Biodegradable Persistent Luminescence Nanoparticles as Pyroptosis Inducer for High-Efficiency Tumor Immunotherapy

Pyroptosis possesses potent antitumor immune activity, making pyroptosis inducer development a promising direction for tumor immunotherapy. Persistent luminescence nanoparticles (PLNPs) are highly sensitive optical probes extensively employed in tumor diagnosis and therapy. However, a pyroptosis inducer based on PLNPs has not been reported yet. Herein, polyethylene glycol-poly lactic acid-co-glycolic acid (PEG-PLGA: PP) modified biodegradable CaS:Eu2+ (CSE@PP) PLNPs are synthesized as a pyroptosis inducer for tumor immunotherapy for the first time. The synthesized CSE@PP possesses biowindow persistent luminescence (PersL) and pH-responsive degradation properties, allowing it to remain stable under neutral pH but degrade when exposed to weak acid (pH < 6.5). During degradation within the tumor, CSE@PP constantly releases H2S and Ca2+ while its PersL gradually fades away. Thus, the PersL signal can self-monitor H2S and Ca2+ release. Furthermore, the released H2S and Ca2+ result in mitochondrial dysfunction and the inactivation of reactive oxygen species scavenging enzymes, synergistic facilitating intracellular oxidative stress, which induces caspase-1/GSDM-D dependent pyroptosis and subsequent antitumor immune responses. In a word, it is confirmed that CSE@PP can self-monitor H2S and Ca2+ release and pyroptosis-mediated tumor Immunotherapy. This work will facilitate biomedical applications of PLNPs and inspire pyroptosis-induced tumor immunotherapy.

Stimuli-Responsive Polymersomes: Reshaping the Immunosuppressive Tumor Microenvironment

The progression of cancer involves mutations in normal cells, leading to uncontrolled division and tissue destruction, highlighting the complexity of tumor microenvironments (TMEs). Immunotherapy has emerged as a transformative approach, yet the balance between efficacy and safety remains a challenge. Nanoparticles such as polymersomes offer the possibility to precisely target tumors, deliver drugs in a controlled way, effectively modulate the antitumor immunity, and notably reduce side effects. Herein, stimuli-responsive polymersomes, with capabilities for carrying multiple therapeutics, are highlighted for their potential in enhancing antitumor immunity through mechanisms like inducing immunogenic cell death and activating STING (stimulator of interferon genes), etc. The recent progress of utilizing stimuli-responsive polymersomes to reshape the TME is reviewed here. The advantages and limitations to applied stimuli-responsive polymersomes are outlined. Additionally, challenges and future prospects in leveraging polymersomes for cancer therapy are discussed, emphasizing the need for future research and clinical translation.

Gold Nanoparticle-Carrying T Cells for the Combined Immuno-Photothermal Therapy

Cancer immunotherapy is a promising therapy to treat cancer patients with minimal toxicity, but only a small fraction of patients responded to it as a monotherapy. In this study, a strategy to boost therapeutic efficacy by combining an immunotherapy based on ex vivo expanded tumor-reactive T cells is devised, or adoptive cell therapy (ACT), with photothermal therapy (PTT). Smart gold nanoparticles (sAuNPs), which aggregates to form gold nanoclusters in the cells, are loaded into T cells, and their photothermal effects within T cells are confirmed. When transferred into tumor-bearing mice, large number of sAuNP-carrying T cells successfully infiltrate into tumor tissues and exert anti-tumor activity to suspend tumor growth, but over time tumor cells evade and regrow. Of note, ≈20% of injected doses of sAuNPs are deposited in tumor tissues, suggesting T cells are an efficient nanoparticle tumor delivery vehicle. When T cells no longer control tumor growth, PTT is performed to further eliminate tumors. In this manner, ACT and PTT are temporally coupled, and the combined immuno-photothermal treatment demonstrated significantly greater therapeutic efficacy than the monotherapy.

Emerging platinum(IV) prodrug nanotherapeutics: A new epoch for platinum-based cancer therapy

Owing to the unique DNA damaging cytotoxicity, platinum (Pt)-based chemotherapy has long been the first-line choice for clinical oncology. Unfortunately, Pt drugs are restricted by the severe dose-dependent toxicity and drug resistance. Correspondingly, Pt(IV) prodrugs are developed with the aim to improve the antitumor performance of Pt drugs. However, as "free" molecules, Pt(IV) prodrugs are still subject to unsatisfactory in vivo destiny and antitumor efficacy. Recently, Pt(IV) prodrug nanotherapeutics, inheriting both the merits of Pt(IV) prodrugs and nanotherapeutics, have emerged and demonstrated the promise to address the underexploited dilemma of Pt-based cancer therapy. Herein, we summarize the latest fronts of emerging Pt(IV) prodrug nanotherapeutics. First, the basic outlines of Pt(IV) prodrug nanotherapeutics are overviewed. Afterwards, how versatile Pt(IV) prodrug nanotherapeutics overcome the multiple biological barriers of antitumor drug delivery is introduced in detail. Moreover, advanced combination therapies based on multimodal Pt(IV) prodrug nanotherapeutics are discussed with special emphasis on the synergistic mechanisms. Finally, prospects and challenges of Pt(IV) prodrug nanotherapeutics for future clinical translation are spotlighted.

Smart Nanoparticle-Based Platforms for Regulating Tumor Microenvironment and Cancer Immunotherapy

Tumor development and metastasis are closely related to the tumor microenvironment (TME). Recently, several studies indicate that modulating TME can enhance cancer immunotherapy. Among various approaches to modulating TME, nanoparticles (NPs) with unique inherent advantages and smart modified characteristics are promising candidates in delivering drugs to cancer cells, amplifying the therapeutic effects, and leading to a cascade of immune responses. In this review, several smart NP-based platforms are briefly introduced, such as responsive NPs, targeting NPs, and the composition of TME, including dendritic cells, macrophages, fibroblasts, endothelial cells, myeloid-derived suppressor cells, and regulatory T cells. Moreover, the recent applications of smart NP-based platforms in regulating TME and cancer immunotherapy are briefly introduced. Last, the advantages and disadvantages of these smart NP-based platforms in potential clinical translation are discussed.

Au nanoparticles decorated nanographene oxide-based platform: Synthesis, functionalization and assessment of photothermal activity

A novel hybrid nanocomposite formed of carboxylated Nano Graphene Oxide (c-NGO), highly densely decorated by monodisperse citrate-coated Au nanoparticles (c-NGO/Au NPs), is synthesized and thoroughly characterized for photothermal applications. A systematic investigation of the role played by the synthetic parameters on the Au NPs decoration of the c-NGO platform is performed, comprehensively studying spectroscopic and morphological characteristics of the achieved nanostructures, thus elucidating their still not univocally explained synthesis mechanism. Remarkably, the Au NPs coating density of the c-NGO sheets is much higher than state-of-the-art systems with analogous composition prepared with different approaches, along with a higher NPs size dispersion. A novel theoretical approach for estimating the average number of NPs per sheet, combining DLS and TEM results, is developed. The assessment of the c-NGO/Au NPs photothermal activity is performed under continuous wave (CW) laser irradiation, at 532 nm and 800 nm, before and after functionalization with PEG-SH. c-NGO/Au NPs composite behaves as efficient photothermal agent, with a light into heat conversion ability higher than that of the single components. The c-NGO/Au NPs compatibility for photothermal therapy is assessed by in vitro cell viability tests, which show no significant effects of c-NGO/Au NPs, as neat and PEGylated, on cell metabolic activity under the investigated conditions. These results demonstrate the great potential held by the prepared hybrid nanocomposite for photothermal conversion technologies, indicating it as particularly promising platform for photothermal ablation of cancer cells.

Recent Advances in Supramolecular-Macrocycle-Based Nanomaterials in Cancer Treatment

Cancer is a severe threat to human life. Recently, various therapeutic strategies, such as chemotherapy, photodynamic therapy, and combination therapy have been extensively applied in cancer treatment. However, the clinical benefits of these therapeutics still need improvement. In recent years, supramolecular chemistry based on host-guest interactions has attracted increasing attention in biomedical applications to address these issues. In this review, we present the properties of the major macrocyclic molecules and the stimulus-response strategies used for the controlled release of therapeutic agents. Finally, the applications of supramolecular-macrocycle-based nanomaterials in cancer therapy are reviewed, and the existing challenges and prospects are discussed.

18F-fluorodeoxyglucose (18F-FDG) Functionalized Gold Nanoparticles (GNPs) for Plasmonic Photothermal Ablation of Cancer: A Review

The meeting and merging between innovative nanotechnological systems, such as nanoparticles, and the persistent need to outperform diagnostic-therapeutic approaches to fighting cancer are revolutionizing the medical research scenario, leading us into the world of nanomedicine. Photothermal therapy (PTT) is a non-invasive thermo-ablative treatment in which cellular hyperthermia is generated through the interaction of near-infrared light with light-to-heat converter entities, such as gold nanoparticles (GNPs). GNPs have great potential to improve recovery time, cure complexity, and time spent on the treatment of specific types of cancer. The development of gold nanostructures for photothermal efficacy and target selectivity ensures effective and deep tissue-penetrating PTT with fewer worries about adverse effects from nonspecific distributions. Regardless of the thriving research recorded in the last decade regarding the multiple biomedical applications of nanoparticles and, in particular, their conjugation with drugs, few works have been completed regarding the possibility of combining GNPs with the cancer-targeted pharmaceutical fluorodeoxyglucose (FDG). This review aims to provide an actual scenario on the application of functionalized GNP-mediated PTT for cancer ablation purposes, regarding the opportunity given by the 18F-fluorodeoxyglucose (18F-FDG) functionalization.

Synergistic chemotherapy and phototherapy based on red blood cell biomimetic nanomaterials

Novel drug delivery systems (DDSs) have become the mainstay of research in targeted cancer therapy. By combining different therapeutic strategies, potential DDSs and synergistic treatment approaches are needed to effectively deal with evolving drug resistance and the adverse effects of cancer. Nowadays, developing and optimizing human cell-based DDSs has become a new research strategy. Among them, red blood cells can be used as DDSs as they significantly enhance the pharmacokinetics of the transported drug cargo. Phototherapy, as a novel adjuvant in cancer treatment, can be divided into photodynamic therapy and photothermal therapy. Phototherapy using erythropoietic nanocarriers to mimic the unique properties of erythrocytes and overcome the limitations of existing DDSs shows excellent prospects in clinical settings. This review provides an overview of the development of photosensitizers and research on bio-nano-delivery systems based on erythrocytes and erythrocyte membranes that are used in achieving synergistic outcomes during phototherapy/chemotherapy.

Smart Modulators Based on Electric Field-Triggering of Surface Plasmon-Polariton for Active Plasmonics

Design and properties of a plasmonic modulator in situ tunable by electric field are presented. Our design comprises the creation of periodic surface pattern on the surface of an elastic polymer supported by a piezo-substrate by excimer laser irradiation and subsequent selective coverage by silver by tilted angle vacuum evaporation. The structure creation was confirmed by AFM and FIB-SEM techniques. An external electric field is used for fine control of the polymer pattern amplitude, which tends to decrease with increasing voltage. As a result, surface plasmon-polariton excitation is quenched, leading to the less pronounced structure of plasmon response. This quenching was checked using UV-Vis spectroscopy and SERS measurements, and confirmed by numerical simulation. All methods prove the proposed functionality of the structures enabling the creation smart plasmonic materials for a very broad range of advanced optical applications.

Mesoporous Silica Materials as an Emerging Tool for Cancer Immunotherapy

Cancer immunotherapy has emerged in the past decade as a promising strategy for treating many forms of cancer by stimulating the patient's immune system. Although immunotherapy has achieved some promising results in clinics, more efforts are required to improve the limitations of current treatments related to lack of effective and targeted cancer antigens delivery to immune cells, dose-limiting toxicity, and immune-mediated adverse effects, among others. In recent years, the use of nanomaterials has proven promising to enhance cancer immunotherapy efficacy and reduce side effects. Among nanomaterials, attention has been recently paid to mesoporous silica nanoparticles (MSNs) as a potential multiplatform for enhancing cancer immunotherapy by considering their unique properties, such as high porosity, and good biocompatibility, facile surface modification, and self-adjuvanticity. This review explores the role of MSN and other nano/micro-materials as an emerging tool to enhance cancer immunotherapy, and it comprehensively summarizes the different immunotherapeutic strategies addressed to date by using MSN.

Biomimetic Keratin-Coated Gold Nanoparticles for Photo-Thermal Therapy in a 3D Bioprinted Glioblastoma Tumor Model

Before entering human clinical studies to evaluate their safety and effectiveness, new drugs and novel medical treatments are subject to extensive animal testing that are expensive and time-consuming. By contrast, advanced technologies enable the development of animal-free models that allow the efficacy of innovative therapies to be studied without sacrificing animals, while providing helpful information and details. We report on the powerful combination of 3D bioprinting (3DB) and photo-thermal therapy (PTT) applications. To this end, we realize a 3DB construct consisting of glioblastoma U87-MG cells in a 3D geometry, incorporating biomimetic keratin-coated gold nanoparticles (Ker-AuNPs) as a photo-thermal agent. The resulting plasmonic 3DB structures exhibit a homogeneous cell distribution throughout the entire volume while promoting the localization of Ker-AuNPs within the cells. A 3D immunofluorescence assay and transmission electron microscopy (TEM) confirm the uniform distribution of fluorescent-labeled Ker-AuNPs in the volume and their capability to enter the cells. Laser-assisted (λ = 532 nm) PTT experiments demonstrate the extraordinary ability of Ker-AuNPs to generate heating, producing the highest temperature rise of about 16 °C in less than 2 min.

NIR-Absorbing Mesoporous Silica-Coated Copper Sulphide Nanostructures for Light-to-Thermal Energy Conversion

Plasmonic nanostructures, featuring near infrared (NIR)-absorption, are rising as efficient nanosystems for in vitro photothermal (PT) studies and in vivo PT treatment of cancer diseases. Among the different materials, new plasmonic nanostructures based on Cu_2−xS nanocrystals (NCs) are emerging as valuable alternatives to Au nanorods, nanostars and nanoshells, largely exploited as NIR absorbing nanoheaters. Even though Cu_2−xS plasmonic properties are not linked to geometry, the role played by their size, shape and surface chemistry is expected to be fundamental for an efficient PT process. Here, Cu_2−xS NCs coated with a hydrophilic mesoporous silica shell (MSS) are synthesized by solution-phase strategies, tuning the core geometry, MSS thickness and texture. Besides their loading capability, the silica shell has been widely reported to provide a more robust plasmonic core protection than organic molecular/polymeric coatings, and improved heat flow from the NC to the environment due to a reduced interfacial thermal resistance and direct electron–phonon coupling through the interface. Systematic structural and morphological analysis of the core-shell nanoparticles and an in-depth thermoplasmonic characterization by using a pump beam 808 nm laser, are carried out. The results suggest that large triangular nanoplates (NPLs) coated by a few tens of nanometers thick MSS, show good photostability under laser light irradiation and provide a temperature increase above 38 °C and a 20% PT efficiency upon short irradiation time (60 s) at 6 W/cm² power density.

Construction of core-in-shell Au@N-HCNs nanozymes for tumor therapy

Noble metals act as nanozymes that can generate reactive oxygen species (ROS) by catalysis to induce apoptosis of tumor cells for cancer therapy. But they are easy to aggregate, which will affect their further application. Carbon materials are often used as the carrier of noble metals to improve their catalytic performance. However, designing a composite structure to build an efficient carbon/noble metal hybrid nanozyme with high catalytic performance for tumor therapy is still a significant challenge. In this work, a core-in-shell structure nanozyme composed of gold nanoparticles (AuNPs) embedded in nitrogen-doped hollow carbon nanoshells (AuNPs@N-HCNs) were fabricated, which exhibited peroxidase-like (POD-like) and oxidase-like (OXD-like) activity. Compared with core-out-of-shell structure composite, the AuNPs@N-HCNs showed a better ability to generate ROS to kill tumor cells. Furthermore, AuNPs@N-HCNs also exhibited satisfactory photothermal conversion properties, which helped build a platform for photothermal therapy. Meanwhile, the enzyme activity produced by AuNPs@N-HCNs increased significantly under light irradiation. Comparing the size of AuNPs in carbon shell, 15 nm AuNPs were better than 2 nm in both enzyme-like activities and in vivo therapeutic effect. In vitro and in vivo studies demonstrated that under the synergistic effect of light-enhancing nanozyme catalysis and photothermal therapy, AuNPs@N-HCNs could induce cancer cell apoptosis and destroy tumors effectively, which provided evidence for the feasibility of tumor catalytic-photothermal treatment.

Transformable vesicles for cancer immunotherapy

Immunotherapy that utilizes the human immune system to fight cancer represents a revolutionary method for cancer treatment. Immunotherapeutic agents that trigger the immune response should be carefully delivered to the desired site to maximize immunotherapy effectiveness and minimize side effects. Vesicles offer the possibility of encapsulating both hydrophilic and hydrophobic drugs and thus serve as a promising delivery tool. As multiple irreconcilable requirements exist at different transport stages, developing vesicles transformable in response to given stimuli is of great significance. In this review, we first introduced various vesicle types used for immunotherapy. Furthermore, the typical stimuli that trigger vesicle transformation and the usually generated transformation styles were described. Focusing on three aspects of antigen-presenting cell (APC)/T cell activation, tumor microenvironment (TME) amelioration, and immunogenic cell death (ICD)-induced immunotherapy, we reviewed recently reported transformable vesicles for tumor treatment. Finally, we put forward possible directions for future research and clinical translation.

Development of next generation nanomedicine-based approaches for the treatment of cancer: we've barely scratched the surface

Interest in nanomedicines has grown rapidly over the past two decades, owing to the promising therapeutic applications they may provide, particularly for the treatment of cancer. Personalised medicine and 'smart' actively targeted nanoparticles represent an opportunity to deliver therapies directly to cancer cells and provide sustained drug release, in turn providing overall lower off-target toxicity and increased therapeutic efficacy. However, the successful translation of nanomedicines from encouraging pre-clinical findings to the clinic has, to date, proven arduous. In this review, we will discuss the use of nanomedicines for the treatment of cancer, with a specific focus on the use of polymeric and lipid nanoparticle delivery systems. In particular, we examine approaches exploring the surface functionalisation of nanomedicines to elicit active targeting and therapeutic effects as well as challenges and future directions for nanoparticles in cancer treatment.

Nanotechnology-Assisted RNA Delivery: From Nucleic Acid Therapeutics to COVID-19 Vaccines

In recent years, the main quest of science has been the pioneering of the groundbreaking biomedical strategies needed for achieving a personalized medicine. Ribonucleic acids (RNAs) are outstanding bioactive macromolecules identified as pivotal actors in regulating a wide range of biochemical pathways. The ability to intimately control the cell fate and tissue activities makes RNA-based drugs the most fascinating family of bioactive agents. However, achieving a widespread application of RNA therapeutics in humans is still a challenging feat, due to both the instability of naked RNA and the presence of biological barriers aimed at hindering the entrance of RNA into cells. Recently, material scientists' enormous efforts have led to the development of various classes of nanostructured carriers customized to overcome these limitations. This work systematically reviews the current advances in developing the next generation of drugs based on nanotechnology-assisted RNA delivery. The features of the most used RNA molecules are presented, together with the development strategies and properties of nanostructured vehicles. Also provided is an in-depth overview of various therapeutic applications of the presented systems, including coronavirus disease vaccines and the newest trends in the field. Lastly, emerging challenges and future perspectives for nanotechnology-mediated RNA therapies are discussed.

Applications of nanomaterials in COVID-19 pandemic

The novel coronavirus 2019 (COVID-19) pandemic represents one of the biggest global health threats in the last two decades, so researchers around the world are searching for solutions and treatments for COVID-19. At the time of writing, there are no specific drugs that have demonstrated suitable effectiveness in treating COVID-19. The current challenge involves designing tools for the prevention, rapid and accurate diagnosis, drug delivery, and effective treatment of this novel coronavirus. In this short review, we discuss how nanotechnology offers new ways to combat COVID-19, and how nanomaterials can be applied to control the COVID-19 outbreak. We also summarize relevant studies regarding the use of nanomaterials for preventing viral spread, preparing vaccines, and diagnosing coronavirus, as well as studies that show how nanoparticles can be used as drug delivery systems for the treatment of viral infections. Research on nanotechnology-based diagnosis, drug delivery, and antiviral therapy is currently in the early stages. However, the unique chemical properties of some nanomaterials highlight the broad prospect of nanomaterials in the future, and we propose that they will play an important role in the fight against COVID-19.

GRAPHICAL ABSTRACT

Personalized Reusable Face Masks with Smart Nano-Assisted Destruction of Pathogens for COVID-19: A Visionary Road

The Coronavirus disease 2019 (COVID-19) emergency has demonstrated that the utilization of face masks plays a critical role in limiting the outbreak. Healthcare professionals utilize masks all day long without replacing them very frequently, thus representing a source of cross-infection for patients and themselves. Nanotechnology is a powerful tool with the capability to produce nanomaterials with unique physicochemical and antipathogen properties. Here, how to realize non-disposable and highly comfortable respirators with light-triggered self-disinfection ability by bridging bioactive nanofiber properties and stimuli-responsive nanomaterials is outlined. The visionary road highlighted in this Concept is based on the possibility of developing a new generation of masks based on multifunctional membranes where the presence of nanoclusters and plasmonic nanoparticles arranged in a hierarchical structure enables the realization of a chemically driven and on-demand antipathogen activities. Multilayer electrospun membranes have the ability to dissipate humidity present within the mask, enhancing the wearability and usability. The photothermal disinfected membrane is the core of these 3D printed and reusable masks with moisture pump capability. Personalized face masks with smart nano-assisted destruction of pathogens will bring enormous advantages to the entire global community, especially for front-line personnel, and will open up great opportunities for innovative medical applications.

Smart Nanomaterials for Biomedical Applications-A Review

Recent advances in nanotechnology have forced the obtaining of new materials with multiple functionalities. Due to their reduced dimensions, nanomaterials exhibit outstanding physio-chemical functionalities: increased absorption and reactivity, higher surface area, molar extinction coefficients, tunable plasmonic properties, quantum effects, and magnetic and photo properties. However, in the biomedical field, it is still difficult to use tools made of nanomaterials for better therapeutics due to their limitations (including non-biocompatible, poor photostabilities, low targeting capacity, rapid renal clearance, side effects on other organs, insufficient cellular uptake, and small blood retention), so other types with controlled abilities must be developed, called "smart" nanomaterials. In this context, the modern scientific community developed a kind of nanomaterial which undergoes large reversible changes in its physical, chemical, or biological properties as a consequence of small environmental variations. This systematic mini-review is intended to provide an overview of the newest research on nanosized materials responding to various stimuli, including their up-to-date application in the biomedical field.

Biomimetic keratin gold nanoparticle-mediated in vitro photothermal therapy on glioblastoma multiforme

Aim: To realize and characterize a new generation of keratin-coated gold nanoparticles (Ker-AuNPs) as highly efficient photosensitive nanosized therapeutics for plasmonic photothermal (PPT) therapy. Materials & methods: The chemical, physical, morphological and photothermal properties of Ker-AuNPs are investigated using dynamic light scattering, ζ-potential, UV-Visible, Fourier transform infrared spectroscopy, x-ray photoelectron spectroscopy, transmission electron microscopy and high-resolution thermography. In vitro experiments are performed on a human glioblastoma cell line (i.e., U87-MG), using viability assays, transmission electron microscopy, fluorescence microscopy, cytometric analyses and PPT experiments. Results: Experiments confirm the excellent biocompatibility of Ker-AuNPs, their efficient cellular uptake and localized photothermal heating capabilities. Conclusion: The reported structural and functional properties pointed out these Ker-AuNPs as a promising new tool in the field of biocompatible photothermal agents for PPT treatments against cancer-related diseases.

A PEGylated alternating copolymeric prodrug of sulfur dioxide with glutathione responsiveness for Irinotecan delivery

An enhanced anticancer strategy combining the chemotherapy from Irinotecan with the oxidative damage from a sulfur dioxide polymer prodrug is presented.

Multifunctional Platform Based on Electrospun Nanofibers and Plasmonic Hydrogel: A Smart Nanostructured Pillow for Near-Infrared Light-Driven Biomedical Applications

Multifunctional nanomaterials with the ability to respond to near-infrared (NIR) light stimulation are vital for the development of highly efficient biomedical nanoplatforms with a polytherapeutic approach. Inspired by the mesoglea structure of jellyfish bells, a biomimetic multifunctional nanostructured pillow with fast photothermal responsiveness for NIR light-controlled on-demand drug delivery is developed. We fabricate a nanoplatform with several hierarchical levels designed to generate a series of controlled, rapid, and reversible cascade-like structural changes upon NIR light irradiation. The mechanical contraction of the nanostructured platform, resulting from the increase of temperature to 42 °C due to plasmonic hydrogel-light interaction, causes a rapid expulsion of water from the inner structure, passing through an electrospun membrane anchored onto the hydrogel core. The mutual effects of the rise in temperature and water flow stimulate the release of molecules from the nanofibers. To expand the potential applications of the biomimetic platform, the photothermal responsiveness to reach the typical temperature level for performing photothermal therapy (PTT) is designed. The on-demand drug model penetration into pig tissue demonstrates the efficiency of the nanostructured platform in the rapid and controlled release of molecules, while the high biocompatibility confirms the pillow potential for biomedical applications based on the NIR light-driven multitherapy strategy.

Synthesis of Carboxy-Dimethylmaleic Amide Linked Polymer Conjugate Based Ultra-pH-sensitive Nanoparticles for Enhanced Antitumor Immunotherapy

Cytotoxic T lymphocytes (CTLs) are an important tool for anticancer immunotherapy. To elicit powerful CTL activities, ultra-pH-sensitive nanoparticles (NPs) based on methoxy poly(ethylene glycol)-b-[poly(diisopropylamino)ethyl methacrylate] have been synthesized as a vaccine delivery platform. A representative CTL epitope, ovalbumin (OVA) peptide antigen, was covalently conjugated to the polymer backbone through an acid responsive carboxy-dimethylmaleic amide linker (CDM) resulting in polymer P-CDM-OVA. Interestingly, while the P-CDM-OVA released OVA peptide slowly in a pH 6.4 buffer, the addition of bovine serum albumin (BSA) mimicking proteins encountered in a cellular and/or in vivo environment significantly accelerated the release process. Successful cell surface presentation of OVA was observed when P-CDM-OVA based ultra-pH-sensitive particles were incubated with antigen presenting cells. These P-CDM-OVA NPs greatly enhanced CTL responses in vivo compared to the free peptide or the previously reported acetalated dextran particles encapsulating OVA. The P-CDM was also investigated for adjuvant conjugation, and the coadministration of P-CDM-OVA and the P-CDM-adjuvant conjugate NPs further improved CTL responses in vivo and effectively reduced tumor growth in mice. Thus, the CDM linked polymer presents a promising platform for anticancer immunotherapy.

ICG-loaded gold nano-bipyramids with NIR activatable dual PTT-PDT therapeutic potential in melanoma cells

A great amount of effort is directed towards the progress of cancer treatment approaches aspiring to develop non-invasive, targeted and highly efficient therapies. In this context, Photothermal (PTT) and Photodynamic (PDT) Therapies were proven as promising. This work aims to integrate the therapeutic activities of two near-infrared (NIR) photoactive biomaterials - gold nano-bipyramids (AuBPs) and Indocyanine Green (ICG) - into one single targeted hybrid nanosystem able to operate as dual PTT-PDT agent with higher efficiency compared with each one alone. Firstly, different aspect ratio' AuBPs were systematically investigated in water solution for their intrinsic ability to efficiently generate toxic reactive oxygen species, namely oxygen singlet (¹O₂), under NIR laser irradiation, as this effect is less investigated in literature. Interestingly, the photodynamic activity of AuBPs measured by monitoring the photooxidation of 9,10-Anthracenediyl-bis(methylene)dimalonic acid (ABDA) - a well-known ¹O₂ sensor, is important, counting for 30 % decrease in ABDA optical absorbance for the most active AuBPs, well-correlating with the previously determined photothermal conversion efficiency. Furthermore, ICG was successfully grafted onto the Poly-lactic acid (PLA) coating of plasmonic nanoparticles and, consequently, the as-designed fully integrated hybrid nanosystem shows improved PTT-PDT performance in solution. Specifically, by triggering simultaneous PTT-PDT activities, the ¹O₂ amount is doubled, while the heating monitoring shows higher and faster increase in temperature compared to AuBPs alone. Finally, the efficiency of the combined PTT-PDT therapeutic activity was validated in vitro against B16-F10 cell line by covalent conjugation of the nanosystem with Folic Acid, which ensures the cellular recognition by overexpression of folate receptor.

Nanomaterials for the Photothermal Killing of Bacteria

An upsurge in the multidrug-resistant (MDR) bacterial pestilence is a global cause for concern in terms of human health. Lately, nanomaterials with photothermal effects have assisted in the efficient killing of MDR bacteria, attributable to their uncommon plasmonic, photocatalytic, and structural properties. Examinations of substantial amounts of photothermally enabled nanomaterials have shown bactericidal effects in an optimized time under near-infrared (NIR) light irradiation. In this review, we have compiled recent advances in photothermally enabled nanomaterials for antibacterial activities and their mechanisms. Photothermally enabled nanomaterials are classified into three groups, including metal-, carbon-, and polymer-based nanomaterials. Based on substantial accomplishments with photothermally enabled nanomaterials, we have inferred current trends and their prospective clinical applications.