removing of the potassium ion in sequence. The morphology and size of ssCGP were investigated by field emission scanning electron microscope (FESEM) and dynamic light scattering. Energy dispersive x-ray spectroscopy (EDX), fourier transform infrared spectroscopy (FT-IR), powder x-ray diffraction (PXRD) and Brunauer-Emmett-Teller (BET) were employed to characterize the structure of ssCGP. ssCGP have regular hexahedron shape with edge length about 200-400 nm. Excellent ability of drug adsorption was achieved by using doxorubicin (DOX) as a model drug. The GSH triggered drug release of ssCGP was observed both in GSH contained solutions and intracellular environments. ssCGP have been demonstrated as a biocompatible porous nanocarrier, particular for intracellular drug delivery.

Bioinspired Self-Healing Hydrogel Based on Benzoxaborole-Catechol Dynamic Covalent Chemistry for 3D Cell Encapsulation

Boronic ester, one typical example of dynamic covalent bonds, has presented great potential to prepare self-healing hydrogels. However, most of currently reported hydrogels based on boronic esters are formed at pH > 8, which impeded their further use in physiological conditions. In this study, we designed two kinds of zwitterionic copolymers with benzoxaborole and catechol pendant groups, respectively. Owing to the lower pK_a value of benzoxaborole (7.2), gelation can happen easily at pH 7.4 PBS after mixing these two copolymers due to efficient formation of benzoxaborole-catechol complexations. The resulting hydrogels exhibited excellent self-healing property as well as dual pH/sugar responsiveness due to the dynamic nature of boronic ester. Moreover, benefiting from the cell membrane bioinspired 2-methacryloyloxyethyl phosphorylcholine (MPC)-based polymeric matrix, the hydrogel was further investigated for 3D cell encapsulation. The combination of biocompatible zwitterionic polymers with dynamic benzoxaborole-catechol complexation makes the hydrogels a promising platform for diverse potential bioapplications like drug delivery and tissue engineering.

Recent advances in "smart" delivery systems for extended drug release in cancer therapy

Advances in nanomedicine have become indispensable for targeted drug delivery, early detection, and increasingly personalized approaches to cancer treatment. Nanoparticle-based drug-delivery systems have overcome some of the limitations associated with traditional cancer-therapy administration, such as reduced drug solubility, chemoresistance, systemic toxicity, narrow therapeutic indices, and poor oral bioavailability. Advances in the field of nanomedicine include “smart” drug delivery, or multiple levels of targeting, and extended-release drug-delivery systems that provide additional methods of overcoming these limitations. More recently, the idea of combining smart drug delivery with extended-release has emerged in hopes of developing highly efficient nanoparticles with improved delivery, bioavailability, and safety profiles. Although functionalized and extended-release drug-delivery systems have been studied extensively, there remain gaps in the literature concerning their application in cancer treatment. We aim to provide an overview of smart and extended-release drug-delivery systems for the delivery of cancer therapies, as well as to introduce innovative advancements in nanoparticle design incorporating these principles. With the growing need for increasingly personalized medicine in cancer treatment, smart extended-release nanoparticles have the potential to enhance chemotherapy delivery, patient adherence, and treatment outcomes in cancer patients.

A sequence-activated AND logic dual-channel fluorescent probe for tracking programmable drug release

The translation of biomarker sensing into programmable diagnostics or therapeutic applications in vivo is greatly challenging, especially for eliminating the 'false positive' signals from OR logic gates. Herein we present a sense-of-logic dual-channel nanoprobe, operating through a sequence-activated AND logic gate by responding ultra-sensitively to pH changes and being subsequently triggered with biothiol for the controllable release of anti-cancer drugs. Specifically, programmable drug release is conducted in a multistage tumor microenvironment (acidic endocytic organelles followed by abnormal glutathione-overexpressing cell cytosol), which is synchronous with dual-channel near-infrared (NIR) fluorescence output. This approach represents the merging of sensing and release, including logically enabled molecular design, biomarker sensing, and controllable drug release. Impressively, the sequential AND logic feature within an unprecedented framework provides feedback on the diversity and complexity of biological milieu, along with remarkably enhancing the tumor therapeutic efficiency via its precise targeting ability and programmable drug release.

Molecularly precise self-assembly of theranostic nanoprobes within a single-molecular framework for in vivo tracking of tumor-specific chemotherapy

Structural heterogeneity and the lack of in vivo real-time tracking of drug release are the utmost barriers for nanocarrier-mediated prodrugs in targeted therapy. Herein, we describe the strategy of molecularly precise self-assembly of monodisperse nanotheranostics for BP n -DCM-S-CPT (n = 0, 5 and 20) with fixed drug loadings (36%, 23% and 16%) and constant release capacities, permitting in vivo real-time targeted therapy. We focus on regulating the hydrophilic fragment length to construct stable, well-defined nanostructured assemblies. Taking the bis-condensed dicyanomethylene-4H-pyran (DCM) derivative as the activatable near-infrared (NIR) fluorophore, it makes full use of two terminal conjunctions: the hydrophobic disulfide-bridged anticancer prodrug camptothecin (CPT) and the hydrophilic oligomer-bridged biotin segment serving as an active targeting unit. From the rational design, only BP20-DCM-S-CPT forms uniform and highly stable self-assemblies (ca. 80 nm, critical micelle concentration = 1.52 μM) with several advantages, such as structural homogeneity, fixed drug loading efficiency, real-time drug release tracking and synergistic targeting (passive, active and activatable ability). More importantly, in vitro and in vivo experiments verify that the surface-grafted biotins of nanoassemblies are directly exposed to receptors on cancer cells, thus markedly facilitating cellular internalization. Notably, through synergistic targeting, BP20-DCM-S-CPT displays excellent tumor-specific drug release performance in HeLa tumor-bearing nude mice, which has significantly enhanced in vivo antitumor activity and nearly eradicates the tumor (IRT = 99.7%) with few side effects. For the first time, the specific molecularly precise self-assembly of BP20-DCM-S-CPT within a single-molecular framework has successfully achieved a single reproducible entity for real-time reporting of drug release and cancer therapeutic efficacy in living animals, providing a new insight into amphiphilic nanotheranostics for clinical translation.

Controlled self-assembly into diverse stimuli-responsive microstructures: from microspheres to branched cylindrical micelles and vesicles

A series of amphiphilic PDMAEMA-SS-PCL chains with variable ratios of hydrophilic poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) to hydrophobic poly(ε-caprolactone) (PCL) were prepared via ring-opening polymerization, in which the two different moieties were linked via a disulfide bond with reduction responsiveness. After cross-linking by the photodegradable o-nitrobenzyl linkage, the amphiphilic chains could self-assemble into microspheres, branched cylindrical micelles and vesicles, which were responsive to the reduction agent dl-dithiothreitol and UV light irradiation through different mechanisms.

Dual-responsive dithio-polydopamine coated porous CeO2 nanorods for targeted and synergistic drug delivery

Objective

The aim was to produce the first report of assembling degradable stimuli-responsive dithio-polydopamine coating with a cancer target unit for synergistic and targeted drug delivery.

Methods

A multifunctional drug delivery system was constructed by coating a dual-responsive dithio-polydopamine (PDS) on porous CeO₂ nanorods and subsequent conjugation of lactose derivative, where the PDS was formed by self-polymerization of dithio-dopamine (DOPASS).

Results

The multifunctional drug delivery system displayed excellent cancer targeted ability resulting from the conjugation of lactose derivative, which could specifically recognize the overexpressed asialoglycoprotein receptors on the surface of HepG2 cells. It also showed a dual-responsive property of glutathione and pH, achieving controllable drug release from the cleavage of disulfide bond and subsequent degradation of PDS in cancer cells. Moreover, the degradation of PDS led to the exposure of CeO₂ nanorods, which has a synergistic anticancer effect due to its cytotoxicity to cancer cells.

Conclusion

This work presents a good example of a rational design towards synergistic and targeted DDS for cancer chemotherapies.

The Attack of the Smart Particles: Should Bacteria Be Afraid?

A shocking state of affairs; the use of nanoparticles as simple carriers is dead and outdated. Stimuli-responsive nanoparticles have emerged as active participants in the therapeutic landscape, rather than inert molecule carriers. And this time they are here to join the ongoing war against an old enemy: bacteria.

Live imaging of cell membrane-localized MT1-MMP activity on a microfluidic chip

We designed an enzyme-activatable probe for real time in situ tracking of MT1-MMP activity.

A galactose-mediated targeting nanoprobe for intracellular hydroxyl radical imaging to predict drug-induced liver injury

Drug-induced liver injury (DILI) is a serious concern in modern medicine due to its unpredictability. Currently, biochemical serum markers are being used in DILI detection. However, these biomarker-based methods lack sensitivity and specificity. A high intracellular level of hydroxyl radicals (˙OH) has been regarded as an early indicator of DILI. Therefore, we proposed an ˙OH-responsive and hepatocyte-targeted nanoprobe via conjugation of carboxyfluorescein-labeled DNA and pegylated galactose on the surface of gold nanoparticles. The nanoprobe could bind to a hepatocyte-specific asialoglycoprotein receptor through galactose, and it could be internalized into liver cells. In the presence of high levels of ˙OH in DILI, the DNA could be cleaved to release carboxyfluorescein, leading to remarkable fluorescence enhancement for ˙OH detection. Confocal fluorescence imaging demonstrated that the nanoprobe could be successfully applied in monitoring high ˙OH levels resulting from acetaminophen or triptolide-induced liver injury, which may provide a simple but powerful protocol for the prediction of DILI.

A galactose-mediated targeting nanoprobe has been developed for the accurate imaging of ˙OH to predict drug-induced hepatotoxicity at an early stage.

Nano-sized paramagnetic and fluorescent fluorinated carbon fiber with high NIR absorbance for cancer chemo-photothermal therapy

We report a novel strategy to synthesize nano-sized, water-soluble and functionalized fluorinated carbon fiber oxide with high fluorescence, paramagnetism and NIR absorption for cancer chemo-photothermal therapy.

Gemcitabine–camptothecin conjugates: a hybrid prodrug for controlled drug release and synergistic therapeutics

Self-assembled small molecule prodrug loaded with gemcitabine and camptothecin and responsive to reductive tumour microenvironment for combination cancer chemotherapy.