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.     

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.     

Near‐Infrared Light‐Absorptive Stealth Liposomes for Localized Photothermal Ablation of Tumors Combined with Chemotherapy

Although near‐infrared (NIR) light‐absorbing organic dyes have recently been proposed for photothermal ablation of tumors, their clinical applications have often been hampered by problems such as low water solubility and minimal tissue absorption. Rapid development of nanotechnology provides various novel nanostructures to address these issues. In this work, doxorubicin (DOX)‐loaded stealth liposomes are engineered through the incorporation of an NIR‐absorptive heptamethine indocyanine dye IR825 into the thermoresponsive liposomes for photothermal/chemo combined cancer therapy. It is demonstrated that the lipid nanostructure can enhance the bioavailability of water‐insoluble IR825 for efficient photothermal treatment, while delivering the anticancer drug doxorubicin to achieve simultaneous anticancer medication. The combined treatment of photothermal ablation and chemotherapy synergistically improves the overall cancer cell killing efficiency, which can be of future clinical interest.     

Gold Nanoframeworks with Mesopores for Raman–Photoacoustic Imaging and Photo‐Chemo Tumor Therapy in the Second Near‐Infrared Biowindow

Gold‐based nanostructures with tunable wavelength of localized surface plasmon resonance (LSPR) in the second near‐infrared (NIR‐II) biowindow receive increasing attention in phototheranostics. In view of limited progress on NIR‐II gold nanostructures, a particular liposome template‐guided route is explored to synthesize novel gold nanoframeworks (AuNFs) with large mesopores (≈40 nm) for multimodal imaging along with therapeutic robustness. The synthesized AuNFs exhibit strong absorbance in NIR‐II region, affording their capacity of NIR‐II photothermal therapy (PTT) and photoacoustic (PA) imaging for deep tumors. Functionalization of AuNFs with hyaluronic acid (HA) endows the targeting capacity for CD44‐overexpressed tumor cells while gatekeeping doxorubicin (DOX) loaded into mesopores. Conjugation of Raman reporter 4‐aminothiophenol (4‐ATP) onto AuNFs yields a surface‐enhanced Raman scattering (SERS) fingerprint for Raman spectroscopy/imaging. In vivo evaluation of HA‐4‐ATP‐AuNFs‐DOX on tumor‐bearing xenografts demonstrates its high efficacy in eradication of solid tumors in NIR‐II under PA–Raman dual image‐guided photo‐chemotherapy. Thus, current AuNFs offer versatile capabilities for phototheranostics.     

Ultrasmall Semiconducting Polymer Dots with Rapid Clearance for Second Near‐Infrared Photoacoustic Imaging and Photothermal Cancer Therapy

Phototheranostic agents in the second near‐infrared (NIR‐II) window (1000–1700 nm) are emerging as a promising theranostic platform for precision medicine due to enhanced penetration depth and minimized tissue exposure. The development of metabolizable NIR‐II nanoagents for imaging‐guided therapy are essential for noninvasive disease diagnosis and precise ablation of tumors. Herein, metabolizable highly absorbing NIR‐II conjugated polymer dots (Pdots) are reported for the first time for photoacoustic imaging guided photothermal therapy (PTT). The unique design of low‐bandgap D‐A π‐conjugated polymer (DPP‐BTzTD) together with modified nanoreprecipitation conditions allows to fabricate NIR‐II absorbing Pdots with ultrasmall (4 nm) particle size. Extensive experimental tests demonstrate that the constructed Pdots exhibit good biocompatibility, excellent photostability, bright photoacoustic signals, and high photothermal conversion efficiency (53%). In addition, upon tail‐vein intravenous injection of tumor‐bearing mice, Pdots also show high‐efficient tumor ablation capability with rapid excretion from the body. In particular, both in vitro and in vivo assays indicate that the Pdots possess remarkable PTT performance under irradiation with a 1064 nm laser with 0.5 W cm^?2, which is much lower than its maximum permissible exposure limit of 1 W cm^?2. This pilot study thus paves a novel avenue for the development of organic semiconducting nanoagents for future clinical translation.     

A New Single 808 nm NIR Light‐Induced Imaging‐Guided Multifunctional Cancer Therapy Platform

The NIR light‐induced imaging‐guided cancer therapy is a promising route in the targeting cancer therapy field. However, up to now, the existing single‐modality light‐induced imaging effects are not enough to meet the higher diagnosis requirement. Thus, the multifunctional cancer therapy platform with multimode light‐induced imaging effects is highly desirable. In this work, captopril stabilized‐Au nanoclusters Au₂₅(Capt)₁₈?(Au₂₅) are assembled into the mesoporous silica shell coating outside of Nd³⁺‐sensitized upconversion nanoparticles (UCNPs) for the first time. The newly formed Au₂₅ shell exhibits considerable photothermal effects, bringing about the photothermal imaging and photoacoustic imaging properties, which couple with the upconversion luminescence imaging. More importantly, the three light‐induced imaging effects can be simultaneously achieved by exciting with a single NIR light (808 nm), which is also the triggering factor for the photothermal and photodynamic cancer therapy. Besides, the nanoparticles can also present the magnetic resonance and computer tomography imaging effects due to the Gd³⁺ and Yb³⁺ ions in the UCNPs. Furthermore, due to the photodynamic and the photothermal effects, the nanoparticles possess efficient in vivo tumor growth inhibition under the single irradiation of 808 nm light. The multifunctional cancer therapy platform with multimode imaging effects realizes a true sense of light‐induced imaging‐guided cancer therapy.     

Engineering Versatile Nanoparticles for Near‐Infrared Light‐Tunable Drug Release and Photothermal Degradation of Amyloid β

Nanomedicines that inhibit/disassemble amyloid β (Aβ) aggregates in Alzheimer's disease (AD) are highly desirable yet remain challenging. Therapeutic efficacy and systemic delivery of reported molecules and nanoparticles (NPs) are hampered by various challenges, including low biocompatibility, off‐target toxicity, and lack of specificity. Herein, a versatile NP is designed by integrating high Aβ‐binding affinity, stimuli‐responsive drug release, and photothermal degradation properties for efficient disassembly of Aβ. Near‐infrared (NIR)‐absorbing conjugated polymer PDPP3T‐O14 serves as a photothermal core while thermal‐responsive polymer 1,2‐dipalmitoyl‐sn‐glycero‐3‐phosphocholine at the outer layer as the NIR‐stimuli gatekeeper. Curcumin, an inhibitor of Aβ aggregation, is loaded into the NP with high encapsulation efficiency. The 5‐mer β‐sheet breaker peptides LPFFD (Leu‐Pro‐Phe‐Phe‐Asp) having high binding affinity toward Aβ are further anchored onto the surface of polyethylene glycol‐lipid shell for active Aβ‐targeting. The resultant NPs exhibit good Aβ‐targeting ability and obvious photothermal dissociation effect together with Aβ aggregation‐dependent fluorescence detection capability. Upon NIR laser irradiation, entrapped curcumin can be effectively released from the unconsolidated NPs to enhance the anti‐amyloid activity. In vitro studies demonstrate that the NPs dramatically lower Aβ‐induced cytotoxicity of PC12 cells, and therefore show great potential for the application in AD treatment.     

Selective Photothermal Tumor Therapy Using Nanodiamond‐Based Nanoclusters with Folic Acid

This paper describes the fabrication and evaluation of folic acid (FA)‐conjugated nanodiamond (ND) nanoclusters for selective photothermal tumor therapy. ND nanoclusters with surface carboxyl groups are aminated using ethylenediamine and conjugated with FA via carbodiimide chemistry. The temperature of an aqueous ND dispersion (10 μg mL^?1) is increased to 54 °C upon laser exposure for 5 min. FA‐ND nanoclusters are preferentially taken up by KB cells (folate receptor positive) compared to WI‐38 (folate receptor negative) cells, suggesting specificity for tumor cells that overexpress folate receptors. Cell viability tests reveal that FA‐ND nanoclusters effectively and selectively ablate KB cells upon near‐infrared (NIR) laser exposure. In addition, fluorescence microscopy images confirm that only KB cells treated with FA‐ND nanoclusters are ablated in a spot (200 μm in diameter) by NIR laser exposure. In an animal model, a large amount of FA‐ND nanoclusters is accumulated into tumor tissue, resulting in dramatically reduced tumor volume post‐NIR laser exposure as compared to ND nanoclusters.     

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.     

Theranostic Prodrug Vesicles for Reactive Oxygen Species‐Triggered Ultrafast Drug Release and Local‐Regional Therapy of Metastatic Triple‐Negative Breast Cancer

A reactive oxygen species (ROS)‐activatable doxorubicin (Dox) prodrug vesicle (RADV) is presented for image‐guided ultrafast drug release and local‐regional therapy of the metastatic triple‐negative breast cancer (TNBC). RADV is prepared by integrating a ROS‐activatable Dox prodrug, a poly(ethylene glycol) (PEG)‐modified photosensitizer pyropheophorbide‐a, an unsaturated phospholipid 1,2‐dioleoyl‐sn‐glycero‐3‐phosphocholine, and cholesterol into one single nanoplatform. RADV is of extremely high drug loading ratio (27.5 wt%) by self‐assembly of the phospholipid‐mimic Dox prodrug into the liposomal bilayer membrane. RADV displays good colloidal stability to prevent premature drug leakage during the blood circulation and inert photochemotoxicity to avoid nonspecific side effect. RADV passively accumulates at tumor site through the enhanced permeability and retention effect when administrated systemically. Once deposited at the tumor site, RADV generates fluorescent and photoacoustic signals to guide near‐infrared (NIR) laser irradiation, which can induce localized ROS generation, not only to trigger prodrug activation and ultrafast drug release but also conduct photodynamic therapy in a spatiotemporally controlled manner. In combination with NIR laser irradiation, RADV efficiently inhibits the tumor growth and distant metastasis of TNBC. Local‐regional tumor therapy using intelligent theranostic nanomedicine might provide an alternative option for highly efficient treatment of the metastatic TNBC.     

Ultra‐Small Iron Oxide Doped Polypyrrole Nanoparticles for In Vivo Multimodal Imaging Guided Photothermal Therapy

Recently, near‐infrared (NIR) absorbing conjugated polymeric nanoparticles have received significant attention in photothermal therapy of cancer. Herein, polypyrrole (PPy), a NIR‐absorbing conjugate polymer, is used to coat ultra‐small iron oxide nanoparticles (IONPs), obtaining multifunctional IONP@PPy nanocomposite which is further modified by the biocompatible polyethylene glycol (PEG) through a layer‐by‐layer method to acquire high stability in physiological solutions. Utilizing the optical and magnetic properties of the yielded IONP@PPy‐PEG nanoparticles, in vivo magnetic resonance (MR) and photoacoustic imaging of tumor‐bearing mice are conducted, revealing strong tumor uptake of those nanoparticles after intravenous injection. In vivo photothermal therapy is then designed and carried out, achieving excellent tumor ablation therapeutic effect in mice experiments. These results promise the use of multifunctional NIR‐absorbing organic‐inorganic hybrid nanomaterials, such as IONP@PPy‐PEG presented here, for potential applications in cancer theranostics.     

Enhancing Therapeutic Efficacy of Combined Cancer Phototherapy by Ultrasound‐Mediated In Situ Conversion of Near‐Infrared Cyanine/Porphyrin Microbubbles into Nanoparticles

Nanoparticles (NPs)‐based diagnosis and phototherapy are emerging as the cutting‐edge technologies for detection and treatment of cancer but their applications are still limited since insufficient and heterogeneous NPs accumulation in cancer often causes recurrence. To overcome these limitations, multifunctional microbubbles (MBs) were constructed with 1, 1‐dioctadecyl‐3, 3, 3, 3‐tetramethylindotricarbocyanine iodide (DiR) and porphyrin grafted lipid (PGL). Both DiR and PGL self‐assembled as microbubbles, the as‐designed PGL‐DiR MBs possess remarkably high drug loading contents (5.8% PGL and 10.38% DiR) and stable co‐delivery drug combinations. In vivo experiments showed PGL‐DiR MBs could serve as an excellent ultrasound contrast agent to enhance ultrasound imaging greatly for identifying the location and size of the tumors. Upon exposure to ultrasound, in situ conversion of PGL‐DiR MBs into nanoparticles resulted in a remarkable increase in fluorescence intensity (~5 folds) in tumor compared with PGL‐DiR NPs, validating the enhanced tumor accumulation and cellular uptake of therapeutic agents. PGL‐DiR MBs showed complete tumor ablation without recurrence in vivo, while PGL‐DiR NPs showed only 72.6% tumor growth inhibition at the same dose. We believe that PGL‐DiR MBs will soon reach their full potential as an important class of phototherapeutic formulations and will contribute to remarkable advances in cancer treatments.     

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.     

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.     

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.     

Design and Synthesis of “All‐in‐One” Multifunctional FeS2 Nanoparticles for Magnetic Resonance and Near‐Infrared Imaging Guided Photothermal Therapy of Tumors

The ideal theranostic nanoplatform for tumors is a single nanoparticle that has a single semiconductor or metal component and contains all multimodel imaging and therapy abilities. The design and preparation of such a nanoparticle remains a serious challenge. Here, with FeS₂ as a model of a semiconductor, the tuning of vacancy concentrations for obtaining “all‐in‐one” type FeS₂ nanoparticles is reported. FeS₂ nanoparticles with size of ≈30 nm have decreased photoabsorption intensity from the visible to near‐infrared (NIR) region, due to a low S vacancy concentration. By tuning their shape/size and then enhancing the S vacancy concentration, the photoabsorption intensity of FeS₂ nanoparticles with size of ≈350 nm (FeS₂‐350) goes up with the increase of the wavelength from 550 to 950 nm, conferring the high NIR photothermal effect for thermal imaging. Furthermore, this nanoparticle has excellent magnetic properties for T₂‐weighted magnetic resonance imaging (MRI). Subsequently, FeS₂‐350 phosphate buffer saline (PBS) dispersion is injected into the tumor‐bearing mice. Under the irradiation of 915‐nm laser, the tumor can be ablated and the metastasis lesions in liver suffer significant inhibition. Therefore, FeS₂‐350 has great potential to be used as novel “all‐in‐one” multifunctional theranostic nanoagents for MRI and NIR dual‐modal imaging guided NIR‐photothermal ablation therapy (PAT) of tumors.     

Mitochondria‐Targeted Small‐Molecule Fluorophores for Dual Modal Cancer Phototherapy

Mitochondria are recognized as the ideal target for cancer treatment because they play a central role in oxidative metabolism and apoptosis. In this work, a mitochondria‐targeted near‐infrared (NIR) photosensitizer (PS) for synchronous cancer photodynamic therapy (PDT) and photothermal therapy (PTT) is synthesized. This multifunctional small‐molecule PS is developed from a variety of synthesized heptamethine cyanine dyes, which are modified with various N‐alkyl side chains on the lipophilic cationic heptamethine core. It is demonstrated to preferentially accumulate in cancer cells by organic‐anion transporting polypeptide mediated active transport and retain in mitochondria by its lipophilic cationic property. As mitochondria are susceptible to hyperthermia and excessive reactive oxygen species, this new PS integrating PTT and PDT treatment exhibits highly efficient phototherapy in multiple cancer cells and animal xenograft models. Furthermore, this targeted PS with NIR imaging property also enables tumors and their margins clearly visualized, providing the potential for precisely imaging‐guided phototherapy and treatment monitoring. This is the first report that a small‐molecule PS integrates both cancer PTT and PDT treatment by targeting mitochondria, significantly increasing the photosensitization. This work may also present a practicable strategy to develop small‐molecule‐based cancer theranostic agents for simultaneous cancer targeting, imaging, and therapy.     

Self‐Doped Conjugated Polymeric Nanoassembly by Simplified Process for Optical Cancer Theragnosis

To access smart optical theragnosis for cancer, an easily processable heterocyclic conjugated polymer (poly(sodium3‐((3‐methyl‐3,4‐dihydro‐2H‐thieno[3,4‐b][1,4]dioxepin‐3‐yl)methoxy)propane‐1‐sulfonate), PPDS) nanoassembly is fabricated by a surfactant‐free one‐step process, without the laborious ordinary multicoating process. The conjugated nanoassembly, with a self‐doped structure, provides strong absorbance in the near‐infrared (NIR) range even in a neutral pH medium and exhibits excellent stability (>six months). In addition, the prepared PPDS nanoassembly shows a high photothermal conversion efficiency of 31.4% in organic photothermal nanoparticles. In particular, the PPDS nanoassembly is stably suspended in the biological medium without any additives. Through a simple immobilization with the anti‐CD44 antibody, the prepared biomarker‐targetable PPDS nanoassembly demonstrates specific targeting toward CD44 (expressed in stem‐like cancer cells), allowing NIR absorbance imaging and the efficient targeted photothermal damaging of CD44‐expressing cancer cells, from in vitro 3D mammospheres (similar to the practical structure of tumor in the body) to in vivo xenograft mice tumor models (breast cancer and fibrosarcoma). In this study, the most simplified preparation method is for this organic conjugated polymer‐based nanoassembly by a molecular approach is reported, and demonstrated as a highly promising optical nanoagent for optical cancer theragnosis.     

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.     

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.