Albumin-coordinated assembly of clearable platinum nanodots for photo-induced cancer theranostics

Polylysine-modified near-infrared-emitting carbon dots assemblies: Amplification of tumor accumulation for enhanced tumor photothermal therapy

A key challenge to enhance the therapeutic outcome of photothermal therapy (PTT) is to improve the efficiency of passive targeted accumulation of photothermal agents at tumor sites. Carbon dots (CDs) are an ideal choice for application as photothermal agents because of their advantages such as adjustable fluorescence, high photothermal conversion efficiency, and excellent biocompatibility. Here, we synthesized polylysine-modified near-infrared (NIR)-emitting CDs assemblies (plys-CDs) through post-solvothermal reaction of NIR-emitting CDs with polylysine. The encapsulated structure of plys-CDs was confirmed by determining morphological, chemical, and luminescent properties. The particle size of CDs increased to approximately 40 ± 8 nm after polylysine modification and was within the size range appropriate for achieving superior enhanced permeability and retention effect. Plys-CDs maintained a high photothermal conversion efficiency of 54.9 %, coupled with increased tumor site accumulation, leading to a high efficacy in tumor PTT. Thus, plys-CDs have a great potential for application in photothermal ablation therapy of tumors.

Metal-Coordinated Polydopamine Structures for Tumor Imaging and Therapy

Meticulously engineered nanomaterials achieve significant advances in the diagnosis and therapy of solid tumors by improving tumor delivery efficiency; and thereby, enhancing imaging and therapeutic efficacy. Currently, polydopamine (PDA) attracts widespread attention because of its biocompatibility, simplicity of preparation, abundant surface groups, and high photothermal conversion efficiency, which can be applied in drug delivery, photothermal therapy, theranostics, and other nanomedicine fields. Inspired by PDA structures that are rich in catechol and amino functional groups that can coordinate with various metal ions, which have charming qualities and characteristics, metal-coordinated PDA structures are exploited for tumor theranostics, but are not thoroughly summarized. Herein, this review summarizes the recent progress in the fabrication of metal-coordinated PDA structures and their availabilities in tumor imaging and therapy, with further in-depth discussion of the challenges and future perspectives of metal-coordinated PDA structures, with the aim that this systematic review can promote interdisciplinary intersections and provide inspiration for the further growth and clinical translation of PDA materials.

Layer-By-Layer Designed Spark-Type AuCuPt Alloy with Robust Broadband Absorption to Enhance Sensitivity in Flexible Detection of Estriol by a Lateral Flow Immunoassay

Excessive intake of estrogen poses significant health risks to the human body; hence, there is a necessity to develop rapid detection methods to monitor its levels of addition. Gold nanoparticles (AuNPs), commonly utilized as colorimetric signal labels, find extensive application in lateral flow immunoassay (LFIA). However, the detection sensitivity of traditional AuNPs-LFIA is typically constrained by low molar extinction coefficients and reliance on a single signal. Herein, in this work, unique spark-type AuCuPt nanoflowers modified with tannic acid (AuCuPt@TA) were precisely designed by reasonable layer-by-layer element composition and green modification. The obtained AuCuPt displays robust broadband absorption spanning the visible to near-infrared spectrum, showcasing a notable molar extinction coefficient of 2.38 × 1012 M-1 cm-1 and a photothermal conversion efficiency of 48.5%. Based on this, selecting estriol (E3) as a model analyte, colorimetric/photothermal dual-signal LFIA (CLFIA and PLFIA) was developed. Limits of detection (LOD) of the CLFIA and PLFIA were achieved at 0.033 ng mL-1 and 0.021 ng mL-1, respectively, which represent a 9.3- and 14.6-fold improvement compared to the visual LOD of AuNPs-LFIA. Moreover, the application feasibility of the immunoassay was further evaluated in the milk and pork with satisfactory recoveries ranging from 86.21% to 117.91%. Thus, this work has enhanced the performance of LFIA for E3 detection and exhibited enormous potential for other sensing platform construction.

Rationalized landscape on protein-based cancer nanomedicine: Recent progress and challenges

The clinical advancement of protein-based nanomedicine has revolutionized medical professionals' perspectives on cancer therapy. Protein-based nanoparticles have been exploited as attractive vehicles for cancer nanomedicine due to their unique properties derived from naturally biomacromolecules with superior biocompatibility and pharmaceutical features. Furthermore, the successful translation of Abraxane™ (paclitaxel-based albumin nanoparticles) into clinical application opened a new avenue for protein-based cancer nanomedicine. In this mini-review article, we demonstrate the rational design and recent progress of protein-based nanoparticles along with their applications in cancer diagnosis and therapy from recent literature. The current challenges and hurdles that hinder clinical application of protein-based nanoparticles are highlighted. Finally, future perspectives for translating protein-based nanoparticles into clinic are identified.

Multifunctional iron-apigenin nanocomplex conducting photothermal therapy and triggering augmented immune response for triple negative breast cancer

Triple negative breast cancer (TNBC) presents a formidable challenge due to its low sensitivity to many chemotherapeutic drugs and a relatively low overall survival rate in clinical practice. Photothermal therapy has recently garnered substantial interest in cancer treatment, owing to its swift therapeutic effectiveness and minimal impact on normal cells. Metal-polyphenol nanostructures have recently garnered significant attention as photothermal transduction agents due to their facile preparation and favorable photothermal properties. In this study, we employed a coordinated approach involving Fe3+ and apigenin, a polyphenol compound, to construct the nanostructure (nFeAPG), with the assistance of β-CD and DSPE-PEG facilitating the formation of the complex nanostructure. In vitro research demonstrated that the formed nFeAPG could induce cell death by elevating intracellular oxidative stress, inhibiting antioxidative system, and promoting apoptosis and ferroptosis, and near infrared spectrum irradiation further strengthen the therapeutic outcome. In 4T1 tumor bearing mice, nFeAPG could effectively accumulate into tumor site and exhibit commendable control over tumor growth. Futher analysis demonstrated that nFeAPG ameliorated the suppressed immune microenvironment by augmenting the response of DC cells and T cells. This study underscores that nFeAPG encompasses a multifaceted capacity to combat TNBC, holding promise as a compelling therapeutic strategy for TNBC treatment.

The application of nanoparticles-based ferroptosis, pyroptosis and autophagy in cancer immunotherapy

Immune checkpoint blockers (ICBs) have been applied for cancer therapy and achieved great success in the field of cancer immunotherapy. Nevertheless, the broad application of ICBs is limited by the low response rate. To address this issue, increasing studies have found that the induction of immunogenic cell death (ICD) in tumor cells is becoming an emerging therapeutic strategy in cancer treatment, not only straightly killing tumor cells but also enhancing dying cells immunogenicity and activating antitumor immunity. ICD is a generic term representing different cell death modes containing ferroptosis, pyroptosis, autophagy and apoptosis. Traditional chemotherapeutic agents usually inhibit tumor growth based on the apoptotic ICD, but most tumor cells are resistant to the apoptosis. Thus, the induction of non-apoptotic ICD is considered to be a more efficient approach for cancer therapy. In addition, due to the ineffective localization of ICD inducers, various types of nanomaterials have been being developed to achieve targeted delivery of therapeutic agents and improved immunotherapeutic efficiency. In this review, we briefly outline molecular mechanisms of ferroptosis, pyroptosis and autophagy, as well as their reciprocal interactions with antitumor immunity, and then summarize the current progress of ICD-induced nanoparticles based on different strategies and illustrate their applications in the cancer therapy.

Synergistic Phototherapy-Molecular Targeted Therapy Combined with Tumor Exosome Nanoparticles for Oral Squamous Cell Carcinoma Treatment

Oral squamous cell carcinoma (OSCC) contributes to more than 90% of all oral malignancies, yet the performance of traditional treatments is impeded by limited therapeutic effects and substantial side effects. In this work, we report a combinational treatment strategy based on tumor exosome-based nanoparticles co-formulating a photosensitizer (Indocyanine green) and a tyrosine kinase inhibitor (Gefitinib) (IG@EXOs) for boosting antitumor efficiency against OSCC through synergistic phototherapy-molecular targeted therapy. The IG@EXOs generate distinct photothermal/photodynamic effects through enhanced photothermal conversion efficiency and ROS generation, respectively. In vivo, the IG@EXOs efficiently accumulate in the tumor and penetrate deeply to the center of the tumor due to passive and homologous targeting. The phototherapy effects of IG@EXOs not only directly induce potent cancer cell damage but also promote the release and cytoplasmic translocation of Gefitinib for achieving significant inhibition of cell proliferation and tumor angiogenesis, eventually resulting in efficient tumor ablation and lymphatic metastasis inhibition through the synergistic phototherapy-molecular targeted therapy. We envision that the encouraging performances of IG@EXOs against cancer pave a new avenue for their future application in clinical OSCC treatment.

Heavy Metal-Based Nanoparticles as High-Performance X-ray Computed Tomography Contrast Agents

X-ray computed tomography (CT) contrast agents offer extremely valuable tools and techniques in diagnostics via contrast enhancements. Heavy metal-based nanoparticles (NPs) can provide high contrast in CT images due to the high density of heavy metal atoms with high X-ray attenuation coefficients that exceed that of iodine (I), which is currently used in hydrophilic organic CT contrast agents. Nontoxicity and colloidal stability are vital characteristics in designing heavy metal-based NPs as CT contrast agents. In addition, a small particle size is desirable for in vivo renal excretion. In vitro phantom imaging studies have been performed to obtain X-ray attenuation efficiency, which is a critical parameter for CT contrast agents, and the imaging performance of CT contrast agents has been demonstrated via in vivo experiments. In this review, we focus on the in vitro and in vivo studies of various heavy metal-based NPs in pure metallic or chemical forms, including Au, Pt, Pd, Ag, Ce, Gd, Dy, Ho, Yb, Ta, W, and Bi, and provide an outlook on their use as high-performance CT contrast agents.

Platinum based theranostics nanoplatforms for antitumor applications

Platinum (Pt) based nanoplatforms are biocompatible nanoagents with photothermal antitumor performance, while exhibiting excellent radiotherapy sensitization properties. Pt-nanoplatforms have extensive research prospects in the realm of cancer treatment due to their highly selective and minimally invasive treatment mode with low damage, and integrated diagnosis and treatment with image monitoring and collaborative drug delivery. Platinum based anticancer chemotherapeutic drugs can kill tumor cells by damaging DNA through chemotherapy. Meanwhile, Pt-nanoplatforms also have good electrocatalytic activity, which can mediate novel electrodynamic therapy. Simultaneously, Pt(II) based compounds also have potential as photosensitizers in photodynamic therapy for malignant tumors. Pt-nanoplatforms can also modulate the immunosuppressive environment and synergistically ablate tumor cells in combination with immune checkpoint inhibitors. This article reviews the research progress of platinum based nanoplatforms in new technologies for cancer therapy, starting from widely representative examples of platinum based nanoplatforms in chemotherapy, electrodynamic therapy, photodynamic therapy, photothermal therapy, and immunotherapy. Finally, multimodal imaging techniques of platinum based nanoplatforms for biomedical diagnosis are briefly discussed.

Reactive oxidative species (ROS)-based nanomedicine for BBB crossing and glioma treatment: current status and future directions

Glioma is the most common primary intracranial tumor in adults with poor prognosis. Current clinical treatment for glioma includes surgical resection along with chemoradiotherapy. However, the therapeutic efficacy is still unsatisfactory. The invasive nature of the glioma makes it impossible to completely resect it. The presence of blood-brain barrier (BBB) blocks chemotherapeutic drugs access to brain parenchyma for glioma treatment. Besides, tumor heterogeneity and hypoxic tumor microenvironment remarkably limit the efficacy of radiotherapy. With rapid advances of nanotechnology, the emergence of a new treatment approach, namely, reactive oxygen species (ROS)-based nanotherapy, provides an effective approach for eliminating glioma via generating large amounts of ROS in glioma cells. In addition, the emerging nanotechnology also provides BBB-crossing strategies, which allows effective ROS-based nanotherapy of glioma. In this review, we summarized ROS-based nanomedicine and their application in glioma treatment, including photodynamic therapy (PDT), photothermal therapy (PTT), chemodynamic therapy (CDT), sonodynamic therapy (SDT), radiation therapy, etc. Moreover, the current challenges and future prospects of ROS-based nanomedicine are also elucidated with the intention to accelerate its clinical translation.

Nanotechnology-based photo-immunotherapy: a new hope for inhibition of melanoma growth and metastasis

Melanoma is the most aggressive form of skin cancer and there is a need for the development of effective anti-melanoma therapies as it shows high metastatic ability and low response rate. In addition, it has been identified that traditional phototherapy could trigger immunogenic cell death (ICD) to activate antitumor immune response, which could not only effectively arrest primary tumor growth, but also exhibit superior effects in terms of anti-metastasis, anti-recurrence for metastatic melanoma treatment However, the limited tumor accumulation of photosensitizers/photothermal agents and immunosuppressive tumor microenvironment severely weaken the immune effects. The application of nanotechnology facilitates a higher accumulation of photosensitizers/photothermal agents at the tumor site, which can thus improve the antitumor effects of photo-immunotherapy (PIT). In this review, we summarize the basic principles of nanotechnology-based PIT and highlight novel nanotechnologies that are expected to enhance the antitumor immune response for improved therapeutic efficacy.

Proteins and their functionalization for finding therapeutic avenues in cancer: Current status and future prospective

Despite the remarkable advancement in the health care sector, cancer remains the second most fatal disease globally. The existing conventional cancer treatments primarily include chemotherapy, which has been associated with little to severe side effects, and radiotherapy, which is usually expensive. To overcome these problems, target-specific nanocarriers have been explored for delivering chemo drugs. However, recent reports on using a few proteins having anticancer activity and further use of them as drug carriers have generated tremendous attention for furthering the research towards cancer therapy. Biomolecules, especially proteins, have emerged as suitable alternatives in cancer treatment due to multiple favourable properties including biocompatibility, biodegradability, and structural flexibility for easy surface functionalization. Several in vitro and in vivo studies have reported that various proteins derived from animal, plant, and bacterial species, demonstrated strong cytotoxic and antiproliferative properties against malignant cells in native and their different structural conformations. Moreover, surface tunable properties of these proteins help to bind a range of anticancer drugs and target ligands, thus making them efficient delivery agents in cancer therapy. Here, we discuss various proteins obtained from common exogenous sources and how they transform into effective anticancer agents. We also comprehensively discuss the tumor-killing mechanisms of different dietary proteins such as bovine α-lactalbumin, hen egg-white lysozyme, and their conjugates. We also articulate how protein nanostructures can be used as carriers for delivering cancer drugs and theranostics, and strategies to be adopted for improving their in vivo delivery and targeting. We further discuss the FDA-approved protein-based anticancer formulations along with those in different phases of clinical trials.

Novel strategies for tumor radiosensitization mediated by multifunctional gold-based nanomaterials

Radiotherapy (RT) is one of the most effective and commonly used cancer treatments for malignant tumors. However, the existing radiosensitizers have a lot of side effects and poor efficacy, which limits the curative effect and further application of radiotherapy. In recent years, emerging nanomaterials have shown unique advantages in enhancing radiosensitization. In particular, gold-based nanomaterials, with high X-ray attenuation capacity, good biocompatibility, and promising chemical, electronic and optical properties, have become a new type of radiotherapy sensitizer. In addition, gold-based nanomaterials can be used as a carrier to load a variety of drugs and immunosuppressants; in particular, its photothermal therapy, photodynamic therapy and multi-mode imaging functions aid in providing excellent therapeutic effect in coordination with RT. Recently, many novel strategies of radiosensitization mediated by multifunctional gold-based nanomaterials have been reported, which provides a new idea for improving the efficacy and reducing the side effects of RT. In this review, we systematically summarize the recent progress of various new gold-based nanomaterials that mediate radiosensitization and describe the mechanism. We further discuss the challenges and prospects in the field. It is hoped that this review will help researchers understand the latest progress of gold-based nanomaterials for radiosensitization, and encourage people to optimize the existing methods or explore novel approaches for radiotherapy.

Self-Assembly of Precisely Fluorinated Albumin for Dual Imaging-Guided Synergistic Chemo-Photothermal-Photodynamic Cancer Therapy

Although albumin has been extensively used in nanomedicine, it is still challenging to fluorinate albumin into fluorine-19 magnetic resonance imaging (¹⁹F MRI)-traceable theranostics because existing strategies lead to severe ¹⁹F signal splitting, line broadening, and low ¹⁹F MRI sensitivity. To this end, 34-cysteine-selectively fluorinated bovine serum albumins (BSAs) with a sharp singlet ¹⁹F peak have been developed as ¹⁹F MRI-sensitive and self-assembled frameworks for cancer theranostics. It was found that fluorinated albumin with a non-binding fluorocarbon and a long linker is crucial for avoiding ¹⁹F signal splitting and line broadening. With the fluorinated BSAs, paclitaxel (PTX) and IR-780 were self-assembled into stable, monodisperse, and multifunctional nanoparticles in a framework-promoted self-emulsion way. The high tumor accumulation, efficient cancer cell uptake, and laser-triggered PTX sharp release of the BSA nanoparticles enabled ¹⁹F MRI-near infrared fluorescence imaging (NIR FLI)-guided synergistic chemotherapy (Chemo), photothermal and photodynamic therapy of xenograft MCF-7 cancer with a high therapeutical index in mice. This study developed a rational synthesis of ¹⁹F MRI-sensitive albumin and a framework-promoted self-emulsion of multifunctional BSA nanoparticles, which would promote the development of protein-based high-performance biomaterials for imaging, diagnosis, therapy, and beyond.

NIR-Activated Thermosensitive Liposome-Gold Nanorod Hybrids for Enhanced Drug Delivery and Stimulus Sensitivity

Combinatorial photothermal therapy and chemotherapy is an extremely promising tumor therapeutic modality. However, such systems still remain challenges in stimulus sensitivity, avoiding drug leakage, and therapeutic safety. To solve these problems, we engineered actively loaded doxorubicin (DOX) and gold nanorod (GNR) liposomes through embedding stiff hollow mesoporous silica nanoparticles (HMSNs) in the liposomal water cavity (HMLGDB) to resist the influence of shear force of GNRs to prevent drug leakage. Under 808 nm laser irradiation, the ambient temperature was raised greatly because of the photothermal conversion of GNRs, thereby rupturing the lipid layer and then triggering the DOX release. The results of in vitro experiments showed that the low concentration of HMLGDB (15 μg/mL) could effectively overcome the MCF-7 cells (human breast cancer cell line) by the increase of DOX concentration intracellularly and the good photothermal effect of GNRs. After intravenous injection, HMLGDB exhibited intratumor aggregation and PTT capacity. Furthermore, the combined chemo-photothermal antitumor strategy demonstrated a high inhibition of tumor growth and low damage to normal tissues. The developed hybrids provide a paradigm for efficient combinatorial photothermal therapy (PTT) and chemotherapy (CT).

Albumin-templated platinum (II) sulfide nanodots for size-dependent cancer theranostics

Transition-metal chalcogenides, such as noble metal chalcogenides, hold tremendous potential as efficient agents for photo-induced cancer theranostics due to their unique physicochemical properties. However, a critical bottleneck still lies in exploring simple and controllable methods to synthesize noble metal chalcogenides especially PtS for in vivo photo-induced cancer imaging and simultaneous therapy. Herein, we proposed the albumin-templated synthesis of size-controllable platinum (II) sulfide nanodots (PtS-NDs) for multimodal cancer imaging and potent photothermal therapy. PtS-NDs were precisely synthesized with a tunable size ranging from 2.1 nm to 4.5 nm through a thermodynamically controlled growth inside albumin nanocages. PtS-NDs yielded significant near-infrared (NIR) absorbance and outstanding photothermal conversion under NIR laser irradiation, as well as effective resistance to photobleaching, thereby generating remarkable in vivo photoacoustic signals and distinct hyperthermia at tumor site. Moreover, these nanodots possessed efficient cellular uptake and tumor targeting capabilities in a size-dependent manner, thus leading to controllable diagnostic and thermo-therapeutic efficacy. Specifically, PtS-NDs with core diameter of 4.5 nm displayed preferable in vivo photoacoustic and CT imaging with high sensitivity, spatially and anatomically enhanced imaging contrast, together with hyperthermia mediated tumor ablation. Thus, the albumin-templated biomimetic synthesis provided an insightful strategy on fabricating theranostic PtS-NDs for potential clinical applications. STATEMENT OF SIGNIFICANCE: Noble metal chalcogenides especially PtS are of particular importance in the field of precise nanomedicine to improve both accuracy of cancer diagnosis and efficiency of tumor treatment. However, the intensively preclinical investigation of PtS was limited due to the lack of simple and controllable synthetic methods. Here, we report an albumin-templated biomineralization synthesis of platinum (II) sulfide nanodots (PtS-NDs). Specifically, albumin-templated biomineralization of PtS-NDs was induced by the electrostatic interactions between albumin and Pt²⁺, followed by the nucleation and growth inside the albumin nanocages. The resulting PtS-NDs showed good dispersibility and biosafety, as well as size-dependent photophysical properties and biological behaviors. Therefore, albumin-based biomineralization is a promising and safe strategy to facilely fabricate Pt-based chalcogenide for tumor theranostics.

Combined Photodynamic and Photothermal Therapy and Immunotherapy for Cancer Treatment: A Review

Photoactivation therapy based on photodynamic therapy (PDT) and photothermal therapy (PTT) has been identified as a tumour ablation modality for numerous cancer indications, with photosensitisers and photothermal conversion agents playing important roles in the phototherapy process, especially in recent decades. In addition, the iteration of nanotechnology has strongly promoted the development of phototherapy in tumour treatment. PDT can increase the sensitivity of tumour cells to PTT by interfering with the tumour microenvironment, whereas the heat generated by PTT can increase blood flow, improve oxygen supply and enhance the PDT therapeutic effect. In addition, tumour cell debris generated by phototherapy can serve as tumour-associated antigens, evoking antitumor immune responses. In this review, the research progress of phototherapy, and its research effects in combination with immunotherapy on the treatment of tumours are mainly outlined, and issues that may need continued attention in the future are raised.

Emerging platinum(0) nanotherapeutics for efficient cancer therapy

Platinum (Pt)-based chemotherapy has been necessary for clinical cancer treatment. However, traditional bivalent drugs are hindered by poor physicochemical properties, severe toxic side effects, and drug resistance. Currently, elemental Pt(0) nanotherapeutics (NTs) have emerged to tackle the dilemma. The inherent acid-responsiveness of Pt(0) NTs could help to improve tumor selectivity and alleviate toxic effects. Moreover, the metal nature of Pt facilitates the great combination of Pt(0) NTs with photothermal and photodynamic therapy and imaging-guided diagnosis. Based on recent important researches, this review provides an updated introduction to Pt(0) NTs. First, the challenges of traditional Pt-based chemotherapy have been outlined. Then, Pt(0) NTs with multiple applications of tumor theranostics have been overviewed. Furthermore, the combinations of Pt(0) NTs with other therapeutical modalities are introduced. Last but not least, we envision the possible challenges and prospects associated with Pt(0) NTs.

Biomedical Photoacoustic Imaging for Molecular Detection and Disease Diagnosis: "Always-On" and "Turn-On" Probes

Photoacoustic (PA) imaging is a nonionizing, noninvasive imaging technique that combines optical and ultrasonic imaging modalities to provide images with excellent contrast, spatial resolution, and penetration depth. Exogenous PA contrast agents are created to increase the sensitivity and specificity of PA imaging and to offer diagnostic information for illnesses. The existing PA contrast agents are categorized into two groups in this review: "always-on" and "turn-on," based on their ability to be triggered by target molecules. The present state of these probes, their merits and limitations, and their future development, is explored.

Platinum nanoplatforms: classic catalysts claiming a prominent role in cancer therapy

Platinum nanoparticles (Pt NPs) have a well-established role as a classic heterogeneous catalyst. Also, Pt has traditionally been employed as a component of organometallic drug formulations for chemotherapy. However, a new role in cancer therapy is emerging thanks to its outstanding catalytic properties, enabling novel approaches that are surveyed in this review. Herein, we critically discuss results already obtained and attempt to ascertain future perspectives for Pt NPs as catalysts able to modify key processes taking place in the tumour microenvironment (TME). In addition, we explore relevant parameters affecting the cytotoxicity, biodistribution and clearance of Pt nanosystems. We also analyze pros and cons in terms of biocompatibility and potential synergies that emerge from combining the catalytic capabilities of Pt with other agents such as co-catalysts, external energy sources (near-infrared light, X-ray, electric currents) and conventional therapies.

pH-responsive albumin-coated biopolymeric nanoparticles with lapatinab for targeted breast cancer therapy

One can enhance the therapeutic index of anti-cancer drugs using albumin as a tumor homing agent for targeted cancer therapy. Herein, we sought to load lapatinib (LAPA) into small albumin-coated biopolymeric (poly-lactic co-glycolic acid (PLGA)) nanoparticles (APL NPs) by an emulsification method to improve the anti-tumor efficacy of lapatinib. The prepared APL NPs exhibited a small spherical core with an average diameter of 120.5 ± 10.2 nm with a narrow particle size distribution, high drug loading capacity (LC of 9.65 ± 1.53 %), good entrapment efficiency (EE of 75.55 ± 3.25 %), enhanced colloidal stability and a pH-responsive controlled drug release profile. Their cell-uptake and cancer cell growth inhibition were significantly higher compared to free LAPA and uncoated PLGA-LAPA (UPL) NPs, most likely because aggressive breast tumor cells over-express albumin receptors and utilize albumin as nutrient source for their growth. In addition, APL NPs possessed enhanced tumor accumulation and prolonged blood residence time compared to free LAPA and UPL NPs, allowing for potent tumor growth inhibition while exhibiting excellent biosafety. In short, the current study exploited a new and simple strategy to concurrently improve the safety and efficacy of LAPA for breast cancer treatment.

Research Progress of Conjugated Nanomedicine for Cancer Treatment

The conventional cancer therapeutic modalities include surgery, chemotherapy and radiotherapy. Although immunotherapy and targeted therapy are also widely used in cancer treatment, chemotherapy remains the cornerstone of tumor treatment. With the rapid development of nanotechnology, nanomedicine is believed to be an emerging field to further improve the efficacy of chemotherapy. Until now, there are more than 17 kinds of nanomedicine for cancer therapy approved globally. Thereinto, conjugated nanomedicine, as an important type of nanomedicine, can not only possess the targeted delivery of chemotherapeutics with great precision but also achieve controlled drug release to avoid adverse effects. Meanwhile, conjugated nanomedicine provides the platform for combining several different therapeutic approaches (chemotherapy, photothermal therapy, photodynamic therapy, thermodynamic therapy, immunotherapy, etc.) with the purpose of achieving synergistic effects during cancer treatment. Therefore, this review focuses on conjugated nanomedicine and its various applications in synergistic chemotherapy. Additionally, the further perspectives and challenges of the conjugated nanomedicine are also addressed, which clarifies the design direction of a new generation of conjugated nanomedicine and facilitates the translation of them from the bench to the bedside.

Antitumor Applications of Photothermal Agents and Photothermal Synergistic Therapies

As a new tumor treatment strategy, photothermal therapy (PTT) has the advantages of accuracy, ease of administration, a high efficiency and low side effects. Photothermal transduction agents (PTAs) are the key factor which play an important role in PTT. The mechanism of PTT is discussed in detail. The photothermal conversion efficiency (PCE) can be improved by increasing the light absorption and reducing the light scattering of photothermal conversion agents. Additionally, non-radiative relaxation path attenuation can also promote energy conversion to obtain a higher value in terms of PCE. The structure and photothermal characteristics of various kinds of PTAs (metal materials, carbon-based nanomaterials, two-dimensional nanomaterials, and organic materials) were compared and analyzed. This paper reviews the antitumor applications of photothermal synergistic therapies, including PTT combined with immunotherapy, chemotherapy, and photodynamic therapy. This review proposes that these PTAs promote the development of photothermal synergistic therapies and have a great potential in the application of tumor treatment.

Nano-bio interactions: A major principle in the dynamic biological processes of nano-assemblies

Controllable nano-assembly with stimuli-responsive groups is emerging as a powerful strategy to generate theranostic nanosystems that meet unique requirements in modern medicine. However, this prospective field is still in a proof-of-concept stage due to the gaps in our understanding of complex-(nano-assemblies)-complex-(biosystems) interactions. Indeed, stimuli-responsive assembly-disassembly is, in and of itself, a process of nano-bio interactions, the key steps for biological fate and functional activity of nano-assemblies. To provide a comprehensive understanding of these interactions in this review, we first propose a 4W1H principle (Where, When, What, Which and How) to delineate the relevant dynamic biological processes, behaviour and fate of nano-assemblies. We further summarize several key parameters that govern effective nano-bio interactions. The effects of these kinetic parameters on ADMET processes (absorption, distribution, metabolism, excretion and transformation) are then discussed. Furthermore, we provide an overview of the challenges facing the evaluation of nano-bio interactions of assembled nanodrugs. We finally conclude with future perspectives on safe-by-design and application-driven-design of nano-assemblies. This review will highlight the dynamic biological and physicochemical parameters of nano-bio interactions and bridge discrete concepts to build a full spectrum understanding of the biological outcomes of nano-assemblies. These principles are expected to pave the way for future development and clinical translation of precise, safe and effective nanomedicines with intelligent theranostic features.

Targeting Cancer Stem Cells: Therapeutic and diagnostic strategies by the virtue of nanoparticles

Cancer stem cells (CSCs) are the subpopulation of cells present within a tumor with the properties of self-renewing, differentiating, and proliferating. Owing to the presence of ATP-binding cassette drug pumps and increased expression of anti-apoptotic proteins, the conventional chemotherapeutic agents have failed to eliminate CSCs resulting in relapse and resistance of cancer. Therefore, to obtain long-lasting clinical responses and avoid the recurrence of cancer, it is crucial to develop an efficient strategy targeting CSCs by either employing a differentiation therapy or specifically delivering drugs to CSCs. Several intracellular and extracellular cancer specific biomarkers are overexpressed by CSCs and are utilized as targets for the development of new approaches in the diagnosis and treatment of CSCs. Moreover, several nanostructured particles, alone or in combination with current treatment approaches, have been used to improve the detection, imaging, and targeting of CSCs, thus addressing the limitations of cancer therapies. Targeting CSC surface markers, stemness-related signaling pathways, and tumor microenvironmental signals has improved the detection and eradication of CSCs and, therefore, tumor diagnosis and treatment. This review summarizes a variety of promising nanoparticles targeting the surface biomarkers of CSCs for the detection and eradication of tumor-initiating stem cells, used in combination with other treatment regimens.

Surface-Functionalized NdVO4:Gd3+ Nanoplates as Active Agents for Near-Infrared-Light-Triggered and Multimodal-Imaging-Guided Photothermal Therapy

Development of nanotheranostic agents with near-infrared (NIR) absorption offers an effective tool for fighting malignant diseases. Lanthanide ion neodymium (Nd³⁺)-based nanomaterials, due to the maximum absorption at around 800 nm and unique optical properties, have caught great attention as potential agents for simultaneous cancer diagnosis and therapy. Herein, we employed an active nanoplatform based on gadolinium-ion-doped NdVO₄ nanoplates (NdVO₄:Gd³⁺ NPs) for multiple-imaging-assisted photothermal therapy. These NPs exhibited enhanced NIR absorption and excellent biocompatibility after being grafted with polydopamine (pDA) and bovine serum albumin (BSA) layers on their surface. Upon expose to an 808 nm laser, these resulting NPs were able to trigger hyperthermia rapidly and cause photo-destruction of cancer cells. In a xenograft tumor model, tumor growth was also significantly inhibited by these photothermal agents under NIR laser irradiation. Owing to the multicomponent nanostructures, we demonstrated these nanoagents as being novel contrast agents for in vivo magnetic resonance (MR) imaging, X-ray computed tomography (CT), photoacoustic (PA) imaging, and second biological window fluorescent imaging of tumor models. Thus, we believe that this new kind of nanotherapeutic will benefit the development of emerging nanosystems for biological imaging and cancer therapy.

Heptamethine Cyanine–Based Application for Cancer Theranostics

Cancer is the most common life-threatening malignant disease. The future of personalized cancer treatments relies on the development of functional agents that have tumor-targeted anticancer activities and can be detected in tumors through imaging. Cyanines, especially heptamethine cyanine (Cy7), have prospective application because of their excellent tumor-targeting capacity, high quantum yield, low tissue autofluorescence, long absorption wavelength, and low background interference. In this review, the application of Cy7 and its derivatives in tumors is comprehensively explored. Cy7 is enormously acknowledged in the field of non-invasive therapy that can “detect” and “kill” tumor cells via near-infrared fluorescence (NIRF) imaging, photothermal therapy (PTT), and photodynamic therapy (PDT). Furthermore, Cy7 is more available and has excellent properties in cancer theranostics by the presence of multifunctional nanoparticles via fulfilling multimodal imaging and combination therapy simultaneously. This review provides a comprehensive scope of Cy7’s application for cancer NIRF imaging, phototherapy, nanoprobe-based combination therapy in recent years. A deeper understanding of the application of imaging and treatment underlying Cy7 in cancer may provide new strategies for drug development based on cyanine. Thus, the review will lead the way to new types with optical properties and practical transformation to clinical practice.

Exogenous Contrast Agents in Photoacoustic Imaging: An In Vivo Review for Tumor Imaging

The field of cancer theranostics has grown rapidly in the past decade and innovative 'biosmart' theranostic materials are being synthesized and studied to combat the fast growth of cancer metastases. While current state-of-the-art oncology imaging techniques have decreased mortality rates, patients still face a diminished quality of life due to treatment. Therefore, improved diagnostics are needed to define in vivo tumor growths on a molecular level to achieve image-guided therapies and tailored dosage needs. This review summarizes in vivo studies that utilize contrast agents within the field of photoacoustic imaging-a relatively new imaging modality-for tumor detection, with a special focus on imaging and transducer parameters. This paper also details the different types of contrast agents used in this novel diagnostic field, i.e., organic-based, metal/inorganic-based, and dye-based contrast agents. We conclude this review by discussing the challenges and future direction of photoacoustic imaging.

Intrinsically radiopaque biomaterial assortments: a short review on the physical principles, X-ray imageability, and state-of-the-art developments

X-ray attenuation ability, otherwise known as radiopacity of a material, could be indisputably tagged as the central and decisive parameter that produces contrast in an X-ray image. Radiopaque biomaterials are vital in the healthcare sector that helps clinicians to track them unambiguously during pre and post interventional radiological procedures. Medical imaging is one of the most powerful resources in the diagnostic sector that aids improved treatment outcomes for patients. Intrinsically radiopaque biomaterials enable themselves for visual targeting/positioning as well as to monitor their fate and further provide the radiologists with critical insights about the surgical site. Moreover, the emergence of advanced real-time imaging modalities is a boon to the contemporary healthcare systems that allow to perform minimally invasive surgical procedures and thereby reduce the healthcare costs and minimize patient trauma. X-ray based imaging is one such technologically upgraded diagnostic tool with many variants like digital X-ray, computed tomography, digital subtraction angiography, and fluoroscopy. In light of these facts, this review is aimed to briefly consolidate the physical principles of X-ray attenuation by a radiopaque material, measurement of radiopacity, classification of radiopaque biomaterials, and their recent advanced applications.

Mitochondria-Targeted Nanomedicine for Enhanced Efficacy of Cancer Therapy

Nanomedicines have been designed and developed to deliver anticancer drugs or exert anticancer therapy more selectively to tumor sites. Recent investigations have gone beyond delivering drugs to tumor tissues or cells, but to intracellular compartments for amplifying therapy efficacy. Mitochondria are attractive targets for cancer treatment due to their important functions for cells and close relationships to tumor occurrence and metastasis. Accordingly, multifunctional nanoplatforms have been constructed for cancer therapy with the modification of a variety of mitochondriotropic ligands, to trigger the mitochondria-mediated apoptosis of tumor cells. On this basis, various cancer therapeutic modalities based on mitochondria-targeted nanomedicines are developed by strategies of damaging mitochondria DNA (mtDNA), increasing reactive oxygen species (ROS), disturbing respiratory chain and redox balance. Herein, in this review, we highlight mitochondria-targeted cancer therapies enabled by nanoplatforms including chemotherapy, photothermal therapy (PTT), photodynamic therapy (PDT), chemodynamic therapy (CDT), sonodynamic therapy (SDT), radiodynamic therapy (RDT) and combined immunotherapy, and discussed the ongoing challenges.

A pH-responsive Pt-based nanoradiosensitizer for enhanced radiotherapy via oxidative stress amplification

Tumor radioresistance is a major issue in radiotherapy. To address it, a pH-responsive nanoradiosensitizer was synthesized employing a simple method. Initially, chloroplatinic acid was reduced by human serum albumin (HSA) to form HSA-wrapped Pt@HSA nanoparticles (NPs). Subsequently, cinnamicaldehyde (CA) was grafted on Pt@HSA via aldimine condensation to obtain nanoradiosensitizer Pt@HSA/CA NPs. CA would be released in tumor cells (pH = 5.5) to induce the production of reactive oxygen species, including H₂O₂, ˙OH, etc. The increased decomposition of H₂O₂ catalyzed by the NPs resulted in enhanced production of oxygen, leading to hypoxia relief of the tumor cells, which is beneficial for radiotherapy. Due to the high X-ray attenuation coefficient of Pt, Pt@HSA/CA NPs enhance the energy deposition of radiation. Cytotoxicity assay revealed that Pt@HSA/CA NPs resulted in a cell death rate of 77%, which was 24.4% higher than that of Pt@HSA NPs even under low-dose X-ray irradiation of 4 Gy. Colony formation assay demonstrated that the sensitization enhancement ratio was 1.37, indicating that Pt@HSA/CA NPs displayed remarkable radiosensitizing ability. Notably, in vivo results indicated that the NPs could increase the tumor inhibition rate to 91.2% with negligible side effects to normal tissues. These results demonstrate that Pt@HSA/CA NPs had outstanding tumor curative efficacy and hypotoxicity.

Mutual-reinforcing sonodynamic therapy against Rheumatoid Arthritis based on sparfloxacin sonosensitizer doped concave-cubic rhodium nanozyme

Rheumatoid arthritis (RA) is an autoimmune disease associated with synovitis and cartilage destruction. Ultrasound (US)-driven sonodynamic therapy (SDT) possess a good application prospect in RA therapy because of its non-invasiveness and strong tissue penetration capabilities, which can kill activated synovial inflammatory cells. Nevertheless, the tiny accumulation of sonosensitizers in the joints and the hypoxic synovial microenvironment severely limit the therapeutic effect of SDT. Hence, we developed a sonosensitizer spafloxacin (SPX) doped and human serum albumin (HSA) loaded concave-cubic rhodium (Rh) nanozyme (Rh/SPX-HSA) to realize mutual-reinforcing SDT during ultrasonic activation. On the one hand, SPX would cause mitochondrial dysfunction by inducing excessive reactive oxygen species (ROS) production, thus suppressing fibroblast-like synoviocyte (FLS) under US conditions. On the other hand, concave-cubic rhodium was utilized as a nanozyme with endogenous peroxidase (POD) and catalase (CAT)-like enzyme activities, which not only relieved the hypoxia of the joint to resist angiogenesis, but also enormously ascended the SDT efficacy by rising ¹O₂ levels. Interestingly, the activity of nanozymes was also improved by the ultrasonic cavitation effect, thereby realizing mutual-reinforcing SDT. Overall, our strategy provided Rh-based to achieve effective SDT under hypoxic microenvironment, which offered a promising prospect for highly efficient treatment of RA.

Endogenous Conjugation of Biomimetic Dinitrosyl Iron Complex with Protein Vehicles for Oral Delivery of Nitric Oxide to Brain and Activation of Hippocampal Neurogenesis

Nitric oxide (NO), a pro-neurogenic and antineuroinflammatory gasotransmitter, features the potential to develop a translational medicine against neuropathological conditions. Despite the extensive efforts made on the controlled delivery of therapeutic NO, however, an orally active NO prodrug for a treatment of chronic neuropathy was not reported yet. Inspired by the natural dinitrosyl iron unit (DNIU) [Fe(NO)₂], in this study, a reversible and dynamic interaction between the biomimetic [(NO)₂Fe(μ-SCH₂CH₂OH)₂Fe(NO)₂] (DNIC-1) and serum albumin (or gastrointestinal mucin) was explored to discover endogenous proteins as a vehicle for an oral delivery of NO to the brain after an oral administration of DNIC-1. On the basis of the in vitro and in vivo study, a rapid binding of DNIC-1 toward gastrointestinal mucin yielding the mucin-bound dinitrosyl iron complex (DNIC) discovers the mucoadhesive nature of DNIC-1. A reversible interconversion between mucin-bound DNIC and DNIC-1 facilitates the mucus-penetrating migration of DNIC-1 shielded in the gastrointestinal tract of the stomach and small intestine. Moreover, the NO-release reactivity of DNIC-1 induces the transient opening of the cellular tight junction and enhances its paracellular permeability across the intestinal epithelial barrier. During circulation in the bloodstream, a stoichiometric binding of DNIC-1 to the serum albumin, as another endogenous protein vehicle, stabilizes the DNIU [Fe(NO)₂] for a subsequent transfer into the brain. With aging mice under a Western diet as a disease model for metabolic syndrome and cognitive impairment, an oral administration of DNIC-1 in a daily manner for 16 weeks activates the hippocampal neurogenesis and ameliorates the impaired cognitive ability. Taken together, these findings disclose the synergy between biomimetic DNIC-1 and endogenous protein vehicles for an oral delivery of therapeutic NO to the brain against chronic neuropathy.

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.

Tumor-targeting inorganic nanomaterials synthesized by living cells

Inorganic nanomaterials (NMs) have shown potential application in tumor-targeting theranostics, owing to their unique physicochemical properties. Some living cells in nature can absorb surrounding ions in the environment and then convert them into nanomaterials after a series of intracellular/extracellular biochemical reactions. Inspired by that, a variety of living cells have been used as biofactories to produce metallic/metallic alloy NMs, metalloid NMs, oxide NMs and chalcogenide NMs, which are usually automatically capped with biomolecules originating from the living cells, benefitting their tumor-targeting applications. In this review, we summarize the biosynthesis of inorganic nanomaterials in different types of living cells including bacteria, fungi, plant cells and animal cells, accompanied by their application in tumor-targeting theranostics. The mechanisms involving inorganic-ion bioreduction and detoxification as well as biomineralization are emphasized. Based on the mechanisms, we describe the size and morphology control of the products via the modulation of precursor ion concentration, pH, temperature, and incubation time, as well as cell metabolism by a genetic engineering strategy. The strengths and weaknesses of these biosynthetic processes are compared in terms of the controllability, scalability and cooperativity during applications. Future research in this area will add to the diversity of available inorganic nanomaterials as well as their quality and biosafety.

Synergistic enhancement of immunological responses triggered by hyperthermia sensitive Pt NPs via NIR laser to inhibit cancer relapse and metastasis

The combination of tumor ablation and immunotherapy is a promising strategy against tumor relapse and metastasis. Photothermal therapy (PTT) triggers the release of tumor-specific antigens and damage associated molecular patterns (DAMPs) in-situ. However, the immunosuppressive tumor microenvironment restrains the activity of the effector immune cells. Therefore, systematic immunomodulation is critical to stimulate the tumor microenvironment and augment the anti-tumor therapeutic effect. To this end, polyethylene glycol (PEG)-stabilized platinum (Pt) nanoparticles (Pt NPs) conjugated with a PD-L1 inhibitor (BMS-1) through a thermo-sensitive linkage were constructed. Upon near-infrared (NIR) exposure, BMS-1 was released and maleimide (Mal) was exposed on the surface of Pt NPs, which captured the antigens released from the ablated tumor cells, resulting in the enhanced antigen internalization and presentation. In addition, the Pt NPs acted as immune adjuvants by stimulating dendritic cells (DCs) maturation. Furthermore, BMS-1 relieved T cell exhaustion and induced the infiltration of effector T cells into the tumor tissues. Thus, Pt NPs can ablate tumors through PTT, and augment the anti-tumor immune response through enhanced antigen presentation and T cells infiltration, thereby preventing tumor relapse and metastasis.

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Pt NPs ablated tumor cells through PTT and served as immune adjuvants.

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Released BMS-1 and deprotected maleimide by thermo-sensitive Diels-Alder reaction.

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Pt NPs captured the antigens with exposed maleimide and stimulated dendritic cells maturation.

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Controlled release of BMS-1 in response to PTT relieved T cell exhaustion.

Injectable hydrogel-mediated combination of hyperthermia ablation and photo-enhanced chemotherapy in the NIR-II window for tumor eradication

Local administration of therapeutic agents with long-term retention capabilities efficiently avoids nonspecific distribution in normal organs with an increased drug concentration in pathological tissue. Herein, we developed an injectable and degradable alginate-calcium (Ca2+) hydrogel for the local administration of corn-like Au/Ag nanorods (NRs) and doxorubicin hydrochloride (DOX·HCl). The immobilized Au/Ag NRs with strong absorbance in the near-infrared II (NIR-II) window efficiently ablated the majority of tumor cells after 1064 nm laser irradiation and triggered the release of DOX to kill residual tumor cells. As a result, injectable hydrogel-mediated NIR-II photothermal therapy (PTT) and chemotherapy efficiently inhibited tumor growth, resulting in the complete eradication of tumors in most of the treated mice. Furthermore, owing to the confinement of the Au/Ag NRs and DOX·HCl within the hydrogel, such treatment exhibited excellent biocompatibility.

Cancer cell membrane-coated gold nanorods for photothermal therapy and radiotherapy on oral squamous cancer

The combination of different modalities greatly enhances the anticancer efficacy of each treatment by combining their merits, showing promising potential in clinical translation. Herein, we fabricated cancer cell membrane-coated gold nanorods (GNR@Mem) possessing excellent photothermal transfer ability in the second near-infrared window and radiosensitizing ability under X-ray irradiation. The cancer cell membrane coating endowed the nanomedicine with stability in the physiological environment and selective homotypic targeting to specific cancer cells in vitro. Under NIR light and X-ray irradiation, the gold nanorods induced a temperature increase, reactive oxygen generation, and subsequent damage to the DNA helix structure, leading to enhanced cell apoptosis. Benefitting from its relative long circulation time in the blood and homotypic targeting effect, the tumor accumulation of GNR@Mem significantly increased. The in vivo results demonstrate that the combination of photothermal therapy and radiotherapy effectively suppresses tumor growth without noticeable systemic toxicity.

Noble Metal Nanomaterials for NIR-Triggered Photothermal Therapy in Cancer

It is of great significance to develop anticancer therapeutic agents or technologies with high degree of specificity and patient compliance, while low toxicity. The emerging photothermal therapy (PTT) has become a new and powerful therapeutic technology due to its noninvasiveness, high specificity, low side effects to normal tissues and strong anticancer efficacy. Noble metal nanomaterials possess strong surface plasmon resonance (SPR) effect and synthetic tunability, which make them facile and effective PTT agents with superior optical and photothermal characteristics, such as high absorption cross-section, incomparable optical-thermal conversion efficiency in the near infrared (NIR) region, as well as the potential of bioimaging. By incorporating with various functional reagents such as antibodies, peptides, biocompatible polymers, chemo-drug and immune factors, noble metal nanomaterials have presented strong potential in multifunctional cancer therapy. Herein, the recent development regarding the application of noble metal nanomaterials for NIR-triggered PTT in cancer treatment is summarized. A variety of studies with good therapeutic effects against cancer from impressive photothermal efficacy of noble metal nanomaterials are concluded. Intelligent nanoplatforms through ingenious fabrication showing potential of multifunctional PTT, combined with chemo-therapy, immunotherapy, photodynamic therapy (PDT), as well as simultaneous imaging modality are also demonstrated.

Improving the photothermal therapy efficacy and preventing the surface oxidation of bismuth nanoparticles through the formation of a bismuth@bismuth selenide heterostructure

Bismuth (Bi) nanoparticles (NPs) are emerging as promising photothermal agents for computed tomography imaging-guided photothermal therapy. However, it is challenging to improve their photothermal conversion efficacy and prevent their oxidation. Herein, Bi@bismuth selenide (Bi2Se3) core@shell NPs were designed and fabricated for improving the photothermal performance due to the staggered energy levels between Bi and Bi2Se3. With near-infrared light irradiation, both the materials could be excited to generate hot carriers due to their extremely narrow bandgaps. The hot electrons would transfer to the conduction band of Bi2Se3 and the hot holes to the valence band of Bi, leading to the effective separation of hot carriers. Then, these hot electrons and holes would recombine nonradiatively at the interface of Bi and Bi2Se3 and produce more phonons, resulting in an enhanced photothermal conversion efficacy. Moreover, the presence of Bi2Se3 on the surface of Bi NPs could prevent Bi from surface oxidation due to the higher stability of Bi2Se3. In fact, Bi@Bi2Se3 NPs showed excellent biocompatibility and photothermal therapeutic efficacy against cancer cells.

Artificial Organelles Based on Cross-Linked Zwitterionic Vesicles

Artificial organelles (AOs) are typical microcompartments with intracellular biocatalytic activity aimed to replace missing or lost cellular functions. Currently, liposomes or polymersomes are popular microcompartments to build AOs by embedding channel proteins in their hydrophobic domain and entrapping natural enzymes in their cavity. Herein, a new microcompartment is established by using monolayer cross-linked zwitterionic vesicles (cZVs) with a carboxylic acid saturated cavity. The monolayer structure endows the cZVs with intrinsic permeability; the cavity supplies the cZVs ability of in situ synthesis of artificial enzymes, and the pH-dependent charge-change property makes it possible to overcome the biological barriers. Typically, nanozymes of CeO₂ and Pt NPs were synthesized in the cZVs to mimic peroxisome. In vitro experiments confirmed that the resulting artificial peroxisome (AP) could resist protein adsorption, endocytose efficiently, and escape from the lysosome. In vivo experiments demonstrated that the APs held a good therapeutic effect in ROS-induced ear-inflammation.

Flexible Pt3Ni-S-Deposited Teflon Membrane with High Surface Mechanical Properties for Efficient Solar-Driven Strong Acidic/Alkaline Water Evaporation

Solar-driven water evaporation provides a promising solution to the energy crisis and environmental issues. Capitalizing on the high photothermal conversion efficiency and excellent resistance to strong acids or strong alkalis of Pt₃Ni-S nanowires, we strategically design and prepare a flexible Pt₃Ni-S-deposited Teflon (PTFE) membrane for achieving efficient strong acid/alkaline water evaporation under simulated sunlight irradiation (1 sun). By comparing the surface morphology, mechanical properties, and water evaporation performance of the as-prepared three different membranes, we have screened out a high-performance photothermal membrane that has good hydrophobicity (water contact angle = 106°), strong mechanical properties, high light-to-heat conversion efficiency (η = 80%), and excellent durability (10 cycles in a range of pH = 1.2-12). In particular, we explore the mechanism of high surface mechanical properties of the as-prepared membrane using density functional theory. The results demonstrate that the related mechanism can be ascribed to two main reasons: (1) hydrogen bonds can be formed between the 2-pyrrolidone ring and PTFE-3 and (2) the O atom in PTFE-3 carries more negative charge (-0.19 |e|) than PTFE-1 (-0.16 |e|) and PTFE-2 (-0.15 |e|). Our work highlights the great potentials of a Pt₃Ni-S-deposited PTFE membrane as a device for implementing solar energy-driven evaporation of industrial wastewater with strong acidity or alkalinity and provides a new strategy for improving the surface mechanical properties of a photothermal membrane.

Ultrasmall Rhodium Nanozyme with RONS Scavenging and Photothermal Activities for Anti-Inflammation and Antitumor Theranostics of Colon Diseases

Colitis-associated colorectal cancer (CAC), in which chronic inflammation is a well-recognized carcinogen, requires concurrent anti-inflammation and antitumor treatments in the clinic. Herein, we report polyethylene glycol (PEG)-coated (PEGylated) ultrasmall rhodium nanodots (Rh-PEG NDs) can serve as a metallic nanozyme with reactive oxygen and nitrogen species (RONS) scavenging properties as well as photothermal activities for anti-inflammation and antitumor theranostics in colon diseases. Benefiting from multienzyme activities against RONS, Rh-PEG NDs can decrease the levels of pro-inflammatory cytokines (TNF-α, IL-6), resulting in good anti-inflammatory effect on dextran sulfate sodium-induced colitis. By virtue of high photothermal conversion efficiency (48.9%), Rh-PEG NDs demonstrate complete ablation of CT-26 colon tumor without any recurrence. Most importantly, Rh-PEG NDs exhibit good biocompatibility both at the cellular and animal levels. Our findings provide a paradigm to utilize metallic nanozymes for the potential management of colon diseases.

A nano-based thermotherapy for cancer stem cell-targeted therapy

Cancer stem cells (CSCs) exhibit high resistance to conventional therapy and are responsible for cancer metastasis and tumor relapse.