Reactive-Oxygen-Species-Responsive Drug Delivery Systems: Promises and Challenges

ICAM-1 targeted and ROS-responsive nanoparticles for the treatment of acute lung injury

Acute lung injury (ALI) is an inflammatory disease caused by multiple factors such as infection, trauma, and chemicals. Without effective intervention during the early stages, it usually quickly progresses to acute respiratory distress syndrome (ARDS). Since ordinary pharmaceutical preparations cannot precisely target the lungs, their clinical application is limited. In response, we constructed a γ3 peptide-decorated and ROS-responsive nanoparticle system encapsulating therapeutic dexamethasone (Dex/PSB-γ3 NPs). In vitro, Dex/PSB-γ3 NPs had rapid H2O2 responsiveness, low cytotoxicity, and strong intracellular ROS removal capacity. In a mouse model of ALI, Dex/PSB-γ3 NPs accumulated at the injured lung rapidly, alleviating pulmonary edema and cytokine levels significantly. The modification of NPs by γ3 peptide achieved highly specific positioning of NPs in the inflammatory area. The ROS-responsive release mechanism ensured the rapid release of therapeutic dexamethasone at the inflammatory site. This combined approach improves treatment accuracy, and drug bioavailability, and effectively inhibits inflammation progression. Our study could effectively reduce the risk of ALI progressing to ARDS and hold potential for the early treatment of ALI.

Cleavage and Noncleavage Chemistry in Reactive Oxygen Species (ROS)-Responsive Materials for Smart Drug Delivery

The design and development of advanced drug delivery systems targeting reactive oxygen species (ROS) have gained significant interest in recent years for treating various diseases, including cancer, psychiatric diseases, cardiovascular diseases, neurological diseases, metabolic diseases, and chronic inflammations. Integrating specific chemical bonds capable of effectively responding to ROS and triggering drug release into the delivery system is crucial. In this Review, we discuss commonly used conjugation linkers (chemical bonds) and categorize them into two groups: cleavable linkers and noncleavable linkers. Our goal is to clarify their unique drug release mechanisms from a chemical perspective and provide practical organic synthesis approaches for their efficient production. We showcase numerous significant examples to demonstrate their synthesis routes and diverse applications. Ultimately, we strive to present a comprehensive overview of cleavage and noncleavage chemistry, offering insights into the development of smart drug delivery systems that respond to ROS.

Aptamer-Based Smart Targeting and Spatial Trigger-Response Drug-Delivery Systems for Anticancer Therapy

In recent years, the field of drug delivery has witnessed remarkable progress, driven by the quest for more effective and precise therapeutic interventions. Among the myriad strategies employed, the integration of aptamers as targeting moieties and stimuli-responsive systems has emerged as a promising avenue, particularly in the context of anticancer therapy. This review explores cutting-edge advancements in targeted drug-delivery systems, focusing on the integration of aptamers and stimuli-responsive platforms for enhanced spatial anticancer therapy. In the aptamer-based drug-delivery systems, we delve into the versatile applications of aptamers, examining their conjugation with gold, silica, and carbon materials. The synergistic interplay between aptamers and these materials is discussed, emphasizing their potential in achieving precise and targeted drug delivery. Additionally, we explore stimuli-responsive drug-delivery systems with an emphasis on spatial anticancer therapy. Tumor microenvironment-responsive nanoparticles are elucidated, and their capacity to exploit the dynamic conditions within cancerous tissues for controlled drug release is detailed. External stimuli-responsive strategies, including ultrasound-mediated, photo-responsive, and magnetic-guided drug-delivery systems, are examined for their role in achieving synergistic anticancer effects. This review integrates diverse approaches in the quest for precision medicine, showcasing the potential of aptamers and stimuli-responsive systems to revolutionize drug-delivery strategies for enhanced anticancer therapy.

Multifunctional Hydrogels for the Healing of Diabetic Wounds

The healing of diabetic wounds is hindered by various factors, including bacterial infection, macrophage dysfunction, excess proinflammatory cytokines, high levels of reactive oxygen species, and sustained hypoxia. These factors collectively impede cellular behaviors and the healing process. Consequently, this review presents intelligent hydrogels equipped with multifunctional capacities, which enable them to dynamically respond to the microenvironment and accelerate wound healing in various ways, including stimuli -responsiveness, injectable self-healing, shape -memory, and conductive and real-time monitoring properties. The relationship between the multiple functions and wound healing is also discussed. Based on the microenvironment of diabetic wounds, antibacterial, anti-inflammatory, immunomodulatory, antioxidant, and pro-angiogenic strategies are combined with multifunctional hydrogels. The application of multifunctional hydrogels in the repair of diabetic wounds is systematically discussed, aiming to provide guidelines for fabricating hydrogels for diabetic wound healing and exploring the role of intelligent hydrogels in the therapeutic processes.

Research progress in nano-drug delivery systems based on the characteristics of the liver cancer microenvironment

The liver cancer has microenvironmental features such as low pH, M2 tumor-associated macrophage enrichment, low oxygen, rich blood supply and susceptibility to hematotropic metastasis, high chemokine expression, enzyme overexpression, high redox level, and strong immunosuppression, which not only promotes the progression of the disease, but also seriously affects the clinical effectiveness of traditional therapeutic approaches. However, nanotechnology, due to its unique advantages of size effect and functionalized modifiability, can be utilized to develop various responsive nano-drug delivery system (NDDS) by using these characteristic signals of the liver cancer microenvironment as a source of stimulation, which in turn can realize the intelligent release of the drug under the specific microenvironment, and significantly increase the concentration of the drug at the target site. Therefore, researchers have designed a series of stimuli-responsive NDDS based on the characteristics of the liver cancer microenvironment, such as hypoxia, weak acidity, and abnormal expression of proteases, and they have been widely investigated for improving anti-tumor therapeutic efficacy and reducing the related side effects. This paper provides a review of the current application and progress of NDDS developed based on the response and regulation of the microenvironment in the treatment of liver cancer, compares the effects of the microenvironment and the NDDS, and provides a reference for building more advanced NDDS.

Synergistic anti-oxidant and anti-inflammatory effects of ceria/resatorvid co-decorated nanoparticles for acute lung injury therapy

BACKGROUND

Acute lung injury (ALI) is a critical inflammatory response syndrome that rapidly develops into acute respiratory distress syndrome (ARDS). Currently, no effective therapeutic modalities are available for patients with ALI/ARDS. According to recent studies, inhibiting both the release of pro-inflammatory cytokines and the formation of reactive oxygen species (ROS) as early as possible may be a promising therapy for ALI.

RESULTS

In this study, a ROS-responsive nano-delivery system based on oxidation-sensitive chitosan (Ox-CS) was fabricated for the simultaneous delivery of Ce NPs and RT. The in vitro experiments have shown that the Ox-CS/Ceria-Resatorvid nanoparticles (Ox-CS/CeRT NPs) were rapidly and efficiently internalised by inflammatory endothelial cells. Biological evaluations validated the significant attenuation of ROS-induced oxidative stress and cell apoptosis by Ox-CS/CeRT NPs, while maintaining mitochondrial function. Additionally, Ox-CS/CeRT NPs effectively inhibited the release of pro-inflammatory factors. After intraperitoneal (i.p.) administration, Ox-CS/CeRT NPs passively targeted the lungs of LPS-induced inflamed mice and released the drug activated by the high ROS levels in inflammatory tissues. Finally, Ox-CS/CeRT NPs significantly alleviated LPS-induced lung injury through inhibiting both oxidative stress and pro-inflammatory cytokine expression.

CONCLUSIONS

The created Ox-CS/CeRT NPs could act as a prospective nano-delivery system for a combination of anti-inflammatory and anti-oxidant therapy of ALI.

Stimuli-Responsive Polymer-Based Nanosystems for Cancer Theranostics

Stimuli-responsive polymers can respond to internal stimuli, such as reactive oxygen species (ROS), glutathione (GSH), and pH, biological stimuli, such as enzymes, and external stimuli, such as lasers and ultrasound, etc., by changing their hydrophobicity/hydrophilicity, degradability, ionizability, etc., and thus have been widely used in biomedical applications. Due to the characteristics of the tumor microenvironment (TME), stimuli-responsive polymers that cater specifically to the TME have been extensively used to prepare smart nanovehicles for the targeted delivery of therapeutic and diagnostic agents to tumor tissues. Compared to conventional drug delivery nanosystems, TME-responsive nanosystems have many advantages, such as high sensitivity, broad applicability among different tumors, functional versatility, and improved biosafety. In recent years, a great deal of research has been devoted to engineering efficient stimuli-responsive polymeric nanosystems, and significant improvement has been made to both cancer diagnosis and therapy. In this review, we summarize some recent research advances involving the use of stimuli-responsive polymer nanocarriers in drug delivery, tumor imaging, therapy, and theranostics. Various chemical stimuli will be described in the context of stimuli-responsive nanosystems. Accordingly, the functional chemical groups responsible for the responsiveness and the strategies to incorporate these groups into the polymer will be discussed in detail. With the research on this topic expending at a fast pace, some innovative concepts, such as sequential and cascade drug release, NIR-II imaging, and multifunctional formulations, have emerged as popular strategies for enhanced performance, which will also be included here with up-to-date illustrations. We hope that this review will offer valuable insights for the selection and optimization of stimuli-responsive polymers to help accelerate their future applications in cancer diagnosis and treatment.

Diselenium-linked dimeric prodrug nanomedicine breaking the intracellular redox balance for triple-negative breast cancer targeted therapy

Triple-negative breast cancer (TNBC) has been regarded as the strongest malignancy in cases of breast cancer with a poor prognosis. The development of effective treatment strategies for TNBC has always been an urgent and unmet need. The intracellular redox balance is essential for maintaining TNBC cell malignancy. Disrupting intracellular redox balance by enlarging reactive oxygen species (ROS) generation and facilitating glutathione (GSH) depletion to amplify intracellular oxidative stress may be an alternative strategy to eliminate TNBC cells. However, inducing ROS generation and GSH depletion concurrently may be challenging. Herein, a diselenium linked-dimeric prodrug nanomedicine FA-SeSe-NPs was developed to break the intracellular redox homeostasis for TNBC targeted therapy. The dimeric prodrug was synthesized by conjugating two cucurbitacin B (CuB) molecules via one diselenium bond, which was subsequently assembled with FA-PEG-DSPE to form the final nanomedicine FA-SeSe-NPs. Using the active targeting potential of folic acid (FA), FA-SeSe-NPs could accumulate in tumor tissue with elevated levels and then be specifically internalized by cancer cells. In the high ROS and GSH conditions of TNBC cells, the diselenium bond can specifically respond to ROS to produce selenium free radicals to increase ROS and react with GSH to generate S-Se bond to deplete GSH. The released CuB further induced ROS production in TNBC cells. The diselenium bond and CuB functioned synergistically to amplify oxidative stress to kill the TNBC cells. Here, we provide a promising strategy to disrupt the intracellular redox balance of cancer cells for effective TNBC therapy.

Biomaterials-mediated targeted therapeutics of myocardial ischemia-reperfusion injury

Reperfusion therapy is widely used to treat acute myocardial infarction. However, its efficacy is limited by myocardial ischemia-reperfusion injury (MIRI), which occurs paradoxically due to the reperfusion therapy and contributes to the high mortality rate of acute myocardial infarction. Systemic administration of drugs, such as antioxidant and anti-inflammatory agents, to reduce MIRI is often ineffective due to the inadequate release at the pathological sites. Functional biomaterials are being developed to optimize the use of drugs by improving their targetability and bioavailability and reducing side effects, such as gastrointestinal irritation, thrombocytopenia, and liver damage. This review provides an overview of controlled drug delivery biomaterials for treating MIRI by triggering antioxidation, calcium ion overload inhibition, and/or inflammation regulation mechanisms and discusses the challenges and potential applications of these treatments clinically.

Supramolecular Nano-Assembly of Caffeate-Strengthened Phenylboronic Ester with Multistep ROS Scavenging Ability for Targeted Therapy of Acute Kidney Injury

Acute kidney injury (AKI) is a life-threatening complication with a considerable occurrence among patients. AKI is typically accompanied by an elevation in reactive oxidative species (ROS) in renal tissues, which is the main contributor to kidney damage. Herein, a supramolecular nano-assembly (Ser-HPEC) containing an ethyl caffeate-strengthened phenylboronic ester with ROS-triggered antioxidative ability is proposed for AKI-targeted therapy. Nano-assemblies can rapidly accumulate in the ischemia-reperfusion-injured kidney via kidney injury molecule-1 (Kim-1)-mediated homing ability of l-serine. By consuming pathological levels of ROS, two different antioxidants, ethyl caffeate and 4-hydroxybenzyl alcohol, are spontaneously released from a single module to relieve oxidative stress and diminish acute inflammation in injured renal tissue. The multistep ROS scavenging strategy combined with a precise targeting capability endows the aforementioned nano-assembly with effectiveness in preserving the integrity and functions of the injured kidney, providing new inspiration for the treatment of inflammatory diseases, including AKI.

Paclitaxel-loaded ROS-responsive nanoparticles for head and neck cancer therapy

High intracellular reactive oxygen species (ROS) level is characteristic of cancer cells and could act as a target for the efficient targeted drug delivery for cancer treatment. Consequently, biomaterials that react to excessive levels of ROS are essential for biomedical applications. In this study, a novel ROS-responsive polymer based on D-α-Tocopheryl polyethylene glycol 1000 succinate (TPGS) and poly (β-thioester) (TPGS-PBTE) was synthesized for targeted delivery of the first-line antineoplastic drug, paclitaxel (PTX). The resultant TPGS-PBTE NPs showed good ROS-responsive capability in size change and drug release. Compared to PTX, PTX-loaded nanoparticles (PTX@TPGS-PBTE NPs) showed enhanced cytotoxicity and higher level of apoptosis toward squamous cell carcinoma (SCC-7) cells. Tumor-targeted delivery of the NPs was also observed, especially after being modified with a tumor-targeting peptide, cRGD. Enhanced tumor growth inhibition was also observed in head and neck cancer SCC-7 murine models. In summary, PTX@TPGS-PBTE NPs can achieve good therapeutic effects of PTX against head and neck cancer both in vitro and in vivo, especially when modified by cRGD for active targeting, which enriched the application of ROS responsive system utilized in the delivery of anticancer drugs.

Bimodal modulation of in vitro angiogenesis with photoactive polymer nanoparticles

Angiogenesis is a fundamental process in biology, given the pivotal role played by blood vessels in providing oxygen and nutrients to tissues, thus ensuring cell survival. Moreover, it is critical in many life-threatening pathologies, like cancer and cardiovascular diseases. In this context, conventional treatments of pathological angiogenesis suffer from several limitations, including low bioavailability, limited spatial and temporal resolution, lack of specificity and possible side effects. Recently, innovative strategies have been explored to overcome these drawbacks based on the use of exogenous nano-sized materials and the treatment of the endothelial tissue with optical or electrical stimuli. Here, conjugated polymer-based nanoparticles are proposed as exogenous photo-actuators, thus combining the advantages offered by nanotechnology with those typical of optical stimulation. Light excitation can achieve high spatial and temporal resolution, while permitting minimal invasiveness. Interestingly, the possibility to either enhance (≈+30%) or reduce (up to -65%) the angiogenic capability of model endothelial cells is demonstrated, by employing different polymer beads, depending on the material type and the presence/absence of the light stimulus. In vitro results reported here represent a valuable proof of principle of the reliability and efficacy of the proposed approach and should be considered as a promising step towards a paradigm shift in therapeutic angiogenesis.

Bioorthogonal dissociative rhenium(i) photosensitisers for controlled immunogenic cell death induction

Photosensitisers for photoimmunotherapy with high spatiotemporal controllability are rare. In this work, we designed rhenium(i) polypyridine complexes modified with a tetrazine unit via a bioorthogonally activatable carbamate linker as bioorthogonally dissociative photosensitisers for the controlled induction of immunogenic cell death (ICD). The complexes displayed increased emission intensities and singlet oxygen (1O2) generation efficiencies upon reaction with trans-cyclooct-4-enol (TCO-OH) due to the separation of the quenching tetrazine unit from the rhenium(i) polypyridine core. One of the complexes containing a poly(ethylene glycol) (PEG) group exhibited negligible dark cytotoxicity but showed greatly enhanced (photo)cytotoxic activity towards TCO-OH-pretreated cells upon light irradiation. The reason is that TCO-OH allowed the synergistic release of the more cytotoxic rhenium(i) aminomethylpyridine complex and increased 1O2 generation. Importantly, the treatment induced a cascade of events, including lysosomal dysfunction, autophagy suppression and ICD. To the best of our knowledge, this is the very first example of using bioorthogonal dissociation reactions as a trigger to realise photoinduced ICD, opening up new avenues for the development of innovative photoimmunotherapeutic agents.

Unleashing the power of porphyrin photosensitizers: Illuminating breakthroughs in photodynamic therapy

This comprehensive review provides the current trends and recent developments of porphyrin-based photosensitizers. We discuss their evolution from first-generation to third-generation compounds, including cutting-edge nanoparticle-integrated derivatives, and explores their pivotal role in advancing photodynamic therapy (PDT) for enhanced cancer treatment. Integrating porphyrins with nanoparticles represents a promising avenue, offering improved selectivity, reduced toxicity, and heightened biocompatibility. By elucidating recent breakthroughs, innovative methodologies, and emerging applications, this review provides a panoramic snapshot of the dynamic field, addressing challenges and charting prospects. With a focus on harnessing reactive oxygen species (ROS) through light activation, PDT serves as a minimally invasive therapeutic approach. This article offers a valuable resource for researchers, clinicians, and PDT enthusiasts, highlighting the potential of porphyrin photosensitizers to improve the future of cancer therapy.

Smart stimuli-responsive drug delivery systems in spotlight of COVID-19

The world has been dealing with a novel severe acute respiratory syndrome (SARS-CoV-2) since the end of 2019, which threatens the lives of many people worldwide. COVID-19 causes respiratory infection with different symptoms, from sneezing and coughing to pneumonia and sometimes gastric symptoms. Researchers worldwide are actively developing novel drug delivery systems (DDSs), such as stimuli-responsive DDSs. The ability of these carriers to respond to external/internal and even multiple stimuli is essential in creating "smart" DDS that can effectively control dosage, sustained release, individual variations, and targeted delivery. To conduct a comprehensive literature survey for this article, the terms "Stimuli-responsive", "COVID-19″ and "Drug delivery" were searched on databases/search engines like "Google Scholar", "NCBI", "PubMed", and "Science Direct". Many different types of DDSs have been proposed, including those responsive to various exogenous (light, heat, ultrasound and magnetic field) or endogenous (microenvironmental changes in pH, ROS and enzymes) stimuli. Despite significant progress in DDS research, several challenging issues must be addressed to fill the gaps in the literature. Therefore, this study reviews the drug release mechanisms and applications of endogenous/exogenous stimuli-responsive DDSs while also exploring their potential with respect to COVID-19.

Nano-injectable pH/NIR-responsive hydrogel for chemo-photothermal synergistic drug delivery

Conventional cancer treatments are highly toxic and ineffective; therefore, it is essential to develop less toxic and minimally invasive treatment methods. A pH/Near Infra-red (NIR) dual-responsive, nano-injectable smart hydrogel was fabricated by incorporating CuS nanoparticles into the hydrogel networks formed by a random copolymer of N-isopropylacrylamide (NIPAM) and double-bond functionalized uracil. Microstructural characterizations of synthesized polymer and hydrogels were carried out using transmission electron microscope (TEM), scanning electron microscope (SEM), nuclear magnetic resonance (NMR) and fourier transform infrared spectroscopy (FT-IR). Multiple hydrogen bonding interactions between uracils function as physical cross-linking points to construct the network structure of the polymeric nanogel without the addition of additional cross-linking agents, ensuring the material's safety. The amino group on the structure of uracil gives the uracil-modified polymeric hydrogel excellent pH responsiveness. Notably, as a temperature-responsive material, poly (N-isopropylacrylamide) (PNIPAM) nanogel solution can achieve in situ gel formation (within 100 s at 37°C) above its lower critical solution temperature (LCST), granting injectability to polymeric solutions. Moreover, using a hierarchical construction strategy, the variable loading of DOX and CuS was achieved. First, a heterogeneous system was created by encapsulating doxorubicin (DOX) inside the nanogel via hydrophobic and π-π stacking interactions, followed by the introduction of CuS nanoparticles as photosensitizers outside of the nanogels. Due to the presence of CuS nanoparticles, the gel is able to convert NIR light into local heat to enhance the destruction of tumor cells while simultaneously achieving rapid in situ gel formation. The in situ-forming hydrogel showed promising tissue biocompatibility. The in vitro antitumor test demonstrated the capacity of the nanocomposite hydrogel for chemo-photothermal synergistic therapy. Therefore, this prepared platform has the potential to become a safe and effective, smart-responsive drug carrier for chemotherapy and PTT synergy, a minimally invasive material for tumor treatment.

Advances in Bioresorbable Triboelectric Nanogenerators

With the growing demand for next-generation health care, the integration of electronic components into implantable medical devices (IMDs) has become a vital factor in achieving sophisticated healthcare functionalities such as electrophysiological monitoring and electroceuticals worldwide. However, these devices confront technological challenges concerning a noninvasive power supply and biosafe device removal. Addressing these challenges is crucial to ensure continuous operation and patient comfort and minimize the physical and economic burden on the patient and the healthcare system. This Review highlights the promising capabilities of bioresorbable triboelectric nanogenerators (B-TENGs) as temporary self-clearing power sources and self-powered IMDs. First, we present an overview of and progress in bioresorbable triboelectric energy harvesting devices, focusing on their working principles, materials development, and biodegradation mechanisms. Next, we examine the current state of on-demand transient implants and their biomedical applications. Finally, we address the current challenges and future perspectives of B-TENGs, aimed at expanding their technological scope and developing innovative solutions. This Review discusses advancements in materials science, chemistry, and microfabrication that can advance the scope of energy solutions available for IMDs. These innovations can potentially change the current health paradigm, contribute to enhanced longevity, and reshape the healthcare landscape soon.

Current Advances in Nanotheranostics for Molecular Imaging and Therapy of Cardiovascular Disorders

Cardiovascular diseases (CVDs) refer to a collection of conditions characterized by abnormalities in the cardiovascular system. They are a global problem and one of the leading causes of mortality and disability. Nanotheranostics implies to the combination of diagnostic and therapeutic capabilities inside a single nanoscale platform that has allowed for significant advancement in cardiovascular diagnosis and therapy. These advancements are being developed to improve imaging capabilities, introduce personalized therapies, and boost cardiovascular disease patient treatment outcomes. Significant progress has been achieved in the integration of imaging and therapeutic capabilities within nanocarriers. In the case of cardiovascular disease, nanoparticles provide targeted delivery of therapeutics, genetic material, photothermal, and imaging agents. Directing and monitoring the movement of these therapeutic nanoparticles may be done with pinpoint accuracy by using imaging modalities such as cardiovascular magnetic resonance (CMR), computed tomography (CT), positron emission tomography (PET), photoacoustic/ultrasound, and fluorescence imaging. Recently, there has been an increasing demand of noninvasive for multimodal nanotheranostic platforms. In these platforms, various imaging technologies such as optical and magnetic resonance are integrated into a single nanoparticle. This platform helps in acquiring more accurate descriptions of cardiovascular diseases and provides clues for accurate diagnosis. Advances in surface functionalization methods have strengthened the potential application of nanotheranostics in cardiovascular diagnosis and therapy. In this Review, we have covered the potential impact of nanomedicine on CVDs. Additionally, we have discussed the recently developed various nanoparticles for CVDs imaging. Moreover, advancements in the CMR, CT, PET, ultrasound, and photoacoustic imaging for the CVDs have been discussed. We have limited our discussion to nanomaterials based clinical trials for CVDs and their patents.

Pleiotropic Microenvironment Remodeling Micelles for Cerebral Ischemia-Reperfusion Injury Therapy by Inhibiting Neuronal Ferroptosis and Glial Overactivation

Reperfusion injury presents a significant obstacle to neuronal survival following successful recanalization in ischemic stroke, which is characterized by intricate pathophysiological processes comprising numerous interconnected pathways. Oxidative stress-induced neuronal ferroptosis and the overactivation of glial cells play important roles in this phenomenon. In this study, we developed a targeted cross-linked micelle loaded with idebenone to rescue the ischemic penumbra by inhibiting neuronal ferroptosis and glial overactivation. In rat models, the CREKA peptide-modified micelles accumulate in the damaged brain via binding to microthrombi in the ipsilateral microvessels. Upon reactive oxygen species (ROS) stimulation, diselenide bonds within the micelles are transformed to hydrophilic seleninic acids, enabling synchronized ROS consumption and responsive drug release. The released idebenone scavenges ROS, prevents oxidative stress-induced neuronal ferroptosis, attenuates glial overactivation, and suppresses pro-inflammatory factors secretion, thereby modulating the inflammatory microenvironment. Finally, this micelle significantly reinforces neuronal survival, reduces infarct volume, and improves behavioral function compared to the control groups. This pleiotropic therapeutic micelle provides a proof-of-concept of remodeling the lesion microenvironment by inhibiting neuronal ferroptosis and glial overactivation to treat cerebral ischemia-reperfusion injury.

X-Ray-Induced Drug Release for Cancer Therapy

Drug delivery systems (DDSs) are designed to deliver therapeutic agents to specific target sites while minimizing systemic toxicity. Recent developments in drug-loaded DDSs have demonstrated promising characteristics and paved new pathways for cancer treatment. Light, a prevalent external stimulus, is widely utilized to trigger drug release. However, conventional light sources primarily concentrate on the ultraviolet (UV) and visible light regions, which suffer from limited biological tissue penetration. This limitation hinders applications for deep-tissue tumor drug release. Given their deep tissue penetration and well-established application technology, X-rays have recently received attention for the pursuit of controlled drug release. With precise spatiotemporal and dosage controllability, X-rays stand as an ideal stimulus for achieving controlled drug release in deep-tissue cancer therapy. This article explores the recent advancements in using X-rays for stimulus-triggered drug release in DDSs and delves into their action mechanisms.

Smart and versatile biomaterials for cutaneous wound healing

The global increase of cutaneous wounds imposes huge health and financial burdens on patients and society. Despite improved wound healing outcomes, conventional wound dressings are far from ideal, owing to the complex healing process. Smart wound dressings, which are sensitive to or interact with changes in wound condition or environment, have been proposed as appealing therapeutic platforms to effectively facilitate wound healing. In this review, the wound healing processes and features of existing biomaterials are firstly introduced, followed by summarizing the mechanisms of smart responsive materials. Afterwards, recent advances and designs in smart and versatile materials of extensive applications for cutaneous wound healing were submarined. Finally, clinical progresses, challenges and future perspectives of the smart wound dressing are discussed. Overall, by mapping the composition and intrinsic structure of smart responsive materials to their individual needs of cutaneous wounds, with particular attention to the responsive mechanisms, this review is promising to advance further progress in designing smart responsive materials for wounds and drive clinical translation.

Recent Advances of Platinum-Based Anticancer Complexes in Combinational Multimodal Therapy

Platinum drugs with manifest therapeutic effects are widely used, but their systemic toxicity and the drug resistance acquired by cancer cells limit their clinical applications. Thus, the exploration on appropriate methods and strategies to overcome the limitations of traditional platinum drugs becomes extremely necessary. Combination therapy of platinum drugs can inhibit tumor growth and metastasis in an additive or synergistic manner, and can potentially reduce the systemic toxicity of platinum drugs and overcome platinum-resistance. This review summarizes the various modalities and current progress in platinum-based combination therapy. The synthetic strategies and therapeutic effects of some platinum-based anticancer complexes in the combination of platinum drugs with gene editing, ROS-based therapy, thermal therapy, immunotherapy, biological modelling, photoactivation, supramolecular self-assembly and imaging modality are briefly described. Their potential challenges and prospects are also discussed. It is hoped that this review will inspire researchers to have more ideas for the future development of highly effective platinum-based anti-cancer complexes.

Mussel-inspired self-healing hydrogel form pectin and cellulose for hemostasis and diabetic wound repairing

Diabetic wound is considered as a kind of chronic wound prone to infection and difficult to repair due to high glucose level in the blood of patients. In this research, a biodegradable self-healing hydrogel with mussel inspired bioadhesion and anti-oxidation properties is fabricated based on Schiff-base cross-linking. The hydrogel was designed from dopamine coupled pectin hydrazide (Pec-DH) and oxidized carboxymethyl cellulose (DCMC) for mEGF loading as a diabetic wound repair dressing. The Pectin and CMC as natural feedstock endowed the hydrogel with biodegradability to avoid possible side effects, while the coupled catechol structure could enhance the tissue adhesion of the hydrogel for hemostasis. The results showed the Pec-DH/DCMC hydrogel formed fast and can cover irregular wounds with good sealing effect. The catechol structure also improved the reactive oxygen species (ROS) scavenging ability of the hydrogel, which can eliminate the negative effect of ROS during wound healing. The in vivo diabetic wound healing experiment revealed the hydrogel as mEGF loading vehicle greatly enhanced the diabetic wound repairing rate in mice model. As a result, the Pec-DH/DCMC hydrogel could show advantages as EGF carrier in wound healing applications.

Peroxide-Mediated Release of Organophosphates from Boron-Containing Phosphotriesters: A New Class of Organophosphate Prodrugs

Phosphate mono- and diesters can be liberated efficiently from boryl allyloxy (BAO) and related phosphotriesters by H2O2. This protocol was applied to the release of a phosphorylated serine derivative and the nucleotide analogue AZT monophosphate. Nucleotide release in the presence of ATP and a kinase provides a diphosphate, demonstrating that this method can be applied to biological processes.

Dual-Ligand Synergistic Targeting Anti-Tumor Nanoplatforms with Cascade-Responsive Drug Release

Dual-ligand targeting drug delivery nanoplatforms are considered a promising tool for enhancing the specificity of chemotherapy. However, serious off-target delivery has been observed in current dual-ligand targeting nanoplatforms, as each ligand can independently recognize receptors on the cell membrane surface and guide drug nanocarriers to different cells. To overcome this barrier, a dual-ligand synergistic targeting (DLST) nanoplatform is developed, which can guide chemotherapy treatment specifically to cancer cells simultaneously overexpressing two receptors. This nanoplatform consists of a singlet oxygen (¹O₂) photosensitizer-loaded nanocarrier and a drug-loaded nanocarrier with ¹O₂ responsiveness, which were, respectively, decorated with a pair of complementary DNA sequences and two different ligands. For cancer cells overexpressing both receptors, two nanocarriers can be internalized in larger quantities to cause DNA hybridization-induced nanocarrier aggregation, which further activates ¹O₂-triggered drug release under light irradiation. For cells overexpressing a single receptor, only one type of nanocarrier can be internalized in a large quantity, leading to blocked drug release due to the ultrashort action radius of ¹O₂. In vivo evaluation showed this DLST nanoplatform displayed highly specific tumor treatment with minimized long-term toxicity. This is a highly efficient drug delivery system for DLST chemotherapy, holding great potential for clinical applications.

Phototriggered structures: Latest advances in biomedical applications

Non-invasive control of the drug molecules accessibility is a key issue in improving diagnostic and therapeutic procedures. Some studies have explored the spatiotemporal control by light as a peripheral stimulus. Phototriggered drug delivery systems (PTDDSs) have received interest in the past decade among biological researchers due to their capability the control drug release. To this end, a wide range of phototrigger molecular structures participated in the DDSs to serve additional efficiency and a high-conversion release of active fragments under light irradiation. Up to now, several categories of PTDDSs have been extended to upgrade the performance of controlled delivery of therapeutic agents based on well-known phototrigger molecular structures like o-nitrobenzyl, coumarinyl, anthracenyl, quinolinyl, o-hydroxycinnamate and hydroxyphenacyl, where either of one endows an exclusive feature and distinct mechanistic approach. This review conveys the design, photochemical properties and essential mechanism of the most important phototriggered structures for the release of single and dual (similar or different) active molecules that have the ability to quickly reason of the large variety of dynamic biological phenomena for biomedical applications like photo-regulated drug release, synergistic outcomes, real-time monitoring, and biocompatibility potential.

Cancer Metabolism: The Role of ROS in DNA Damage and Induction of Apoptosis in Cancer Cells

Cancer is a huge challenge for people worldwide. High reactive oxygen species (ROS) levels are a recognized hallmark of cancer and an important aspect of cancer treatment research. Abnormally elevated ROS levels are often attributable to alterations in cellular metabolic activities and increased oxidative stress, which affects both the development and maintenance of cancer. Moderately high levels of ROS are beneficial to maintain tumor cell genesis and development, while toxic levels of ROS have been shown to be an important force in destroying cancer cells. ROS has become an important anticancer target based on the proapoptotic effect of toxic levels of ROS. Therefore, this review summarizes the role of increased ROS in DNA damage and the apoptosis of cancer cells caused by changes in cancer cell metabolism, as well as various anticancer therapies targeting ROS generation, in order to provide references for cancer therapies based on ROS generation.

Spatiotemporally controlled drug delivery via photothermally driven conformational change of self-integrated plasmonic hybrid nanogels

BACKGROUND

Spatiotemporal regulation is one of the major considerations for developing a controlled and targeted drug delivery system to treat diseases efficiently. Light-responsive plasmonic nanostructures take advantage due to their tunable optical and photothermal properties by changing size, shape, and spatial arrangement.

RESULTS

In this study, self-integrated plasmonic hybrid nanogels (PHNs) are developed for spatiotemporally controllable drug delivery through light-driven conformational change and photothermally-boosted endosomal escape. PHNs are easily synthesized through the simultaneous integration of gold nanoparticles (GNPs), thermo-responsive poly (N-isopropyl acrylamide), and linker molecules during polymerization. Wave-optic simulations reveal that the size of the PHNs and the density of the integrated GNPs are crucial factors in modulating photothermal conversion. Several linkers with varying molecular weights are inserted for the optimal PHNs, and the alginate-linked PHN (A-PHN) achieves more than twofold enhanced heat conversion compared with others. Since light-mediated conformational changes occur transiently, drug delivery is achieved in a spatiotemporally controlled manner. Furthermore, light-induced heat generation from cellular internalized A-PHNs enables pinpoint cytosolic delivery through the endosomal rupture. Finally, the deeper penetration for the enhanced delivery efficiency by A-PHNs is validated using multicellular spheroid.

CONCLUSION

This study offers a strategy for synthesizing light-responsive nanocarriers and an in-depth understanding of light-modulated site-specific drug delivery.

Targeting the Interplay of Independent Cellular Pathways and Immunity: A Challenge in Cancer Immunotherapy

Immunotherapy is a cancer treatment that exploits the capacity of the body's immune system to prevent, control, and remove cancer. Immunotherapy has revolutionized cancer treatment and significantly improved patient outcomes for several tumor types. However, most patients have not benefited from such therapies yet. Within the field of cancer immunotherapy, an expansion of the combination strategy that targets independent cellular pathways that can work synergistically is predicted. Here, we review some consequences of tumor cell death and increased immune system engagement in the modulation of oxidative stress and ubiquitin ligase pathways. We also indicate combinations of cancer immunotherapies and immunomodulatory targets. Additionally, we discuss imaging techniques, which are crucial for monitoring tumor responses during treatment and the immunotherapy side effects. Finally, the major outstanding questions are also presented, and directions for future research are described.

Nanoparticles-based phototherapy systems for cancer treatment: Current status and clinical potential

Remarkable progress in phototherapy has been made in recent decades, due to its non-invasiveness and instant therapeutic efficacy. In addition, with the rapid development of nanoscience and nanotechnology, phototherapy systems based on nanoparticles or nanocomposites also evolved as an emerging hotspot in nanomedicine research, especially in cancer. In this review, first we briefly introduce the history of phototherapy, and the mechanisms of phototherapy in cancer treatment. Then, we summarize the representative development over the past three to five years in nanoparticle-based phototherapy and highlight the design of the innovative nanoparticles thereof. Finally, we discuss the feasibility and the potential of the nanoparticle-based phototherapy systems in clinical anticancer therapeutic applications, aiming to predict future research directions in this field. Our review is a tutorial work, aiming at providing useful insights to researchers in the field of nanotechnology, nanoscience and cancer.

Smart Poly(lactide)-b-poly(triethylene glycol methyl ether methacrylate) (PLA-b-PTEGMA) Block Copolymers: One-Pot Synthesis, Temperature Behavior, and Controlled Release of Paclitaxel

This paper introduces a new class of amphiphilic block copolymers created by combining two polymers: polylactic acid (PLA), a biocompatible and biodegradable hydrophobic polyester used for cargo encapsulation, and a hydrophilic polymer composed of oligo ethylene glycol chains (triethylene glycol methyl ether methacrylate, TEGMA), which provides stability and repellent properties with added thermo-responsiveness. The PLA-b-PTEGMA block copolymers were synthesized using ring-opening polymerization (ROP) and reversible addition-fragmentation chain transfer (RAFT) polymerization (ROP-RAFT), resulting in varying ratios between the hydrophobic and hydrophilic blocks. Standard techniques, such as size exclusion chromatography (SEC) and ¹H NMR spectroscopy, were used to characterize the block copolymers, while ¹H NMR spectroscopy, 2D nuclear Overhauser effect spectroscopy (NOESY), and dynamic light scattering (DLS) were used to analyze the effect of the hydrophobic PLA block on the LCST of the PTEGMA block in aqueous solutions. The results show that the LCST values for the block copolymers decreased with increasing PLA content in the copolymer. The selected block copolymer presented LCST transitions at physiologically relevant temperatures, making it suitable for manufacturing nanoparticles (NPs) and drug encapsulation-release of the chemotherapeutic paclitaxel (PTX) via temperature-triggered drug release mechanism. The drug release profile was found to be temperature-dependent, with PTX release being sustained at all tested conditions, but substantially accelerated at 37 and 40 °C compared to 25 °C. The NPs were stable under simulated physiological conditions. These findings demonstrate that the addition of hydrophobic monomers, such as PLA, can tune the LCST temperatures of thermo-responsive polymers, and that PLA-b-PTEGMA copolymers have great potential for use in drug and gene delivery systems via temperature-triggered drug release mechanisms in biomedicine applications.

The role of crystallinity of palladium nanocrystals in ROS generation and cytotoxicity induction

Palladium (Pd) nanocrystals with different crystalline forms exhibit distinct enzyme-like activities in generating reactive oxygen species (ROS). How such crystallinity-dependent catalytic activity regulates potential cytotoxicity remains to be elucidated. In the present work, Pd nanocrystals with four different crystalline forms were synthesized, and the underlying mechanisms involved in ROS-mediated cytotoxicity were systematically revealed. Pd nanocrystals with the {100} (nanocubes) and {111} (nanooctahedrons and nanotetrahedrons) facets triggered cytotoxicity by generating singlet oxygen (¹O₂) and hydroxyl radicals (OH˙), respectively. Meanwhile, Pd nanoconcave-tetrahedrons, which had both the {110} and {111} facets, induced ROS-mediated cytotoxicity via activating the superoxide (O₂˙^-) pathway. Consumption of protons and generation of hydroxide during intracellular ROS conversion resulted in pH alkalization, eventually leading to cell death. Our findings emphasize the importance of facet-dependent ROS generation promoted by Pd nanocrystals. Furthermore, alkalization is identified as a new biomarker for analyzing ROS-mediated cytotoxicity.

Remodeling Tumor Immunogenicity with Dual-Activatable Binary CRISPR Nanomedicine for Cancer Immunotherapy

The specific recognition of cancer cells by the body's immune system is an essential step in initiating antitumor immunity. However, the decreased expression of major histocompatibility complex class I (MHC-1) and overexpression of programmed death ligand 1 (PD-L1) causes insufficient tumor-associated antigens presentation and inactivation of T cells, which accounts for poor immunogenicity. To remodel tumor immunogenicity, herein, a dual-activatable binary CRISPR nanomedicine (DBCN) that can efficiently deliver a CRISPR system into tumor tissues and specifically control its activation is reported. This DBCN is made of a thioketal-cross-linked polyplex core and an acid-detachable polymer shell, which can maintain stability during blood circulation, while detaching a polymer shell to facilitate the cellular internalization of the CRISPR system after entering tumor tissues and ultimately activating gene editing under exogenous laser irradiation, thereby maximizing the therapeutic benefits and reducing potential safety concerns. With the collaborative application of multiple CRISPR systems, DBCN efficiently corrects both dysregulation of MHC-1 and PD-L1 expression in tumors, thus initiating robust T cell-dependent antitumor immune responses to inhibit malignant tumor growth, metastasis, and recurrence. Given the increasing abundance of CRISPR toolkits, this research provides an appealing therapeutic strategy and a universal delivery platform to develop more advanced CRISPR-based cancer treatments.

A chlorogenic acid functional strategy of anti-inflammation, anti-coagulation and promoted endothelial proliferation for bioprosthetic artificial heart valves

Heart valve replacement has become an optimal choice for the treatment of severe heart valve disease. At present, most commercial bioprosthetic heart valves (BHVs) are made from porcine pericardium or bovine pericardium treated with glutaraldehyde. Nevertheless, due to the toxicity of residual aldehyde groups left after glutaraldehyde cross-linking, these commercial BHVs exhibit poor biocompatibility, calcification, risk of coagulation and endothelialization difficulty, which greatly affects the durability of the BHVs and shortens their service life. In this work, based on a chlorogenic acid functional anti-inflammation, anti-coagulation and endothelialization strategy and dual-functional non-glutaraldehyde cross-linking reagent OX-CO, a kind of functional BHV material OX-CA-PP has been developed from OX-CO cross-linked porcine pericardium (OX-CO-PP) followed by the convenient modification of chlorogenic acid through a reactive oxygen species (ROS) sensitive borate ester bond. The functionalization of chlorogenic acid can reduce the risk of valve leaf thrombosis and promote endothelial cell proliferation, which is beneficial to the formation of a long-term interface with good blood compatibility. Meanwhile, such a ROS responsive behavior can trigger intelligent release of chlorogenic acid on-demand to achieve the inhibition of acute inflammation at the early stage of implantation. The in vivo and in vitro experimental results show that the functional BHV material OX-CA-PP exhibits superior anti-inflammation, improved anti-coagulation, minimal calcification and promoted proliferation of endothelial cells, showing that this non-glutaraldehyde functional strategy has great potential for the application of BHVs and providing a promising reference for other implanted biomaterials.

Enhanced neural differentiation by applying electrical stimulation utilizing conductive and antioxidant alginate-polypyrrole/poly-l-lysine hydrogels

The challenge of restoration from neurodegenerative disorder requires effective solutions. To enhance the healing efficiencies, scaffolds with antioxidant activities, electroconductivity, and versatile features to encourage neuronal differentiation are potentially useful. Herein, polypyrrole-alginate (Alg-PPy) copolymer was used to design antioxidant and electroconductive hydrogels through the chemical oxidation radical polymerization method. The hydrogels have antioxidant effects to combat oxidative stress in nerve damage thanks to the introduction of PPy. Additionally, poly-l-lysine (PLL) provided these hydrogels with a great differentiation ability of stem cells. The morphology, porosity, swelling ratio, antioxidant activity, rheological behavior, and conductive characteristics of these hydrogels were precisely adjusted by altering the amount of PPy. Characterization of hydrogels showed appropriate electrical conductivity and antioxidant activity for neural tissue applications. Cytocompatibility, live/dead assays, and Annexin V/PI staining by flow cytometry using P19 cells confirmed the excellent cytocompatibility and cell protective effect under ROS microenvironment of these hydrogels in both normal and oxidative conditions. The neural marker investigation in the induction of electrical impulses was assessed through RT-PCR and immunofluorescence assay, demonstrating the differentiation of P19 cells to neurons cultured in these scaffolds. In summary, the antioxidant and electroconductive Alg-PPy/PLL hydrogels demonstrated excellent potential as promising scaffolds for treating neurodegenerative disorders.

Targeting active sites of inflammation using inherent properties of tissue-resident mast cells

Mast cells play a pivotal role in initiating and directing host's immune response. They reside in tissues that primarily interface with the external environment. Activated mast cells respond to environmental cues throughout acute and chronic inflammation through releasing immune mediators via rapid degranulation, or long-term de novo expression. Mast cell activation results in the rapid release of a variety of unique enzymes and reactive oxygen species. Furthermore, the increased density of mast cell unique receptors like mas related G protein-coupled receptor X2 also characterizes the inflamed tissues. The presence of these molecules (either released mediators or surface receptors) are particular to the sites of active inflammation, and are a result of mast cell activation. Herein, the molecular design principles for capitalizing on these novel mast cell properties is discussed with the goal of manipulating localized inflammation. STATEMENT OF SIGNIFICANCE: Mast cells are immune regulating cells that play a crucial role in both innate and adaptive immune responses. The activation of mast cells causes the release of multiple unique profiles of biomolecules, which are specific to both tissue and disease. These unique characteristics are tightly regulated and afford a localized stimulus for targeting inflammatory diseases. Herein, these important mast cell attributes are discussed in the frame of highlighting strategies for the design of bioresponsive functional materials to target regions of inflammations.

3D Printed Hydrogel Microneedle Arrays for Interstitial Fluid Biomarker Extraction and Colorimetric Detection

To treat and manage chronic diseases, it is necessary to continuously monitor relevant biomarkers and modify treatment as the disease state changes. Compared to other bodily fluids, interstitial skin fluid (ISF) is a good choice for identifying biomarkers because it has a molecular composition most similar to blood plasma. Herein, a microneedle array (MNA) is presented to extract ISF painlessly and bloodlessly. The MNA is made of crosslinked poly(ethylene glycol) diacrylate (PEGDA), and an optimal balance of mechanical properties and absorption capability is suggested. Besides, the effect of needles’ cross-section shape on skin penetration is studied. The MNA is integrated with a multiplexed sensor that provides a color change in a biomarker concentration-dependent manner based on the relevant reactions for colorimetric detection of pH and glucose biomarkers. The developed device enables diagnosis by visual inspection or quantitative red, green, and blue (RGB) analysis. The outcomes of this study show that MNA can successfully identify biomarkers in interstitial skin fluid in a matter of minutes. The home-based long-term monitoring and management of metabolic diseases will benefit from such practical and self-administrable biomarker detection.

Oxidation-labile linkers for controlled drug delivery

The continuous symbiosis throughout chemical biology and drug discovery has led to the design of innovative bifunctional molecules for targeted and controlled drug delivery. Among the different tools, protein-drug and peptide-drug conjugates are trend approaches to achieve targeted delivery, selectivity and efficacy. To meet the main goals of these bioconjugates, the selection of the appropriate payloads and linkers is crucial, as they must provide in vivo stability, while they may also help to achieve the therapeutic target and action. In neurodegenerative diseases or some cancer types, where oxidative stress plays an important role, linkers sensitive to oxidative conditions may be able to release the drug once the conjugate achieves the target. Considering specially this specific application, this mini-review covers the most relevant publications on oxidation-labile linkers.

Codelivery of BCL2 and MCL1 Inhibitors Enabled by Phenylboronic Acid-Functionalized Polypeptide Nanovehicles for Synergetic and Potent Therapy of Acute Myeloid Leukemia

Acute myeloid leukemia (AML) is the most refractory hematologic malignancy characterized by acute onset, rapid progression, and high recurrence rate. Here, codelivery of BCL2 (ABT199) and MCL1 (TW37) inhibitors using phenylboronic acid-functionalized polypeptide nanovehicles to achieve synergetic and potent treatment of AML is adopted. Leveraging the dynamic boronic ester bonds, BN coordination, and π-π stacking, the nanovehicles reveal remarkably efficient and robust drug coencapsulation. ABT199 can induce a series of pro-apoptotic reactions by promoting the dissociation of the pro-apoptotic protein Bim from BCL2, while the released Bim is often captured by MCL1 protein overexpressed in AML. TW37 has a strong inhibitory ability to MCL1, thereby can restrain the depletion of Bim protein. Dual inhibitor-loaded nanoparticles (NPAT) reveal excellent stability, acid/enzyme/H₂ O₂ -triggered drug release, and significant cytotoxicity toward MOLM-13-Luc and MV-411 AML cells with low half maximal inhibitory concentrations of 1.15 and 7.45 ng mL^-1 , respectively. In mice bearing MOLM-13-Luc or MV-411 AML cancer, NPAT reveal significant inhibition of tumor cell infiltration in bone marrow and main organs, potent suppression of tumor growth, and remarkably elevated mouse survival. With facile construction, varying drug combination, superior safety, synergetic efficacy, the phenylboronic acid-functionalized smart nanodrugs hold remarkable potential for AML treatment.

Peptide-guided delivery improves the therapeutic efficacy and safety of glucocorticoid drugs for treating acute lung injury

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are life-threatening conditions with excessive inflammation in the lung. Glucocorticoids had been widely used for ALI/ARDS, but their clinical benefit remains unclear. Here, we tackled the problem by conjugating prednisolone (PSL) with a targeting peptide termed CRV. Systemically administered CRV selectively homes to the inflamed lung of a murine ALI model, but not healthy organs or the lung of healthy mice. The expression of the CRV receptor, retinoid X receptor β, was elevated in the lung of ALI mice and patients with interstitial lung diseases, which may be the basis of CRV targeting. We then covalently conjugated PSL and CRV with a reactive oxygen species (ROS)-responsive linker in the middle. While being intact in blood, the ROS linker was cleaved intracellularly to release PSL for action. In vitro, CRV-PSL showed an anti-inflammatory effect similar to that of PSL. In vivo, CRV conjugation increased the amount of PSL in the inflamed lung but reduced its accumulation in healthy organs. Accordingly, CRV-PSL significantly reduced lung injury and immune-related side effects elsewhere. Taken together, our peptide-based strategy for targeted delivery of glucocorticoids for ALI may have great potential for clinical translation.

Oxidation Responsive PEGylated Polyamino Acid Bearing Thioether Pendants for Enhanced Anticancer Drug Delivery

Reactive oxygen species (ROS) in biological tissues are in a state of dynamic balance. However, many diseases such as cancer and inflammation, are accompanied by a long-term increase in ROS. This situation inspires researchers to use ROS-sensitive nanocarriers for a site-specific release of cargo in pathological areas. Polyamino acid materials with good biodegradability, biocompatibility, and regular secondary structure are widely used in the biomedical field. Herein, a new oxidation responsive PEGylated polyamino acid is synthesised for anticancer drug delivery by ring-opening polymerisation of N-carboxyanhydrides bearing thioether pendants. The obtained block copolymer mPEG-b-PMLG self-assembles into spherical nanoparticles (NPs) in water with diameter ≈68.3 nm. NMR measurement demonstrated that the hydrophobic thioether pendants in the NPs can be selectively oxidised to hydrophilic sulfoxide groups by H₂ O₂ , which will lead to the disassociation of NPs. In vitro drug release results indicated that the encapsulated Nile red is selectively released in the trigger of 10 mM H₂ O₂ in PBS. Finally, anticancer drug doxorubicin (DOX) is encapsulated to the NPs, and the obtained NPs/DOX exhibits an improved antitumor efficacy in 4T1 tumour-bearing mice and lower cardiotoxicity than free DOX. These results indicates that the mPEG-b-PMLG NPs are promising for anticancer drug delivery.

A nitric-oxide driven chemotactic nanomotor for enhanced immunotherapy of glioblastoma

The major challenges of immunotherapy for glioblastoma are that drugs cannot target tumor sites accurately and properly activate complex immune responses. Herein, we design and prepare a kind of chemotactic nanomotor loaded with brain endothelial cell targeting agent angiopep-2 and anti-tumor drug (Lonidamine modified with mitochondrial targeting agent triphenylphosphine, TLND). Reactive oxygen species and inducible nitric oxide synthase (ROS/iNOS), which are specifically highly expressed in glioblastoma microenvironment, are used as chemoattractants to induce the chemotactic behavior of the nanomotors. We propose a precise targeting strategy of brain endothelial cells-tumor cells-mitochondria. Results verified that the released NO and TLND can regulate the immune circulation through multiple steps to enhance the effect of immunotherapy, including triggering the immunogenic cell death of tumor, inducing dendritic cells to mature, promoting cytotoxic T cells infiltration, and regulating tumor microenvironment. Moreover, this treatment strategy can form an effective immune memory effect to prevent tumor metastasis and recurrence.

Graphene-based nanomaterials for stimuli-sensitive controlled delivery of therapeutic molecules

Stimuli-responsive drug delivery has attracted tremendous attention in the past decades. It provides a spatial- and temporal-controlled release in response to different triggers, thus enabling highly efficient drug delivery and minimizing drug side effects. Graphene-based nanomaterials have been broadly explored, and they show great potential in smart drug delivery due to their stimuli-responsive behavior and high loading capacity for an extended range of drug molecules. These characteristics are a result of high surface area, mechanical stability and chemical stability, and excellent optical, electrical, and thermal properties. Their great and infinite functionalization potential also allows them to be integrated into several types of polymers, macromolecules, or other nanoparticles, leading to the fabrication of novel nanocarriers with enhanced biocompatibility and trigger-sensitive properties. Thus, numerous studies have been dedicated to graphene modification and functionalization. In the current review, we introduce graphene derivatives and different graphene-based nanomaterials utilized in drug delivery and discuss the most important advances in their functionalization and modification. Also, their potential and progress in an intelligent drug release in response to different types of stimuli either endogenous (pH, redox conditions, and reactive oxygen species (ROS)) or exogenous (temperature, near-infrared (NIR) radiation, and electric field) will be debated.

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.

Employing Supervised Algorithms for the Prediction of Nanomaterial's Antioxidant Efficiency

Reactive oxygen species (ROS) are compounds that readily transform into free radicals. Excessive exposure to ROS depletes antioxidant enzymes that protect cells, leading to oxidative stress and cellular damage. Nanomaterials (NMs) exhibit free radical scavenging efficiency representing a potential solution for oxidative stress-induced disorders. This study aims to demonstrate the application of machine learning (ML) algorithms for predicting the antioxidant efficiency of NMs. We manually compiled a comprehensive dataset based on a literature review of 62 in vitro studies. We extracted NMs' physico-chemical (P-chem) properties, the NMs' synthesis technique and various experimental conditions as input features to predict the antioxidant efficiency measured by a 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. Following data pre-processing, various regression models were trained and validated. The random forest model showed the highest predictive performance reaching an R² = 0.83. The attribute importance analysis revealed that the NM's type, core-size and dosage are the most important attributes influencing the prediction. Our findings corroborate with those of the prior research landscape regarding the importance of P-chem characteristics. This study expands the application of ML in the nano-domain beyond safety-related outcomes by capturing the functional performance. Accordingly, this study has two objectives: (1) to develop a model to forecast the antioxidant efficiency of NMs to complement conventional in vitro assays and (2) to underline the lack of a comprehensive database and the scarcity of relevant data and/or data management practices in the nanotechnology field, especially with regards to functionality assessments.

Facile Fabrication of α-Bisabolol Nanoparticles with Improved Antioxidant and Antibacterial Effects

Bioactive compounds are widely used in the bio-industry because of their antioxidant and antibacterial activities. Because of excessive oxidative stress, which causes various diseases in humans, and because preservatives used in bioproducts cause allergies and contact dermatitis, it is important to use natural bioactive compounds in bioproducts to minimize oxidative stress. α-bisabolol (ABS) is a natural compound with both antioxidant and antibacterial properties. However, its water-insolubility makes its utilization in bioproducts difficult. In this study, ABS-loaded polyglyceryl-4 caprate nanoparticles (ABS@NPs) with improved aqueous stability and ABS loading were fabricated using an encapsulation method. The long-term stability of the ABS@NPs was analyzed with dynamic light scattering and methylene blue-staining to determine the optimized ABS concentration in ABS@NPs (10 wt%). The ABS@NPs exhibited excellent antioxidant activity, according to the 2,2-diphenyl-1-picrylhydrazyl assay and in vitro reactive oxygen species generation in NIH-3T3 fibroblast cells, and an outstanding antibacterial effect, as determined using the Staphylococcus aureus colony-counting method. Furthermore, we evaluated the biocompatibility of the ABS@NPs in vitro. This study suggests that ABS@NPs with improved antioxidant and antibacterial properties can be used to treat diseases related to various oxidative stresses and can be applied in many fields, such as pharmaceuticals, cosmetics, and foods.

Recent Advances in Targeted Nanocarriers for the Management of Triple Negative Breast Cancer

Triple-negative breast cancer (TNBC) is a life-threatening form of breast cancer which has been found to account for 15% of all the subtypes of breast cancer. Currently available treatments are significantly less effective in TNBC management because of several factors such as poor bioavailability, low specificity, multidrug resistance, poor cellular uptake, and unwanted side effects being the major ones. As a rapidly growing field, nano-therapeutics offers promising alternatives for breast cancer treatment. This platform provides a suitable pathway for crossing biological barriers and allowing sustained systemic circulation time and an improved pharmacokinetic profile of the drug. Apart from this, it also provides an optimized target-specific drug delivery system and improves drug accumulation in tumor cells. This review provides insights into the molecular mechanisms associated with the pathogenesis of TNBC, along with summarizing the conventional therapy and recent advances of different nano-carriers for the management of TNBC.