PEGylated Micelle Nanoparticles Encapsulating a Non‐Fluorescent Near‐Infrared Organic Dye as a Safe and Highly‐Effective Photothermal Agent for In Vivo Cancer Therapy

Photothermal therapy (PTT), as a minimally invasive and highly effective cancer treatment approach, has received widespread attention in recent years. Tremendous effort has been devoted to explore various types of photothermal agents with high near‐infrared (NIR) absorbance for PTT cancer treatment. Despite many exciting progresses in the area, effective yet safe photothermal agents with good biocompatibility and biodegradability are still highly desired. In this work, a new organic PTT agent based on polyethylene glycol (PEG) coated micelle nanoparticles encapsulating a heptamethine indocyanine dye IR825 is developed, showing a strong NIR absorption band and a rather low quantum yield, for in vivo photothermal treatment of cancer. It is found that the IR825–PEG nanoparticles show ultra‐high in vivo tumor uptake after intravenous injection, and appear to be an excellent PTT agent for tumor ablation under a low‐power laser irradiation, without rendering any appreciable toxicity to the treated animals. Compared with inorganic nanomaterials and conjugated polymers being explored in PTT, the NIR‐absorbing micelle nanoparticles presented here may have the least safety concern while showing excellent treatment efficacy, and thus may be a new photothermal agent potentially useful in clinical applications.     

pH‐Responsive Cyanine‐Grafted Graphene Oxide for Fluorescence Resonance Energy Transfer‐Enhanced Photothermal Therapy

Stimuli‐responsive anticancer agents are of particular interest in the field of cancer therapy. Nevertheless, so far stimuli‐responsive photothermal agents have been explored with limited success for cancer photothermal therapy (PTT). In this work, as a proof‐of‐concept, a pH‐responsive photothermal nanoconjugate for enhanced PTT efficacy, in which graphene oxide (GO) with broad NIR absorbance and effective photothermal conversion efficiency is selected as a typical model receptor of fluorescence resonance energy transfer (FRET), and grafted cyanine dye (e.g., Cypate) acts as the donor of near‐infrared fluorescence (NIRF), is reported for the first time. The conjugate of Cypate‐grafted GO exhibits different conformations in aqueous solutions at various pH, which can trigger pH‐dependent FRET effect between GO and Cypate and thus induce pH‐responsive photothermal effect of GO‐Cypate. GO‐Cypate exhibits severe cell damage owing to the enhanced photothermal effect in lysosomes, and thus generate synergistic PTT efficacy with tumor ablation upon photoirradiation after a single‐dose intravenous injection. The photothermal nanoconjugate with broad NIR absorbance as the effective receptor of FRET can smartly convert emitted NIRF energy from donor cyanine dye into additional photothermal effect for improving PTT. These results suggest that the smart nanoconjugate can act as a promising stimuli‐responsive photothermal nanoplatform for cancer therapy.     

Near‐Infrared Laser‐Triggered Nitric Oxide Nanogenerators for the Reversal of Multidrug Resistance in Cancer

The potential therapeutic implications of nitric oxide (NO) for diverse diseases have been under consideration for years; however, the development of precisely controllable NO generation system with potential for clinical application has remained elusive. Herein, intelligent near‐infrared (NIR) laser‐triggered NO nanogenerators for the treatment of multidrug‐resistant (MDR) cancer are fabricated by integrating photothermal agents and heat‐sensitive NO donors into a single nanoparticle. Such nanogenerators can absorb 808 nm NIR photons and convert them into ample heat to trigger NO release. The generated NO molecules are demonstrated to successfully achieve multidrug‐resistance reversal by inhibiting the expression of P‐glycol protein. Consequently, the intracellular accumulation of doxorubicin is effectively increased, resulting in high toxicity to MDR cancer cells in vitro. By virtue of surface modification with targeting ligands, these nanoparticles are able to selectively accumulate in tumor tissue. The therapeutic effects of the nanogenerators are validated in a humanized MDR cancer model. The in vivo experiment indicates that the nanoparticles possess excellent tumor suppression functionality with few side effects upon NIR laser exposure. Therefore, this novel photothermal conversion‐based NO‐releasing platform is expected to be a potential alternative to clinical MDR cancer treatment and may provide insights with regard to other NO‐relevant medical treatments.     

Cisplatin‐Prodrug‐Constructed Liposomes as a Versatile Theranostic Nanoplatform for Bimodal Imaging Guided Combination Cancer Therapy

Up to date, a large variety of liposomal nanodrugs have been explored for cancer nanomedicine, showing encouraging results in both preclinical animal experiments and clinical treatment of cancer patients. Herein, a phospholipid conjugated with a cisplatin prodrug is used as the major structure component of liposomes together with other commercial lipids via self‐assembling. By doping with 1,1′‐dioctadecyl‐3,3,3′,3′‐tetramethylindotricarbocyanine iodide (DiR), a lipophilic dye with strong near infrared (NIR) absorbance and fluorescence, the obtained DiR‐Pt(IV)‐liposome is found to be an effective probe for in vivo NIR fluorescence and photoacoustic bimodal imaging. Attributing to its intrinsically doped cis‐Pt(IV) prodrug, efficient photothermal conversion ability, and excellent tumor homing ability, DiR‐Pt(IV)‐liposome confers greatly enhanced therapeutic outcomes in the combined photothermal‐chemotherapy. Moreover, Pt(IV)‐liposome is also demonstrated to be an efficient carrier for both small hydrophilic molecules and proteins, which are encapsulated inside the water‐cavity of liposomes, further demonstrating the versatile functions of this nanoplatform. This study develops a unique type of liposomal nanomedicine with a prodrug conjugated phospholipid as the major structure component. Such Pt(IV)‐liposome is featured with advantages including precisely defined/easily tunable drug compositions, stealth‐like pharmacokinetics, efficient tumor passive uptake, and the capabilities to simultaneously load with various types of imaging or therapeutic agents.     

Photo‐ and pH‐Triggered Release of Anticancer Drugs from Mesoporous Silica‐Coated Pd@Ag Nanoparticles

A smart drug delivery system integrating both photothermal therapy and chemotherapy for killing cancer cells is reported. The delivery system is based on a mesoporous silica‐coated Pd@Ag nanoplates composite. The Pd@Ag nanoplate core can effectively absorb and convert near infrared (NIR) light into heat. The mesoporous silica shell is provided as the host for loading anticancer drug, doxorubicin (DOX). The mesoporous shell consists of large pores, ～10 nm in diameter, and allows the DOX loading as high as 49% in weight. DOX loaded core–shell nanoparticles exhibit a higher efficiency in killing cancer cells than free DOX. More importantly, DOX molecules are loaded in the mesopores shell through coordination bonds that are responsive to pH and heat. The release of DOX from the core‐shell delivery vehicles into cancer cells can be therefore triggered by the pH drop caused by endocytosis and also NIR irradiation. A synergistic effect of combining chemotherapy and photothermal therapy is observed in our core‐shell drug delivery system. The cell‐killing efficacy by DOX‐loaded core–shell particles under NIR irradiation is higher than the sum of chemotherapy by DOX‐loaded particles and photothermal therapy by core–shell particles without DOX.     

Light‐Activatable Assembled Nanoparticles to Improve Tumor Penetration and Eradicate Metastasis in Triple Negative Breast Cancer

Triple‐negative breast cancer (TNBC) is a kind of aggressive malignancy with fast metastatic behavior. Herein, a nanosystem loaded with a near‐infrared (NIR) agent is developed to achieve chemo‐photothermal combination therapy for inhibiting tumor growth and metastasis in TNBC. The NIR agent of ultrasmall sized copper sulfide nanodots with strong NIR light‐absorbing capability is entrapped into the doxorubicin‐contained temperature‐sensitive polymer‐based nanosystem by a self‐assembled method. The temperature sensitive nanoclusters (TSNCs) can significantly enhance the drug penetration depth and significantly kill the cancer cells under the near‐infrared laser irradiation. Importantly, it is plausible that the tumor penetrating nanosystem combined with NIR laser irradiation can prevent lung and liver metastasis via extermination of the cancer stem cells. The in vivo characteristics, evaluated by photoacoustic imaging, pharmacokinetics, and biodistribution, confirm their feasibility for tumor treatment owing to their long blood circulation time and high tumor uptake. Thanks to the high tumor uptake and highly potent antitumor efficacy, the doxorubicin‐induced cardiotoxicity can be avoided when the TSNC is used. Taken together, it is believed that the nanosystem has excellent potential for clinical translation.     

NIR‐Activated Supersensitive Drug Release Using Nanoparticles with a Flow Core

Near infrared (NIR) light‐activated supersensitive drug release via photothermal conversion is of particular interest due to its advantages in spatial and temporal control. However, such supersensitive drug release is rarely reported for polymeric nanoparticles. In this study, polymeric nanoparticles observed with flowable core can achieve NIR‐activated supersensitive drug release under the assistance of photothermal agent. It is demonstrated that only 5 s NIR irradiation (808 nm, 0.3 W cm^?2) leads to 17.8% of doxorubicin (DOX) release, while its release is almost completely stopped when the NIR laser is switched off. In contrast, the control, poly(d ,l ‐lactide) nanoparticles with rigid cores, do not exhibit such supersensitive effect. It is demonstrated that intraparticle temperature is notably increased during photothermal conversion by detecting fluorescein lifetime using a time‐correlated single photon counting (TCSPC) technique, which is the main driving force for such supersensitive drug release from hydrophobic flow core. In contrast, rigid chain of nanoparticular core hinders drug diffusion. Furthermore, such NIR light‐activated supersensitive drug release is demonstrated, which significantly enhances its anticancer efficacy, resulting in overcoming of the resistance of cancer cells against DOX treatment in vitro and in vivo. This simple and highly universal strategy provides a new approach to fabricate NIR light‐activated supersensitive drug delivery systems.     

Tantalum Sulfide Nanosheets as a Theranostic Nanoplatform for Computed Tomography Imaging‐Guided Combinatorial Chemo‐Photothermal Therapy

Near‐infrared (NIR)‐absorbing metal‐based nanomaterials have shown tremendous potential for cancer therapy, given their facile and controllable synthesis, efficient photothermal conversion, capability of spatiotemporal‐controlled drug delivery, and intrinsic imaging function. Tantalum (Ta) is among the most biocompatible metals and arouses negligible adverse biological responses in either oxidized or reduced forms, and thus Ta‐derived nanomaterials represent promising candidates for biomedical applications. However, Ta‐based nanomaterials by themselves have not been explored for NIR‐mediated photothermal ablation therapy. In this work, an innovative Ta‐based multifunctional nanoplatform composed of biocompatible tantalum sulfide (TaS₂) nanosheets (NSs) is reported for simultaneous NIR hyperthermia, drug delivery, and computed tomography (CT) imaging. The TaS₂ NSs exhibit multiple unique features including (i) efficient NIR light‐to‐heat conversion with a high photothermal conversion efficiency of 39%, (ii) high drug loading (177% by weight), (iii) controlled drug release triggered by NIR light and moderate acidic pH, (iv) high tumor accumulation via heat‐enhanced tumor vascular permeability, (v) complete tumor ablation and negligible side effects, and (vi) comparable CT imaging contrast efficiency to the widely clinically used agent iobitridol. It is expected that this multifunctional NS platform can serve as a promising candidate for imaging‐guided cancer therapy and selection of cancer patients with high tumor accumulation.     

Enhanced Antitumor Efficacy by 808 nm Laser‐Induced Synergistic Photothermal and Photodynamic Therapy Based on a Indocyanine‐Green‐Attached W18O49 Nanostructure

A novel nanoplatform based on tungsten oxide (W₁₈O₄₉, WO) and indocyanine green (ICG) for dual‐modal photothermal therapy (PTT) and photodynamic therapy (PDT) has been successfully constructed. In this design, the hierarchical unique nanorod‐bundled W₁₈O₄₉ nanostructures play roles in being not only as an efficient photothermal agent for PTT but also as a potential nanovehicle for ICG molecules via electrostatic adsorption after modified with trimethylammonium groups on their surface. It is found that the ability of ICG to produce cytotoxic reactive oxygen species for PDT is well maintained after being attached on the WO, thus the as‐obtained WO@ICG can achieve a synergistic effect of combined PTT and PDT under single 808 nm near‐infrared (NIR) laser excitation. Notably, compared with PTT or PDT alone, the enhanced HeLa cells lethality of the 808 nm laser triggered dual‐modal therapy is observed. The in vivo animal experiments have shown that WO@ICG has effective solid tumor ablation effect with 808 nm NIR light irradiation, revealing the potential of these nanocomposites as a NIR‐mediated dual‐modal therapeutic platform for cancer treatment.     

Engineering of Multifunctional Nano‐Micelles for Combined Photothermal and Photodynamic Therapy Under the Guidance of Multimodal Imaging

The integration of diagnostic and therapeutic functionalities on a single theranostic nano‐system holds great promise to enhance the accuracy of diagnosis and improve the efficacy of therapy. Herein, a multifunctional polymeric nano‐micelle system that contains a photosensitizer chlorin e6 (Ce6) is successfully fabricated, at the same time serving as a chelating agent for Gd³⁺, together with a near‐infrared (NIR) dye, IR825. With a r₁ relativity 7 times higher than that of the commercial agent Magnevist, strong fluorescence offered by Ce6, and high NIR absorbance attributed to IR825, these theranostic micelles can be utilized as a contrast agent for triple modal magnetic resonance (MR), fluorescence, and photoacoustic imaging of tumors in a mouse model. The combined photothermal and photodynamic therapy is then carried out, achieving a synergistic anti‐tumor effect both in vitro and in vivo. Different from single photo treatment modalities which only affect the superficial region of the tumor under mild doses, the combination therapy at the same dose using this agent is able to induce significant damage to both superficial and deep parts of the tumor. Therefore, this work presents a polymer based theranostic platform with great potential in multimodal imaging and combination therapy of cancer.     

Photoresponsive Protein–Graphene–Protein Hybrid Capsules with Dual Targeted Heat‐Triggered Drug Delivery Approach for Enhanced Tumor Therapy

A novel photo‐responsive protein–graphene–protein (PGP) capsule that doubles as a photothermal agent with core/shell structure is constructed by anchoring reduced graphene oxide nanosheets on one‐component protein (lactoferrin) shell through a double emulsion method. PGP capsules can transport fully concealed hydrophilic anticancer cargo, doxorubicin (Dox), with a large payload (9.43 μmol g^‐1) to be later unloaded in a burst‐like manner by photo‐actuation triggered by near‐infrared irradiation. Being biocompatible yet with a high cancer cell targeting efficiency, PGP capsules have successfully eradicated subcutaneous tumors in 10 d following a single 5 min NIR irradiation without distal damage. Besides, the photochemothermal therapy of PGP capsules eradicates tumor cells not only in the light‐treating area but also widely light‐omitted tumor cells, overcoming the tumor recurrence due to efficient cell killing efficacy. These results demonstrate that the PGP capsule is a potential new drug delivery platform for local‐targeting, on‐demand, photoresponsive, combined chemotherapy/hyperthermia for tumor treatment and other biomedical applications.     

Self‐Assembled/Drug‐Composed Nanomedicine for Synergistic Photonic Hyperthermia and Targeted Therapy of Breast Cancer by Inhibiting ERK,AKT, and STAT3 Signaling Cascades

Superior to chemotherapy, photonic hyperthermia and targeted therapy have made attractive impacts on cancer treatment by virtue of their profound advantages such as high specificity and minimal invasiveness, but the rational integration of corresponding therapeutic drugs for achieving concurrent photothermal ablation/targeted therapy is still challenging. Herein, a self‐assembled nanomedicine Anlotinib@IR820 is constructed with drug formulations for highly efficient and synergistic photonic hyperthermia and targeted therapy against breast cancer. Specifically, the constructed Anlotinib@IR820 nanomedicine presents high accumulation at the tumor site owing to the enhanced permeability and retention effect and simultaneously overcomes the obstacles of poor water solubility of Anlotinib (for targeted therapy) and the short lifetime of IR820 (for photonic ablation). The photothermal ablation as activated by near‐infrared laser can not only irradiate cancer cells but also promote the cellular uptake of Anlotinib, which presents a profound synergistic function both in vitro and in vivo. Mechanically, Anlotinib@IR820 nanomedicine can induce apoptosis and cause cell cycle arrest in breast cancer through inhibiting ERK, AKT, and STAT3 pathways. Therefore, the rationally designed drug‐composed Anlotinib@IR820 nanomedicine exhibits high clinical translation potential because of its therapeutic nanoformulation, which provides an alternative option for efficient combinational therapy of breast cancer.     

NIR Light‐Triggered Degradable MoTe2 Nanosheets for Combined Photothermal and Chemotherapy of Cancer

Telluride molybdenum (MoTe₂) nanosheets with wide near‐infrared (NIR) absorbance are functionalized with polyethylene glycol‐cyclic arginine‐glycine‐aspartic acid tripeptide (PEG‐cRGD). After loading a chemotherapeutic drug (doxorubicin, DOX), MoTe₂‐PEG‐cRGD/DOX is used for combined photothermal therapy and chemotherapy. With the high photothermal conversion efficiency, MoTe₂‐PEG‐cRGD/DOX exhibits favorable cells killing ability under NIR irradiation. Owing to the cRGD‐mediated specific tumor targeting, MoTe₂‐PEG‐cRGD/DOX shows efficient accumulation in tumors to induce a strong tumor ablation effect. MoTe₂‐PEG‐cRGD nanosheets, which are relatively stable in the circulation, could be degraded under NIR ray. The in vitro and in vivo experimental results demonstrate that this theranostic nanoagent, which could accumulate in tumors to allow photothermal imaging and combined therapy, is readily degradable in normal organs to enable rapid excretion and avoid long‐term retention/toxicity, holding great potential to treat tumor effectively.     

SnTe@MnO2‐SP Nanosheet–Based Intelligent Nanoplatform for Second Near‐Infrared Light–Mediated Cancer Theranostics

Near infrared light, especially the second near‐infrared light (NIR II) biowindows with deep penetration and high sensitivity are widely used for optical diagnosis and phototherapy. Here, a novel kind of 2D SnTe@MnO₂‐SP nanosheet (NS)‐based nanoplatform is developed for cancer theranostics with NIR II‐mediated precise optical imaging and effective photothermal ablation of mouse xenografted tumors. The 2D SnTe@MnO₂‐SP NSs are fabricated via a facile method combining ball‐milling and liquid exfoliation for synthesis of SnTe NSs, and surface coating MnO₂ shell and soybean phospholipid (SP). The ultrathin SnTe@MnO₂‐SP NSs reveal notably high photothermal conversion efficiency (38.2% in NIR I and 43.9% in NIR II). The SnTe@MnO₂‐SP NSs inherently feature tumor microenvironment (TME)‐responsive biodegradability, and the main metabolite TeO₃^2? shows great antitumor effect, coupling synergetic chemotherapy for cancer. Moreover, the SnTe@MnO₂‐SP NSs also exhibit great potential for fluorescence, photoacoustic (PA), and photothermal imaging agents in the NIR II biowindow with much higher resolution and sensitivity. This is the first report, as far as is known, with such an inorganic nanoagent setting fluorescence/PA/photothermal imaging and photothermal therapy in NIR II biowindow and TME‐responsive biodegradability rolled into one, which provide insight into the clinical potential for cancer theranostics.     

Doxorubicin‐Loaded Single Wall Nanotube Thermo‐Sensitive Hydrogel for Gastric Cancer Chemo‐Photothermal Therapy

Single wall carbon nanotube (SWNT) based thermo‐sensitive hydrogel (SWNT‐GEL) is reported, which provides an injectable drug delivery system as well as a medium for photothermal transduction. SWNT‐hydrogel alone appears to be nontoxic on gastric cancer cells (BGC‐823 cell line) but leads to cell death with NIR radiation through a hyperthermia proapoptosis mechanism. By incorporating hyperthermia therapy and controlled in situ doxorubicin (DOX) release, DOX‐loaded SWNT‐hydrogel with NIR radiation proves higher tumor suppression rate on mice xenograft gastric tumor models compared to free DOX without detectable organ toxicity. The developed system demonstrates improved efficacy of chemotherapeutic drugs which overcomes systemic adverse reactions and presents immense potential for gastric cancer treatment.     

A Low‐Toxic Multifunctional Nanoplatform Based on Cu9S5@mSiO2 Core‐Shell Nanocomposites: Combining Photothermal‐ and Chemotherapies with Infrared Thermal Imaging for Cancer Treatment

Copper chalcogenides have been demonstrated to be a promising photothermal agent due to their high photothermal conversion efficiency, synthetic simplicity, and low cost. However, the hydrophobic and less biocompatible characteristics associated with their synthetic processes hamper widely biological applications. An alternative strategy for improving hydrophilicity and biocompatibility is to coat the copper chalcogenide nanomaterials with silica shell. Herein, the rational preparation design results in successful coating mesoporous silica (mSiO₂) on as‐synthesized Cu₉S₅ nanocrystals, forming Cu₉S₅@mSiO₂‐PEG core‐shell nanostructures. As‐prepared Cu₉S₅@mSiO₂‐PEG core‐shell nanostructures show low cytotoxicity and excellent blood compatibility, and are effectively employed for photothermal ablation of cancer cells and infrared thermal imaging. Moreover, anticancer drug of doxorubicin (DOX)‐loaded Cu₉S₅@mSiO₂‐PEG core‐shell nanostructures show pH sensitive release profile and are therefore beneficial to delivery of DOX into cancer cells for chemotherapy. Importantly, the combination of photothermal‐ and chemotherapies demonstrates better effects of therapy on cancer treatment than individual therapy approaches in vitro and in vivo.     

Remotely Controlled Red Blood Cell Carriers for Cancer Targeting and Near‐Infrared Light‐Triggered Drug Release in Combined Photothermal–Chemotherapy

Red blood cells (RBCs), the “innate carriers” in blood vessels, are gifted with many unique advantages in drug transportation over synthetic drug delivery systems (DDSs). Herein, a tumor angiogenesis targeting, light stimulus‐responsive, RBC‐based DDS is developed by incorporating various functional components within the RBC platform. An albumin bound near‐infrared (NIR) dye, together with a chemotherapy drug doxorubicin, is encapsulated inside RBCs, the surfaces of which are modified with a targeting peptide to allow cancer targeting. Under stimulation by an external NIR laser, the membrane of the RBCs would be destroyed by the light‐induced photothermal heating, resulting in effective drug release. As a proof of principle, RBC‐based cancer cell targeted drug delivery and light‐controlled drug release is demonstrated in vitro, achieving a marked synergistic therapeutic effect through the combined photothermal–chemotherapy. This work presents a novel design of smart RBC carriers, which are inherently biocompatible, promising for targeted combination therapy of cancer.     

High‐Yield Synthesis of Multifunctional Tellurium Nanorods to Achieve Simultaneous Chemo‐Photothermal Combination Cancer Therapy

Tellurium (Te) is an important semiconductor material with low band‐gap energy, which has attracted considerable attention in recent years, due to its special chemical and physical properties and wide potential in electrochemistry, optoelectronics, and biological fields. This study demonstrates a facile and high‐yield synthesis strategy of Te nanorods (PTW‐TeNRs) decorated by polysaccharide–protein complex, which can achieve simultaneous chemo‐photothermal combination therapy against cancers. PTW‐TeNRs alone possess high stability under physiological conditions, potent anticancer activities through induction of reactive oxygen species overproduction, and high selectivity among tumor and normal cells. More importantly, they exhibit strong near‐infrared (NIR) absorbance and good photothermal conversion ability from NIR light to heat energy. Furthermore, in combination with NIR laser irradiation, PTW‐TeNRs exhibit excellent chemo‐photothermal efficiency and low toxicity as evidenced by highly efficient tumor ablation ability, but show no obvious histological damage to the major organs. Taken together, this study provides a valid tactic for facile synthesis of multifunctional tellurium nanorods for efficient and combinational cancer therapy.     

Tumor‐Penetrating Nanotherapeutics Loading a Near‐Infrared Probe Inhibit Growth and Metastasis of Breast Cancer

The tumor growth and metastasis is the leading reason for the high mortality of breast cancer. Herein, it is first reported a deep tumor‐penetrating photothermal nanotherapeutics loading a near‐infrared (NIR) probe for potential photothermal therapy (PTT) of tumor growth and metastasis of breast cancer. The NIR probe of 1,1‐dioctadecyl‐3,3,3,3‐tetramethylindotricarbocyanine iodide (DiR), a lipophilicfluorescent carbocyanine dye with strong light‐absorbing capability, is entrapped into the photothermal nanotherapeutics for PTT application. The DiR‐loaded photothermal nanotherapeutics (DPN) is homogeneous nanometer‐sized particles with the mean diameter of 24.5 ± 4.1 nm. Upon 808 nm laser irradiation, DPN presents superior production of thermal energy than free DiR both in vitro and in vivo. The cell proliferation and migration activities of metastatic 4T1 breast cancer cells are obviously inhibited by DPN in combination with NIR irradiation. Moreover, DPN can induce a higher accumulation in tumor and penetrate into the deep interior of tumor tissues. The in vivo PTT measurements indicate that the growth and metastasis of breast cancer are entirely inhibited by a single treatment of DPN with NIR irradiation. Therefore, the deep tumor‐penetrating DPN can provide a promising strategy for PTT of tumor progression and metastasis of breast cancer.     

Gold Nanoshell Nanomicelles for Potential Magnetic Resonance Imaging,Light‐Triggered Drug Release,and Photothermal Therapy

A novel multifunctional drug‐delivery platform is developed based on cholesteryl succinyl silane (CSS) nanomicelles loaded with doxorubicin, Fe₃O₄ magnetic nanoparticles, and gold nanoshells (CDF‐Au‐shell nanomicelles) to combine magnetic resonance (MR) imaging, magnetic‐targeted drug delivery, light‐triggered drug release, and photothermal therapy. The nanomicelles show improved drug‐encapsulation efficiency and loading level, and a good response to magnetic fields, even after the formation of the gold nanoshell. An enhancement for T₂‐weighted MR imaging is observed for the CDF‐Au‐shell nanomicelles. These nanomicelles display surface plasmon absorbance in the near‐infrared (NIR) region, thus exhibiting an NIR (808 nm)‐induced temperature elevation and an NIR light‐triggered and stepwise release behavior of doxorubicin due to the unique characteristics of the CSS nanomicelles. Photothermal cytotoxicity in vitro confirms that the CDF‐Au‐shell nanomicelles cause cell death through photothermal effects only under NIR laser irradiation. Cancer cells incubated with CDF‐Au‐shell nanomicelles show a significant decrease in cell viability only in the presence of both NIR irradiation and a magnetic field, which is attributed to the synergetic effects of the magnetic‐field‐guided drug delivery and the photothermal therapy. Therefore, such multicomponent nanomicelles can be developed as a smart and promising nanosystem that integrates multiple capabilities for effective cancer diagnosis and therapy.