NIR Light-Degradable Antimony Nanoparticle-Based Drug-Delivery Nanosystem for Synergistic Chemo-Photothermal Therapy in Vitro

Poly(Glutamic Acid)-Engineered Nanoplatforms for Enhanced Cancer Phototherapy

Phototherapies, including photothermal therapy and photodynamic therapy, have gained booming development over the past several decades for their attractive non-invasiveness nature, negligible adverse effects, minimal systemic toxicity, and high spatial selectivity. Phototherapy usually requires three components: light irradiation, photosensitizers, and molecular oxygen. Photosensitizers can convert light energy into heat or reactive oxygen species, which can be used in the tumor-killing process. The direct application of photosensitizers in tumor therapy is restricted by their poor water solubility, fast clearance, severe toxicity, and low cellular uptake. The encapsulation of photosensitizers into nanostructures is an attractive strategy to overcome these critical limitations. Poly(glutamic acid) (PGA) is a kind of poly(amino acid)s containing the repeating units of glutamic acid. PGA has superiority for cancer treatment because of its good biocompatibility, low immunogenicity, and modulated pH responsiveness. The hydrophilicity nature of PGA allows the physical entrapment of photosensitizers and anticancer drugs via the construction of amphiphilic polymers. Moreover, the pendent carboxyl groups of PGA enable chemical conjugation with therapeutic agents. In this mini-review, we highlight the stateof- the-art design and fabrication of PGA-based nanoplatforms for phototherapy. We also discuss the potential challenges and future perspectives of phototherapy, and clinical translation of PGA-based nanomedicines.

Photothermal Nanomaterials: A Powerful Light-to-Heat Converter

All forms of energy follow the law of conservation of energy, by which they can be neither created nor destroyed. Light-to-heat conversion as a traditional yet constantly evolving means of converting light into thermal energy has been of enduring appeal to researchers and the public. With the continuous development of advanced nanotechnologies, a variety of photothermal nanomaterials have been endowed with excellent light harvesting and photothermal conversion capabilities for exploring fascinating and prospective applications. Herein we review the latest progresses on photothermal nanomaterials, with a focus on their underlying mechanisms as powerful light-to-heat converters. We present an extensive catalogue of nanostructured photothermal materials, including metallic/semiconductor structures, carbon materials, organic polymers, and two-dimensional materials. The proper material selection and rational structural design for improving the photothermal performance are then discussed. We also provide a representative overview of the latest techniques for probing photothermally generated heat at the nanoscale. We finally review the recent significant developments of photothermal applications and give a brief outlook on the current challenges and future directions of photothermal nanomaterials.

Chemistry of two-dimensional pnictogens: emerging post-graphene materials for advanced applications

The layered allotropes of group 15 (P, As, Sb and Bi), also called two-dimensional (2D) pnictogens, have emerged as one of the most promising families of post-graphene 2D-materials. This is mainly due to the great variety of properties they exhibit, including layer-dependent bandgap, high charge-carrier mobility and current on/off ratios, strong spin-orbit coupling, wide allotropic diversity and pronounced chemical reactivity. These are key ingredients for exciting applications in (opto)electronics, heterogeneous catalysis, nanomedicine or energy storage and conversion, to name a few. However, there are still many challenges to overcome in order to fully understand their properties and bring them to real applications. As a matter of fact, due to their strong interlayer interactions, the mechanical exfoliation (top-down) of heavy pnictogens (Sb & Bi) is unsatisfactory, requiring the development of new methodologies for the isolation of single layers and the scalable production of high-quality flakes. Moreover, due to their pronounced chemical reactivity, it is necessary to develop passivation strategies, thus preventing environmental degradation, as in the case of bP, or controlling surface oxidation, with the corresponding modification of the interfacial and electronic properties. In this Feature Article we will discuss, among others, the most important contributions carried out in our group, including new liquid phase exfoliation (LPE) processes, bottom-up colloidal approaches, the preparation of intercalation compounds, innovative non-covalent and covalent functionalization protocols or novel concepts for potential applications in catalysis, electronics, photonics, biomedicine or energy storage and conversion. The past years have seen the birth of the chemistry of pnictogens at the nanoscale, and this review intends to highlight the importance of the chemical approach in the successful development of routes to synthesise, passivate, modify, or process these materials, paving the way for their use in applications of great societal impact.

Inorganic Nanomaterials Used in Anti-Cancer Therapies:Further Developments

In this article, we provide an overview of the progress of scientists working to improve the quality of life of cancer patients. Among the known methods, cancer treatment methods focusing on the synergistic action of nanoparticles and nanocomposites have been proposed and described. The application of composite systems will allow precise delivery of therapeutic agents to cancer cells without systemic toxicity. The nanosystems described could be used as a high-efficiency photothermal therapy system by exploiting the properties of the individual nanoparticle components, including their magnetic, photothermal, complex, and bioactive properties. By combining the advantages of the individual components, it is possible to obtain a product that would be effective in cancer treatment. The use of nanomaterials to produce both drug carriers and those active substances with a direct anti-cancer effect has been extensively discussed. In this section, attention is paid to metallic nanoparticles, metal oxides, magnetic nanoparticles, and others. The use of complex compounds in biomedicine is also described. A group of compounds showing significant potential in anti-cancer therapies are natural compounds, which have also been discussed.

Thermosensitive TMPO-oxidized lignocellulose/cationic agarose hydrogel loaded with deferasirox nanoparticles for photothermal therapy in melanoma

Deferasirox (DFX) is an iron-chelating agent effective in treating various kinds of cancers, which inhibits iron metabolism in cancer cells. The recent study aimed to prepare an injectable thermosensitive hydrogel based on lignocellulose and agarose containing deferasirox-loaded polypyrrole nanoparticles for local drug delivery in a combined chemo-photothermal therapy by laser light irradiation. Polypyrrole nanoparticles containing DFX were made by the emulsification method and optimized. Thermosensitive hydrogels were prepared by quaternary ammonium substituted agarose and TMPO-oxidized lignocellulose at different ratios, and the optimal hydrogel was selected based on gelation time, gelation temperature, and injectability. DFX- loaded polypyrrole nanoparticles were then added to the hydrogel, and the drug release, rheology test, injectability, degradation, and swelling percent, as well as cytotoxicity, and photothermal properties, were studied on B16F10, human melanoma cells. The hydrogel with 2 % anionic lignocellulose and 0.5 % cationic agarose showed the shortest gelation time and the highest mechanical strength. It transferred from a liquid state at 4 °C into a semisolid form at 37 °C with a gelation time of 10.3 min. The nanoparticles loaded in hydrogel showed dose-dependent cytotoxicity. The cytotoxic dose of the drug was reduced by laser light irradiation.

Polydopamine-Coated Cu-BTC Nanowires for Effective Magnetic Resonance Imaging and Photothermal Therapy

Herein, we present a one-pot hydrothermal approach for synthesizing metal–organic framework-derived copper (II) benzene-1,3,5-tricarboxylate (Cu-BTC) nanowires (NWs) using dopamine as the reducing agent and precursor for a polydopamine (PDA) surface coating formation. In addition, PDA can act as a PTT agent and enhance NIR absorption, producing photothermal effects on cancer cells. These NWs displayed a photothermal conversion efficiency of 13.32% after PDA coating and exhibited good photothermal stability. Moreover, NWs with a suitable T1 relaxivity coefficient (r1 = 3.01 mg−1 s−1) can be effectively used as magnetic resonance imaging (MRI) contrast agents. By increasing concentrations, cellular uptake studies showed a greater uptake of Cu-BTC@PDA NWs into cancer cells. Further, in vitro studies showed PDA-coated Cu-BTC NWs possess exceptional therapeutic performance by 808 nm laser irradiation, destroying 58% of cancer cells compared with the absence of laser irradiation. This promising performance is anticipated to advance the research and implementation of copper-based NWs as theranostic agents for cancer treatment.

Effect of Cuprous Oxide Nanocubes and Antimony Nanorods on the Performance of Silicon Nanowire-Based Quasi-Solid-State Solar Cell

Antimony nanorods (SbNRs) anchored to vertically aligned SiNWs serve as cosensitizers and enhance the light absorption of NWs, and their favorably positioned valence band (VB) coupled with their p-type semiconducting nature allows fast hole extraction from SiNWs. Photocorrosion of SiNWs is effectively prevented by a monolayer of N-[3-(trimethoxysilyl)propyl]aniline (TMSPA). Upon assembling a quasi-solid-state solar cell with a SbNRs@TMSPA@SiNW photoanode, a triiodide-iodide (I₃ ^-/I^-) redox couple-based gel encompassing dispersed p-type cuprous oxide nanocubes (Cu₂O NCs) as the hole transport material. and an electrocatalytic NiO as the counter electrode, a power conversion efficiency (PCE) of 4.7% (under 1 sun) is achieved, which is greater by 177% relative to an analogous cell devoid of the Cu₂O NCs and SbNRs. SbNRs at the photoanode maximize charge separation and suppress electron-hole and electron-I₃ ^- recombination at the photoanode/electrolyte interface, thereby improving the overall current collection efficiency. Concurrently, the Cu₂O NCs facilitate hole scavenging from SbNRs or SiNWs and relay them rapidly to the I^- ions in the electrolyte. Optically transparent and mesoporous NiO with a VB conducive to accepting electrons from FTO permits abundant interaction with I₃ ^- ions. The high PCE is a cumulative outcome of the synergistic attributes of SbNRs, Cu₂O NCs, and NiO. The SbNRs@TMSPA@SiNWs/Cu₂O-gel/NiO solar cell also exhibits a noteworthy operational stability, for it endures 500 h of continuous 1 sun illumination accompanied by an ∼24.4% drop in its PCE. The solar cell architecture in view of the judiciously chosen components with favorable energy level offsets, semiconducting/photoactive properties, and remarkable stability opens up pathways to adapt these materials to other solar cells as well.

Nanomedicine and versatile therapies for cancer treatment

The higher prevalence of cancer is related to high rates of mortality and morbidity worldwide. By virtue of the properties of matter at the nanoscale, nanomedicine is proven to be a powerful tool to develop innovative drug carriers with greater efficacies and fewer side effects than conventional therapies. In this review, different nanocarriers for controlled drug release and their routes of administration have been discussed in detail, especially for cancer treatment. Special emphasis has been given on the design of drug delivery vehicles for sustained release and specific application methods for targeted delivery to the affected areas. Different polymeric vehicles designed for the delivery of chemotherapeutics have been discussed, including graft copolymers, liposomes, hydrogels, dendrimers, micelles, and nanoparticles. Furthermore, the effect of dimensional properties on chemotherapy is vividly described. Another integral section of the review focuses on the modes of administration of nanomedicines and emerging therapies, such as photothermal, photodynamic, immunotherapy, chemodynamic, and gas therapy, for cancer treatment. The properties, therapeutic value, advantages, and limitations of these nanomedicines are highlighted, with a focus on their increased performance versus conventional molecular anticancer therapies.

Degradable mesoporous semimetal antimony nanospheres for near-infrared II multimodal theranostics

Metallic and semimetallic mesoporous frameworks are of great importance owing to their unique properties and broad applications. However, semimetallic mesoporous structures cannot be obtained by the traditional template-mediated strategies due to the inevitable hydrolytic reaction of semimetal compounds. Therefore, it is yet challenging to fabricate mesoporous semimetal nanostructures, not even mention controlling their pore sizes. Here we develop a facile and robust selective etching route to synthesize monodispersed mesoporous antimony nanospheres (MSbNSs). The pore sizes of MSbNSs are tunable by carefully controlling the partial oxidation of Sb nuclei and the selective etching of the as-formed Sb₂O₃. MSbNSs show a wide absorption from visible to second near-infrared (NIR-II) region. Moreover, PEGylated MSbNSs are degradable and the degradation mechanism is further explained. The NIR-II photothermal performance of MSbNSs is promising with a high photothermal conversion efficiency of ~44% and intensive NIR-II photoacoustic signal. MSbNSs show potential as multifunctional nanomedicines for NIR-II photoacoustic imaging guided synergistic photothermal/chemo therapy in vivo. Our selective etching process would contribute to the development of various semimetallic mesoporous structures and efficient multimodal nanoplatforms for theranostics.

Ultra-small bimetallic phosphide for dual-modal MRI imaging guided photothermal ablation of tumor

Metal phosphides have been proved to be the potential theranostic agents of tumor. However, the limitation of single-modal imaging or treatment effect of such materials need to be further improved....

Photodynamic and Photothermal Therapy of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the most common primary liver tumor. It is ranked the sixth most common neoplasm and the third most common cause of cancer mortality. At present, the most common treatment for HCC is surgery, but the 5-year recurrence rates are still high. Patients with early stage HCC with few nodules can be treated with resection or radiofrequency ablation (RFA); while for multinodular HCC, transarterial chemoembolization (TACE) has been the first-line treatment. In recent years, based on medical engineering cooperation, nanotechnology has been increasingly applied to the treatment of cancer. Photodynamic therapy and photothermal therapy are effective for cancer. This paper summarizes the latest progress of photodynamic therapy and photothermal therapy for HCC, with the aim of providing new ideas for the treatment of HCC.

Enhanced Photothermal Performance by Carbon Dot-Chelated Polydopamine Nanoparticles

Polydopamine (PDA) has been widely used in biomedical applications including imaging contrast agents, antioxidants, UV protection, and photothermal therapy due to its biocompatibility, metal-ion chelation, free-radical scavenging, and wideband absorption, but its low photothermal efficiency still needs to be improved. In this study, we chelated near-infrared (NIR) sensitive carbon quantum dots on the surface of polydopamine (PDA-PEI@N,S-CQDs) to increase its near-infrared absorption. Surprisingly, although only 4% (w/w) of carbon quantum dots was conjugated on the PDA surface, it still increased the photothermal efficiency by 30%. Moreover, PDA-PEI@N,S-CQDs could also be used as the drug carrier for loading 60% (w/w) of the DOX and achieved stimuli-responsive drug release under lysosomal pH (pH 5.0) and 808 nm laser illumination. For in vitro therapeutic experiment, PDA-PEI@N,S-CQDs showed the remarkable therapeutic performance under 808 nm laser irradiation for killing 90% of cancer cells compared with 50% by pure PDA nanoparticles, and the efficacy was even higher after loading DOX owing to the synergistic effect by photothermal therapy and chemotherapy. This intelligent and effective therapeutic nanosystem based on PDA-PEI@N,S-CQDs showed enhanced photothermal behavior after chelating carbon dots and promoted the future development of a nanoplatform for stimuli-responsive photothermal/chemo therapy.

Selenium Vacancy Engineering Using Bi2Se3 Nanodots for Boosting Highly Efficient Photonic Hyperthermia

Despite bismuth-based energy conversion nanomaterials having attracted extensive attention for nanomedicine, the nanomaterials suffer from major shortcomings including low tumor accumulation, long internal retention time, and undesirable photothermal conversion efficiency (PCE). To combat these challenges, bovine serum albumin and folic acid co-modified Bi2Se3 nanomedicine with rich selenium vacancies (abbreviated as VSe-BS) was fabricated for the second near-infrared (NIR-II) light-triggered photonic hyperthermia. More importantly, selenium vacancies on the crystal planes (0 1 5) and (0 1 11) of VSe-BS with similar formation energies could be distinctively observed via aberration-corrected scanning transmission electron microscopy images. The defect engineering endows VSe-BS with enhanced conductivity, making VSe-BS possess outstanding PCE (54.1%) in the NIR-II biowindow and desirable photoacoustic imaging performance. Tumor ablation studies indicate that VSe-BS possesses satisfactory therapeutic outcomes triggered by NIR-II light. These findings give rise to inspiration for further broadening the biological applications of defect engineering bismuth-based nanomaterials.

Real-Time Temperature Monitoring of Photoinduced Cargo Release inside Living Cells Using Hybrid Capsules Decorated with Gold Nanoparticles and Fluorescent Nanodiamonds

Real-time temperature monitoring within biological objects is a key fundamental issue for understanding the heating process and performing remote-controlled release of bioactive compounds upon laser irradiation. The lack of accurate thermal control significantly limits the translation of optical laser techniques into nanomedicine. Here, we design and develop hybrid (complex) carriers based on multilayered capsules combined with nanodiamonds (NV centers) as nanothermometers and gold nanoparticles (Au NPs) as nanoheaters to estimate an effective laser-induced temperature rise required for capsule rupture and further release of cargo molecules outside and inside cancerous (B16-F10) cells. We integrate both elements (NV centers and Au NPs) in the capsule structure using two strategies: (i) loading inside the capsule's cavity (CORE) and incorporating them inside the capsule's wall (WALL). Theoretically and experimentally, we show the highest and lowest heat release from capsule samples (CORE or WALL) under laser irradiation depending on the Au NP arrangement within the capsule. Applying NV centers, we measure the local temperature of capsule rupture inside and outside the cells, which is determined to be 128 ± 1.12 °C. Finally, the developed hybrid containers can be used to perform the photoinduced release of cargo molecules with simultaneous real-time temperature monitoring inside the cells.

Inorganic nanomaterials with rapid clearance for biomedical applications

Inorganic nanomaterials that have inherently exceptional physicochemical properties (e.g., catalytic, optical, thermal, electrical, or magnetic performance) that can provide desirable functionality (e.g., drug delivery, diagnostics, imaging, or therapy) have considerable potential for application in the field of biomedicine. However, toxicity can be caused by the long-term, non-specific accumulation of these inorganic nanomaterials in healthy tissues, preventing their large-scale clinical utilization. Over the past several decades, the emergence of biodegradable and clearable inorganic nanomaterials has offered the potential to prevent such long-term toxicity. In addition, a comprehensive understanding of the design of such nanomaterials and their metabolic pathways within the body is essential for enabling the expansion of theranostic applications for various diseases and advancing clinical trials. Thus, it is of critical importance to develop biodegradable and clearable inorganic nanomaterials for biomedical applications. This review systematically summarizes the recent progress of biodegradable and clearable inorganic nanomaterials, particularly for application in cancer theranostics and other disease therapies. The future prospects and opportunities in this rapidly growing biomedical field are also discussed. We believe that this timely and comprehensive review will stimulate and guide additional in-depth studies in the area of inorganic nanomedicine, as rapid in vivo clearance and degradation is likely to be a prerequisite for the future clinical translation of inorganic nanomaterials with unique properties and functionality.

Near-Infrared-Light-Responsive Copper Oxide Nanoparticles as Efficient Theranostic Nanoagents for Photothermal Tumor Ablation

A theranostic nanoagent exhibits great promise to improve diagnostic accuracy and therapy efficacy. Herein, a kind of theranostic nanoagent based on poly(vinylpyrrolidone) (PVP)-protected ultrasmall Cu_1.2O nanoparticles (Cu_1.2O NPs) is developed by a facile liquid reduction method. Attributed to high near-infrared absorbance and good biocompatibility, Cu_1.2O NPs have shown significant potential for photothermal therapy. Moreover, Cu_1.2O NPs with a satisfactory T₁ relaxivity coefficient (r₁) can be well applied as outstanding MRI contrast agents and exhibit excellent magnetic resonance imaging (MRI) ability. In vivo treatments further demonstrate that Cu_1.2O NPs could be well used as multifunctional theranostic nanoagents, which achieve precise MRI and a high photothermal antitumor effect. It is expected to further promote the research and application of copper-based nanoparticles as theranostic nanoagents for cancer therapy.

Antimony Nanopolyhedrons with Tunable Localized Surface Plasmon Resonances for Highly Effective Photoacoustic-Imaging-Guided Synergistic Photothermal/Immunotherapy

Antimony (Sb), a typical group VA semimetal, has rarely been studied both experimentally and theoretically in plasmonic photothermal therapy, possibly due to the lack of effective morphology-controllable methods for the preparation of high-quality Sb nanocrystals. In this study, an effective ligand-guided growth strategy to controllably synthesize Sb nanopolyhedrons (Sb NPHs) with ultrahigh photothermal conversion efficiency (PTCE), good photothermal stability, as well as biocompatibility is presented. Furthermore, the modulation effect of different morphologies on localized surface plasmon resonance (LSPR) of Sb NPHs in experimentation is successfully observed. When the resonance frequency of the Sb NPHs is matched well with the excitation wavelength (808 nm), the PTCE of the Sb NPHs is as high as 62.1%, which is noticeably higher compared to most of the reported photothermal agents. The Sb NPHs also exhibit good photothermal stability. In addition, Sb-NPHs-based multifunctional nanomedicines are further constructed via loading 1-methyl-d-tryptophan on PEGylated Sb NPHs for a highly efficient photoacoustic-imaging-guided synergistic photothermal/immune-therapy of tumors in vivo. This work can stimulate further theoretical and experimental investigations of Sb NPHs and other semimetal nanomaterials regarding their LSPR properties and inspire various potential applications of semimetals in biomedicine and sensors.

Clearable Nanoparticles for Cancer Photothermal Therapy

Nanoparticles are important mediators for cancer photothermal therapy (PTT) where they can efficiently convert photon energy into heat and ablate the surrounding cancer cells with superior spatial and temporal precision. Recent decades have witnessed a booming development of numerous formulations of PTT nanoparticles that exhibit outstanding anti-tumor efficacy in preclinical studies. However, their clinical translation has been mined by safety concerns, especially their long-term impact on human body. Biodegradable nanoparticles that can be excreted after PTT, therefore, are gaining popularity due to their biocompatibility and improved safety profiles. This chapter provides an update on the progress in clearable PTT nanoparticles for cancer treatment. We discuss their design, synthesis strategy, and physicochemical properties relevant to photothermal performance. We also review their biodistribution patterns and in vivo anti-tumor efficacy, along with their degradation mechanism and clearance kinetics. Lastly, we present a brief overview of the imaging techniques to noninvasively monitor the degradation of PTT nanoparticles.

Solutions to the Drawbacks of Photothermal and Photodynamic Cancer Therapy

Phototherapy such as photothermal therapy and photodynamic therapy in cancer treatment has been developed quickly over the past few years for its noninvasive nature and high efficiency. However, there are still many drawbacks in phototherapy that prevent it from clinical applications. Thus, scientists have designed different systems to overcome the issues associated with phototherapy, including enhancing the targeting ability of phototherapy, low-temperature photothermal therapy, replacing near-infrared light with other excitation sources, and so on. This article discusses the problems and shortcomings encountered in the development of phototherapy and highlights possible solutions to address them so that phototherapy may become a useful cancer treatment approach in clinical practice. This article aims to give a brief summary about current research advancements in phototherapy research and provides a quick guideline toward future developments in the field.

Colloidal chemical bottom-up synthesis routes of pnictogen (As, Sb, Bi) nanostructures with tailored properties and applications: a summary of the state of the art and main insights

Adjusting the colloidal chemistry synthetic parameters for pnictogen nanostructures leads to a fine control of their physical properties and the resulting performance in applications. Image adapted from Slidesgo.com.

Co-drug delivery of regorafenib and cisplatin with amphiphilic copolymer nanoparticles: enhanced in vivo antitumor cancer therapy in nursing care

Cancers continue to be the second leading cause of death worldwide. Despite the development and improvement of surgery, chemotherapy and radiotherapy in cancer management, effective tumor ablation strategies are still in need due to high cancer patient mortality. Hence, we have established a new approach to achieve treatment-actuated modifications in a tumor microenvironment by using synergistic activity between two potential anticancer drugs. Dual drug delivery of Regorafenib (REGO) and Cisplatin (PT) exhibits a great anticancer potential, as REGO enhances the effect of PT treatment of human cells by providing stability of the microenvironment. However, encapsulation of REGO and PT fanatical by methoxypoly(ethylene glycol)-block-poly(D, L-lactic acid) (PEG-PLA in termed as NPs) is incompetent owing to unsuitability between the binary Free REGO and PT core and the polymeric system. Now, we display that PT can be prepared by hydrophobic coating of the dual drug centers with dioleoylphosphatidic acid (DOPA). The DOPA-covered PT can be co-encapsulated in PLGA NPs alongside REGO to stimulate excellent anticancer property. The occurrence of the PT suggestively enhanced the encapsulations of REGO into PLGA NPs (REGO-PT NPs). Further, the morphology of REGO NPs, PT NPs, and REGO-PT NPs and nanoparticle size was examined by transmission microscopy (TEM), respectively. Furthermore REGO-PT NPs induced significant apoptosis in human lung A549 and ovarian A2780 cancer cells by in vitro. The morphological observation and apoptosis were confirmed by the various biochemical assayes (AO-EB, Nuclear Staining and Annexin V-FITC). In a xenograft model of lung cancer, this nanotherapy shows a durable inhibition of tumor progression upon the administration of a tolerable dose. Our results suggest that a hydrophobic and highly toxic drug can be rationally converted into a pharmacologically efficient and self-deliverable nursing care of nanotherapy. Highlights Dual drug delivery of Regorafenib (REGO) and Cisplatin (PT) exhibits a great anticancer potential, as REGO enhances the effect of PT treatment of human cells by providing stability of the microenvironment. REGO-PT NPs induced significant apoptosis in human lung A549 and ovarian A2780 cancer cells by in vitro. The morphological observation and apoptosis were confirmed by the various biochemical assayes. In a xenograft model of lung cancer, this nanotherapy shows a durable inhibition of tumor progression upon the administration of a tolerable dose.

A thieno-isoindigo derivative-based conjugated polymer nanoparticle for photothermal therapy in the NIR-II bio-window

Photothermal therapy (PTT), a powerful tool for non-invasive cancer treatment, has been recognized as an alternative strategy for cancer therapy in the clinic, and it is promoted by optical absorbing agents (photothermal agents) that can intensively convert near-infrared (NIR) light into thermal energy for cancer ablation. Conjugated polymer nanoparticles (CPNs) have recently attracted extensive attention owing to their excellent photothermal properties. However, the absorption of typical CPNs is mostly located in the traditional near-infrared region (NIR-I, 700-900 nm), which suffers from low tissue penetration, so the penetration depth is still limited and severely restricts their further applications. Compared with the NIR-I light, the second near-infrared window light (NIR-II, 1000-1700 nm) could efficiently enhance the tissue penetration depth, however, CPNs which absorb NIR-II region light are still especially limited and need further exploration. Here, a thieno-isoindigo derivative-based Donor-Acceptor (D-A) polymer (BTPBFDTS), which exhibited excellent absorption characteristics from the NIR-I to NIR-II window, was prepared. After formation of nanoparticles and surface functionalization, the prepared nanoparticles (NPsBTPBFDTS@HA NPs) exhibited obvious targeting ability, high photothermal conversion efficiency and photoacoustic imaging effects under 1064 nm irradiation. Both in vitro and in vivo studies demonstrate that our obtained NPsBTPBFDTS@HA nanoparticles possess excellent PTT efficacy including extremely high cancer cell killing ability and admirable tumor elimination efficiency. Hence, this work developed a promising photothermal conversion agent based on CPNs for cancer ablation.

Dandelion-Inspired Hierarchical Upconversion Nanoplatform for Synergistic Chemo-Photodynamic Therapy In Vitro

Herein, inspired by the structure of a dandelion, we develop a fresh preparation of an upconversion nanoplatform (UCNPs@C₆₀-DOX-FA). The target part folic acid (FA) modified with β-CD-NH₂ can enhance dispersibility and afford the nanoplatform to arrive at the tumor and enter cancer cells easily. After the mouse breast cancer (4T1) cell incubation with the nanoplatform, the abundant glutathione (GSH) in cells cuts the -S-S- bonds like scissors, just as dandelion encountering wind, and the drug doxorubicin (DOX) flows into the nucleus for chemotherapy. Meanwhile, the photodynamic therapy (PDT) effect is enhanced with the decrease content of GSH, which promotes the reactive oxygen species to accumulation. The synergistic chemotherapy and PDT are outstanding in killing 4T1 cells. The rest part UCNPs@C₆₀ possesses excellent biocompatibility and low cytotoxicity. As for cancer diagnosis, UCNPs can be used as a visual imaging agent. Benefited by the delicate structure, all of the functional parts of the nanoplatform go and coordinate well. On account of an FA ligand and the -S-S- bond, the nanoplatform works very well in 4T1 cells while it is able to avoid damage to normal cells since the FA receptors and GSH have overexpression in the 4T1 cells. Thus, this work shows an accessible strategy to design a dandelion-like hierarchical nanoplatform for potential bioimaging-guided synergistic chemo-photodynamic therapy.

Continuous preparation of antimony nanocrystals with near infrared photothermal property by pulsed laser ablation in liquids

Antimony nanocrystals (Sb NCs) are of interest in energy storage, catalysis and cancer therapy for its special physical, chemical and biomedical properties. However, methodology challenges still remain in preparation of colloidal Sb NCs, due to the restricted reaction solution systems, high temperature and time costing for common routes. Herein, size controllable colloidal Sb NCs were continuously prepared by pulsed laser ablation of Sb target in different solvents, owning to the metal nanodroplet explosive ejection and thermal evaporation mechanisms. These well dispersed and stable Sb NCs showed excellent photothermal property in the near-infrared-II window.

Application and prospect of antimonene: A new two-dimensional nanomaterial in cancer theranostics

With the rise of two-dimensional nanomaterials in medicine, finding suitable materials has become our top priority. Since the first report of antimonene in 2015, due to its excellent physical and chemical properties, it has gradually attracted widespread attention, including its application prospects in cancer treatment. In this paper, the preparation, stability and infrared degradability of antimonene, as well as its experimental examples in tumor treatment in recent years are reviewed, the latest research results are listed and summarized, the advantages and existing problems are analyzed, and the future of antimonene in tumor therapy is prospected.

Energy-converting biomaterials for cancer therapy: Category, efficiency, and biosafety

Energy-converting biomaterials (ECBs)-mediated cancer-therapeutic modalities have been extensively explored, which have achieved remarkable benefits to overwhelm the obstacles of traditional cancer-treatment modalities. Energy-driven cancer-therapeutic modalities feature their distinctive merits, including noninvasiveness, low mammalian toxicity, adequate therapeutic outcome, and optimistical synergistic therapeutics. In this advanced review, the prevailing mainstream ECBs can be divided into two sections: Reactive oxygen species (ROS)-associated energy-converting biomaterials (ROS-ECBs) and hyperthermia-related energy-converting biomaterials (H-ECBs). On the one hand, ROS-ECBs can transfer exogenous or endogenous energy (such as light, radiation, ultrasound, or chemical) to generate and release highly toxic ROS for inducing tumor cell apoptosis/necrosis, including photo-driven ROS-ECBs for photodynamic therapy, radiation-driven ROS-ECBs for radiotherapy, ultrasound-driven ROS-ECBs for sonodynamic therapy, and chemical-driven ROS-ECBs for chemodynamic therapy. On the other hand, H-ECBs could translate the external energy (such as light and magnetic) into heat for killing tumor cells, including photo-converted H-ECBs for photothermal therapy and magnetic-converted H-ECBs for magnetic hyperthermia therapy. Additionally, the biosafety issues of ECBs are expounded preliminarily, guaranteeing the ever-stringent requirements of clinical translation. Finally, we discussed the prospects and facing challenges for constructing the new-generation ECBs for establishing intriguing energy-driven cancer-therapeutic modalities. This article is categorized under: Nanotechnology Approaches to Biology >Nanoscale Systems in Biology.

Dissolving Microneedles with Spatiotemporally controlled pulsatile release Nanosystem for Synergistic Chemo-photothermal Therapy of Melanoma

High aggressiveness and recurrence of melanoma tumors require multiple systemic drug administrations, causing discomfort and severe side effects to the patients. Topical treatment strategies that provide repetitively controllable and precise drug administrations will greatly improve treatment effects.

Methods: In this study, a spatiotemporally controlled pulsatile release system, which combined dissolving microneedles (DMNs) and thermal-sensitive solid lipid nanoparticles (SLNs), was constructed to realize multiple doses of dual-modal chemo-photothermal therapy in a single administration. Paclitaxel (PTX) and photothermal agent IR-780 were encapsulated into SLNs and were concentrated in the tips of DMNs (PTX/IR-780 SLNs @DMNs). Equipped with several needles, the DMN patch could be directly inserted into the tumor site and provide a stable “Zone accumulation” to constrain the PTX/IR-780 SLNs at the tumor site with uniform distribution.

Results:In vitro experiments showed that after irradiation with near-infrared light, the PTX/IR-780 SLNs gradually underwent phase transition, thereby accelerating the release of PTX. When irradiation was switched off, the PTX/IR-780 SLNs cooled to re-solidify with limited drug release. Compared with intravenous and intratumoral injections, very few SLNs from PTX/IR-780 SLNs @DMNs were distributed into other organs, resulting in enhanced bioavailability at the tumor site and good safety. In vivo analysis revealed that PTX/IR-780 SLNs @DMNs exhibited significant anti-tumor efficacy. In particular, the primary tumor was completely eradicated with a curable rate of 100% in 30 days and the highest survival rate of 66.67% after 100 days of treatment.

Conclusion: Herein, we developed a DMN system with a unique spatiotemporally controlled pulsatile release feature that provides a user-friendly and low-toxicity treatment route for patients who need long-term and repeat treatments.

Lactosylated IR820/DOX Co-Assembled Nanodrug for Synergetic Antitumour Therapy

Introduction

Synergistic treatment integrating photothermal therapy (PTT) and chemotherapy is a promising strategy for hepatocellular carcinoma (HCC). However, the most commonly used photothermal agent, IR820, and chemotherapeutic drug, doxorubicin hydrochloride (DOX), are both hydrophilic molecules that suffer from the drawbacks of a short circulation time, rapid elimination and off-target effects.

Methods and Results

Herein, a novel nanodrug that combined HCC-targeted IR820 and DOX was developed based on excipient-free co-assembly. First, lactosylated IR820 (LA-IR820) was designed to target HCC. Then, the LA-IR820/DOX nanodrug (LA-IR820/DOX ND) was purely self-assembled without excipient assistance. The physicochemical properties and the chemo-photothermal antitumour activity of the excipient-free LA-IR820/DOX ND were evaluated. More importantly, the obtained LA-IR820/DOX ND exhibited 100% drug loading, remarkable HCC targeting and excellent antitumour efficacy.

Conclusion

This excipient-free LA-IR820/DOX ND may be a promising candidate for the synchronous delivery and synergistic targeting of IR820 and DOX as a combined chemo-photothermal therapy.

Stable and Well-Organized Near-Infrared Platinum(II)-Acetylide-Based Metallacycles-Mediated Cancer Phototherapy

The development of metallacycles with high stability and intense near-infrared (NIR) absorption is important for biomedical applications. However, very few molecular design strategies have been developed on such metallacycles. Herein, we report a new series of stable and well-defined NIR-absorbing metallacycles (M1-M3) through the Pt-acetylide coordination with highly efficient photoconversion performance for cancer phototherapy. The metallacycles showed high stability and strong NIR absorption, and the absorption peaks were red shifted approximately 30 nm in comparison with their corresponding precursors. The introduction of Pt into metallacycles promotes significant photoconversions, including the singlet-to-triplet and nonradiative transitions. Moreover, the fabricated M3 nanoparticles (M3-NPs) showed favorable photoconversions into both thermal effect and singlet oxygen generation upon NIR irradiation, achieving tumor ablation. This novel design of Pt-acetylide metallacycles possesses not only complex topological architectures but also a valuable paradigm for precise cancer phototherapy, which is important for grafting stimuli-responsive functional groups into metallacycles for the development of high-performance biomedical supramolecular materials.