One-pot synthesis of PEGylated plasmonic MoO(3-x) hollow nanospheres for photoacoustic imaging guided chemo-photothermal combinational therapy of cancer

Rapid room-temperature preparation of MoO3−x quantum dots by ultraviolet irradiation for photothermal treatment and glucose detection

Oxygen deficient molybdenum oxide (MoO_3−x) spurred intense scientific interest in biomedical research owing to the strong localized surface plasmon resonance (LSPR) effect in NIR region.

All-in-One Theranostic Nanoplatform Based on Hollow MoSx for Photothermally-maneuvered Oxygen Self-enriched Photodynamic Therapy

Photodynamic therapy (PDT) kills cancer cells by converting tumor-dissolved oxygen into reactive singlet oxygen (¹O₂) using a photosensitizer under laser irradiation. However, pre-existing hypoxia in tumors and oxygen consumption during PDT can result in an inadequate oxygen supply, which in turn hampers PDT efficacy. Herein, an O₂ self-sufficient nanotheranostic platform based on hollow MoS_x nanoparticles (HMoS_x) with oxygen-saturated perfluorohexane (O₂@PFH) and surface-modified human serum albumin (HSA)/chloride aluminium phthalocyanine (AlPc) (O₂@PFH@HMoS_x-HSA/AlPc), has been designed for the imaging and oxygen self-enriched photodynamic therapy (Oxy-PDT) of cancer.

Methods: The in vitro anti-cancer activity and intracellular ¹O₂ generation performance of the nanoparticles were examined using 4T1 cells. We also evaluated the multimodal imaging capabilities and anti-tumor efficiency of the prepared nanoparticles in vivo using a 4T1 tumor-bearing nude mouse model.

Results: This nanoplatform could achieve the distinct in vivo fluorescence (FL)/photoacoustic (PA)/X-ray computed tomography (CT) triple-model imaging-guided photothermally-maneuvered Oxy-PDT. Interestingly, the fluorescence and Oxy-PDT properties of O₂@PFH@HMoS_x-HSA/AlPc were considerably quenched; however, photothermal activation by 670 nm laser irradiation induced a significant increase in temperature, which empowered the Oxy-PDT effect of the nanoparticles. In this study, O₂@PFH@HMoS_x-HSA/AlPc demonstrated a great potential to image and treat tumors both in vitro and in vivo, showing complete tumor-inhibition over 16 days after treatment in the 4T1 tumor model.

Conclusion: O₂@PFH@HMoS_x-HSA/AlPc is promising to be used as novel multifunctional theranostic nanoagent for triple-modal imaging as well as single wavelength NIR laser triggered PTT/Oxy-PDT synergistic therapy.

Hydrophilic K2Mn4O8 nanoflowers as a sensitive photothermal theragnosis synergistic platform for the ablation of cancer

Hydrophilic flower-like K₂Mn₄O₈ is fabricated and works simultaneously as an effective photothermal agent and an ultrasensitive T₁-weighted MRI enhancing agent.

Plasmonic CuS nanodisk assembly based composite nanocapsules for NIR-laser-driven synergistic chemo-photothermal cancer therapy

The NIR-laser-driven plasmonic photothermal and sustained drug release behavior of CuS–PTX/SiO₂ nanocapsules show great synergistic chemo-photothermal therapeutic effects on cancer cells in vitro and in vivo.

In Vivo Imaging-Guided Photothermal/Photoacoustic Synergistic Therapy with Bioorthogonal Metabolic Glycoengineering-Activated Tumor Targeting Nanoparticles

Developing multifunctional phototheranostics with nanoplatforms offers promising potential for effective eradication of malignant solid tumors. In this study, we develop a multifunctional phototheranostic by combining photothermal therapy (PTT) and photoacoustic therapy (PAT) based on a tumor-targeting nanoagent (DBCO-ZnPc-LP). The nanoagent DBCO-ZnPc-LP was facilely prepared by self-assembling of a single lipophilic near-infrared (NIR) dye zinc(II)-phthalocyanine (ZnPc) with a lipid-poly(ethylene glycol) (LP) and following modified further with dibenzyl cyclootyne (DBCO) for introducing the two-step chemical tumor-targeting strategy based on metabolic glycoengineering and click chemistry. The as-prepared DBCO-ZnPc-LP could not only convert NIR light into heat for effective thermal ablation but also induce a thermal-enhanced ultrasound shockwave boost to trigger substantially localized mechanical damage, achieving synergistic antitumor effect both in vitro and in vivo. Moreover, DBCO-ZnPc-LP can be efficiently delivered into tumor cells and solid tumors after being injected intravenously via the two-step tumor-targeting strategy. By integrating the targeting strategy, photoacoustic imaging, and the synergistic interaction between PTT and PAT, a solid tumor could be accurately positioned and thoroughly eradicated in vivo. Therefore, this multifunctional phototheranostic is believed to play an important role in future oncotherapy by the enhanced synergistic effect of PTT and PAT under the guidance of photoacoustic imaging.

ZnO-DOX@ZIF-8 Core-Shell Nanoparticles for pH-Responsive Drug Delivery

Developing multifunctional hybrid nanosystems for controlled drug delivery is a challenging task. In this work, we prepared hierarchical core-shell nanoparticles (ZnO-DOX@ZIF-8) composed of mesoporous ZnO core and microporous ZIF-8 shell, in which the core serves as the drug storage reservoir for the loading of anticancer drug doxorubicin (DOX) and the shell could be used to prevent premature release of loaded drug at physiological environment. The mesoporous ZnO nanoparticles were first prepared, followed by DOX drug loading. Such ZnO nanoparticles were then employed as the zinc source to react with 2-methylimidazole for the formation of ZnO-DOX@ZIF-8 core-shell nanoparticles. The core-shell nanoparticles exhibit good dispersibility and stability as well as pH-responsive drug release property. While only up to 20% of loaded DOX was released in the buffer of pH 7.4, over 80% of DOX was released in the buffer of pH 5.5 because of the decomposition of the ZIF-8 shell as well as the dissolution of the ZnO core under acidic conditions. The confocal microscopy studies show that the core-shell nanoparticles could be efficiently internalized by cancer cells, and the loaded DOX in the nanoparticles could be successfully released under acidic intracellular environment. The in vitro cytotoxicity measurements demonstrate that the core-shell nanoparticles free of drug exhibit a significant cytotoxicity when the concentration was above 25 μg/mL on account of the production of reactive oxygen species. The reactive oxygen species are only generated in acidic condition, which could combine with DOX for a synergistic cancer treatment with satisfactory therapeutic efficacy. On the other hand, the nanoparticles were stable and nontoxic in physiological environment. Thus, the ZnO-DOX@ZIF-8 core-shell nanoparticles are a promising pH-responsive drug delivery system for the cancer therapy.

Black TiO2 based core-shell nanocomposites as doxorubicin carriers for thermal imaging guided synergistic therapy of breast cancer

TiO₂ nanomaterials have been widely used for anticancer drug carriers and UV/980 nm NIR triggered cancer synergistic platforms. However, traditional pure TiO₂ nanocarriers encounter some serious drawbacks, such as low drug loading ability, limited tissue penetration of UV light, and heating effect of 980 nm NIR on normal tissue, which obstruct their further application in cancer treatment. To overcome those challenges, novel mesoporous silica (mSiO₂) coated black TiO₂ core-shell nanocomposites are designed and constructed as doxorubicin carriers for 808 nm NIR triggered thermal imaging guided photothermal therapy combined chemotherapy of breast cancer. Properties of the nanocomposites such as micro-morphology, size, drug loading ability and release, targeting performance, and therapy efficiency in vitro and in vivo were evaluated. The results indicated the core-shell nanocomposites with dramatically increased loading ability were pH-responsive/NIR-accelerated doxorubicin release nanocarriers and showed synergistic breast cancer treatment in vitro and in vivo. This study verifies that the newly prepared mSiO₂ coated black TiO₂ core-shell nanocarriers can overcome the limitations of traditional TiO₂ nanocarriers and thus improve and broaden usage of TiO₂ nanoparticles in nanomedicine.

Degradable Hollow Mesoporous Silicon/Carbon Nanoparticles for Photoacoustic Imaging-Guided Highly Effective Chemo-Thermal Tumor Therapy in Vitro and in Vivo

The development of nanoscaled theranostic agents for cancer combination therapies has received intensive attention in recent years. In this report, a degradable hollow mesoporous PEG-Si/C-DOX NP is designed and fabricated for pH-responsive, photoacoustic imaging-guided highly effective chemo-thermal combination therapy. The intrinsic hollow mesoporous structure endows the as-synthesized nanoparticles (NPs) with a high drug loading capacity (31.1%). Under NIR (808 nm) irradiation, the photothermal conversion efficiency of the Si/C NPs is as high as 40.7%. Preferential accumulation of the PEG-Si/C-DOX NPs around tumor tissue was demonstrated with photoacoustic images. Cellular internalization of the NPs and release of the DOX in nuclei are shown with fluorescent images. With efficient NIR photothermal conversion and high DOX loading capacity, the PEG-Si/C-DOX NPs are demonstrated to have remarkable cancer-cell-killing ability and to achieve complete in vivo tumor elimination via combinational chemo-thermal therapy. Last but not least, the NPs show good biodegradability and biosafety, making them a promising candidate for multifunctional drug delivery and cancer theranostic.

Photoacoustic Drug Delivery

Photoacoustic (PA) technology holds great potential in clinical translation as a new non-invasive bioimaging modality. In contrast to conventional optical imaging, PA imaging (PAI) enables higher resolution imaging with deeper imaging depth. Besides applications for diagnosis, PA has also been extended to theranostic applications. The guidance of PAI facilitates remotely controlled drug delivery. This review focuses on the recent development of PAI-mediated drug delivery systems. We provide an overview of the design of different PAI agents for drug delivery. The challenges and further opportunities regarding PA therapy are also discussed.

Strategies to Improve Cancer Photothermal Therapy Mediated by Nanomaterials

The deployment of hyperthermia-based treatments for cancer therapy has captured the attention of different researchers worldwide. In particular, the application of light-responsive nanomaterials to mediate hyperthermia has revealed promising results in several pre-clinical assays. Unlike conventional therapies, these nanostructures can display a preferential tumor accumulation and thus mediate, upon irradiation with near-infrared light, a selective hyperthermic effect with temporal resolution. Different types of nanomaterials such as those based on gold, carbon, copper, molybdenum, tungsten, iron, palladium and conjugated polymers have been used for this photothermal modality. This progress report summarizes the different strategies that have been applied so far for increasing the efficacy of the photothermal therapeutic effect mediated by nanomaterials, namely those that improve the accumulation of nanomaterials in tumors (e.g. by changing the corona composition or through the functionalization with targeting ligands), increase nanomaterials' intrinsic capacity to generate photoinduced heat (e.g. by synthesizing new nanomaterials or assembling nanostructures) or by optimizing the parameters related to the laser light used in the irradiation process (e.g. by modulating the radiation wavelength). Overall, the development of new strategies or the optimization and combination of the existing ones will surely give a major contribution for the application of nanomaterials in cancer PTT.

Multifunctional Theranostic Agent of Cu2(OH)PO4 Quantum Dots for Photoacoustic Image-Guided Photothermal/Photodynamic Combination Cancer Therapy

Image-guided phototherapy is considered to be a prospective technique for cancer treatment because it can provide both oncotherapy and bioimaging, thus achieving an optimized therapeutic efficacy and higher treatment accuracy. Compared to complicated systems with multiple components, using a single material for this multifunctional purpose is preferable. In this work, we strategically fabricated poly(acrylic acid)- (PAA-) coated Cu₂(OH)PO₄ quantum dots [denoted as Cu₂(OH)PO₄@PAA QDs], which exhibit a strong near-infrared photoabsorption ability. As a result, an excellent photothermal conversion ability and the photoactivated formation of reactive oxygen species could be realized upon NIR irradiation, concurrently meeting the basic requirements for photothermal and photodynamic therapies. Moreover, phototherapeutic investigations on both cervical cancer cells in vitro and solid tumors of an in vivo mice model illustrated the effective antitumor effects of Cu₂(OH)PO₄@PAA upon 1064-nm laser irradiation, with no detectable lesions in major organs during treatment. Meanwhile, Cu₂(OH)PO₄@PAA is also an exogenous contrast for photoacoustic tomography (PAT) imaging to depict tumors under NIR irradiation. In brief, the Cu₂(OH)PO₄@PAA QDs prepared in this work are expected to serve as a multifunctional theranostic platform.

Enzyme and Redox Dual-Triggered Intracellular Release from Actively Targeted Polymeric Micelles

Highly effective delivery of therapeutic agents into target cells using nanocarriers and subsequently rapid intracellular release are of great importance in cancer treatment. Here, we developed an enzyme and redox dual-responsive polymeric micelle with active targeting abilities to achieve rapid intracellular drug release. To overcome both its poor solubility in water and instability in the blood circulation, camptothecin (CPT) was chemically conjugated to monomethyl poly(ethylene glycol) (mPEG) via a redox-responsive linker to form polymeric prodrugs. The enzyme-responsive function is achieved by connecting hydrophobic polycaprolactone segments and hydrophilic PEG segments with azo bonds. Additionally, the end of the PEG segment was decorated with phenylboronic acid (PBA), endowing the nanocarriers with active targeting abilities. The dual-responsive targeting polymeric micelles can be generated by self-assembly of a mixture of the polymeric prodrug and enzyme-responsive copolymer. The in vitro drug release profile revealed that CPT was rapidly released from the micelles under a simulated condition similar to the tumor cell microenvironment. In vivo and ex vivo fluorescence imaging indicated that these micelles possess excellent specificity to target hepatoma carcinoma cells. The antitumor effect in mice liver cancer cells (H22) in tumor-bearing Kunming (KM) mice demonstrated that this nanocarrier exhibits high therapeutic efficiency in artificial solid tumors and low toxicity to normal tissues, with a survival rate of approximately 100% after 160 days of treatment.

Stepwise growth of gold coated cancer targeting carbon nanotubes for the precise delivery of doxorubicin combined with photothermal therapy

Combining doxorubicin with thermal therapy in the clinic has led to startling results in the treatment of problematic cancers. Here, we describe a multimodal multi-walled carbon nanotube material that combines tumor targeting, doxorubicin delivery, and photothermal therapy for localized cancer treatment. The agent was constructed layer-by-layer from polypyrrole and gold nanoparticles on multi-walled carbon nanotubes. The gold surface was modified with tumor targeting folic acid terminated PEGylated chains, which also provide water-dispersibility, biocompatibility and should extend the half-life in blood. The material has a high loading/unloading capacity for the cytotoxic agent doxorubicin. Release of the doxorubicin, combined with the photothermal properties of the material that induces localized hyperthermia, leads to efficient cancer cell death.

Functional hollow nanostructures for imaging and phototherapy of tumors

Various types of inorganic and organic phototherapeutic hollow nanostructures for the imaging and treatment of tumors are reviewed.

Two-dimensional transition metal dichalcogenide nanomaterials for combination cancer therapy

In this review, we mainly summarize the latest advances in the utilization of 2D TMDCs for PTT combination cancer therapy and imaging-guided cancer combination therapy, as well as their toxicity bothin vitroandin vivo.

Near-infrared conjugated polymers for photoacoustic imaging-guided photothermal/chemo combination therapy

Conjugated polymers with intensive near-infrared absorption and high photothermal conversion efficiency have emerged as a new generation of photothermal therapy and photoacoustic imaging agents for cancer therapy.

Targeted polydopamine nanoparticles enable photoacoustic imaging guided chemo-photothermal synergistic therapy of tumor

Near infrared light responsive nanoparticles can transfer the absorbed NIR optical energy into heat, offering a desirable platform for photoacoustic (PA) imaging guided photothermal therapy (PTT) of tumor. However, a key issue in exploiting this platform is to achieve optimal combination of PA imaging and PTT therapy in single nanoparticle. Here, we demonstrate that the biodegradable polydopamine nanoparticles (PDAs) are excellent PA imaging agent and highly efficient for PTT therapy, thus enabling the optimal combination of PA imaging and PTT therapy in single nanoparticle. Upon modification with arginine-glycine-aspartic-cysteine acid (RGDC) peptide, PDA-RGDC can successfully target tumor site. Moreover, PDA-RGDC can load a chemotherapy drug, doxorubicin (DOX), whose release can be triggered by near-infrared (NIR) light and pH dual-stimuli. The in vitro and in vivo experiments show that this platform can deliver anti-cancer drugs to target cells, release them intracellular upon NIR irradiation, and effectively eliminate tumors through chemo-photothermal synergistic therapeutic effect. Our results offer a way to harness PDA-based theranostic agents to achieve PA imaging-guided cancer therapy.

STATEMENT OF SIGNIFICANCE

NIR-light adsorbed nanoparticles combing the advantage of PAI and PTT (TNP-PAI/PTT) are expected to play a significant role in the dawning era of personalized medicine. However, the reported Au-, Ag-, Cu-, Co-, and other metal based, carbon-based TNP-PAI/PTT suffer from complex multicomponent system and poor biocompatibility and biodegradability. To overcome this limitation, biocompatible polydopamine nanoparticles (PDAs), structurally similar to naturally occurring melanin, were designed as both PA imaging contrast agent and a chemo-thermotherapy therapy agent for tumor. RGDC peptide modified PDAs can improve the PA imaging and PTT efficiency and specific targeted deliver doxorubicin (DOX) to perinuclear region of tumor cells. Our finding may help the development of PDA-based nanoplatform for PA imaging-directed synergistic therapy of tumor in clinic.

A Multifunctional Platform for Tumor Angiogenesis-Targeted Chemo-Thermal Therapy Using Polydopamine-Coated Gold Nanorods

Image-guided combined chemo-thermal therapy assists in optimizing treatment time, enhancing therapeutic efficiency, and circumventing side effects. In the present study, we developed a chemo-photothermal theranostic platform based on polydopamine (PDA)-coated gold nanorods (GNRs). The PDA coating was thin; however, it significantly suppressed the cytotoxicity of the cetyltrimethylammonium bromide template and allowed high cisplatin loading efficiency, arginine-glycine-aspartic acid (RGD) peptide (c(RGDyC)) conjugation, and chelator-free iodine-125 labeling (RGD-¹²⁵IPt-PDA@GNRs). While loaded cisplatin was released in a pH-sensitive manner, labeled ¹²⁵I was outstandingly stable under biological conditions. RGD-¹²⁵IPt-PDA@GNRs had a high specificity for αvβ₃ integrin, and consequently, they could selectively accumulate in tumors, as revealed by single photon emission computed tomography/CT imaging, and in target tumor angiogenic vessels, as shown by high-resolution photoacoustic imaging. As RGD-¹²⁵IPt-PDA@GNRs targets tumor angiogenesis, it is a highly potent tumor therapy. Combined chemo-photothermal therapy with probes could thoroughly ablate tumors and inhibit tumor relapse via a synergistic antitumor effect. Our studies demonstrated that RGD-¹²⁵IPt-PDA@GNRs is a robust platform for image-guided, chemo-thermal tumor therapy with outstanding synergistic tumor killing and relapse inhibition effects.

Functional computer-to-plate near-infrared absorbers as highly efficient photoacoustic dyes

Photoacoustic imaging (PAI) is an emerging modality in biomedical imaging. Photoacoustic effect is the basis for PAI, where a photoacoustic contrast agent absorbs optical pulses to initiate localized heating and rapid thermal expansion, thus generating thermoelastic stress waves. Therefore, ideal PAI dyes should have strong NIR light absorbance and high light-heat conversion efficiency. However, most current low molecular weight organic PAI contrast agents are fluorescent dyes, where the light-heat conversion efficiency is dramatically impaired due to the energy loss by fluorescence emission. Herein, we report a series of highly efficient photoacoustic dyes with COOH, NH2 and NHS ester functionalities, from an inexpensive industrial computer-to-plate NIR absorber (IR830 p-toluenesulfonate) that has a strong NIR absorbance but an extremely low fluorescence emission. In vitro and in vivo studies show that the functional IR830 dyes have low cytotoxicity, and are 2.1 folds brighter in photoacoustic imaging than traditional photoacoustic dye indocyanine green (ICG). The Lowest Limit of Quantification of the IR830 series dyes is as low as the 1/7 of that of ICG. These indicate that the functional IR830 dyes have great potential as highly efficient photoacoustic dyes.

STATEMENT OF SIGNIFICANCE

Photoacoustic imaging (PAI) is an emerging modality in biomedical imaging. Ideal PAI dyes should have strong NIR absorbance and high light-heat conversion efficiency. However, most current low molecular weight organic PAI contrast agents are fluorescent dyes, where the light-heat conversion efficiency is dramatically impaired due to the energy loss by fluorescence emission. Herein we report a series of highly efficient functional photoacoustic dyes from an inexpensive industrial computer-to-plate NIR absorber (IR830) that has a strong NIR absorbance but an extremely low fluorescence emission. The functional IR830 dyes show low cytotoxicity, much brighter in photoacoustic imaging than traditional photoacoustic dye indocyanine green. These indicate that the functional IR830 dyes have great potential as highly efficient photoacoustic dyes.

Cellulose acetate-based composites with antimicrobial properties from embedded molybdenum trioxide particles

The objective of this research was to develop novel cellulose acetate (biopolymer) composite materials with an excellent antimicrobial activity by embedding molybdenum trioxide particles with unique high specific surface area. High surface area molybdenum trioxide particles were prepared from freshly precipitated molybdenum trioxide dihydrate (MoO₃ ·2H₂ O) and subsequent calcination at 340°C under H₂ /N₂ gas. Microbiological evaluation against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa were performed applying a roll-on test and excellent antimicrobial activities were determined for composites with embedded anhydrous molybdenum trioxide with a high specific surface area. Cellulose acetate composites comprising MoO₃ particles can eliminate three harmful bacteria as a result of the release of protons from the material and surface enlargement of the molybdenum trioxide particles. The findings support a proposed antimicrobial mechanism based on local acidity increase due to large specific surface areas.

SIGNIFICANCE AND IMPACT OF THE STUDY

In this study, development of a novel thermoplastic bio-based composite with excellent antimicrobial surface properties is investigated. To the best of our knowledge, this is the first report to evaluate the antimicrobial properties of molybdenum trioxide embedded into a cellulose acetate as biopolymer matrix. The developed composites might step up to innovative applications used in modern medical and public environments.

Recent advances in different modal imaging-guided photothermal therapy

Photothermal therapy (PTT) has recently attracted considerable attention owing to its controllable treatment process, high tumour eradication efficiency and minimal side effects on non-cancer cells. PTT can melt cancerous cells by localising tissue hyperthermia induced by internalised therapeutic agents with a high photothermal conversion efficiency under external laser irradiation. Numerous in vitro and in vivo studies have shown the significant potential of PTT to treat tumours in future practical applications. Unfortunately, the lack of visualisation towards agent delivery and internalisation, as well as imaging-guided comprehensive evaluation of therapeutic outcome, limits its further application. Developments in combined photothermal therapeutic nanoplatforms guided by different imaging modalities have compensated for the major drawback of PTT alone, proving PTT to be a promising technique in biomedical applications. In this review, we introduce recent developments in different imaging modalities including single-modal, dual-modal, triple-modal and even multi-modal imaging-guided PTT, together with imaging-guided multi-functional theranostic nanoplatforms.

Polypyrrole-encapsulated iron tungstate nanocomposites: a versatile platform for multimodal tumor imaging and photothermal therapy

A versatile nanoplatform of FeWO4@Polypyrrole (PPy) core/shell nanocomposites, which was facilely fabricated by first hydrothermal synthesis of FeWO4 nanoparticles and subsequent surface-coating of polypyrrole shell, was developed as an effective nanotheranostic agent of cancer. The as-prepared nanocomposites demonstrated excellent dispersion in saline, long-term colloidal storage, outstanding photo-stability and high photothermal efficiency in solution. In particular, FeWO4@PPy exhibited efficient performance for hyperthermia-killing of cancer cells under the irradiation of an 808 nm laser, accompanied with multimodal contrast capabilities for magnetic resonance imaging, X-ray computed tomography and infrared thermal imaging in vitro and in vivo. Furthermore, the nanocomposites presented impactful tumor growth inhibition and good biocompability in animal experiments. Blood circulation and biodistribution of the nanocomposites were also investigated to understand their in vivo behaviours. Our results verified the platform of FeWO4@PPy nanocomposites as a promising photothermal agent for imaging-guided cancer theranostics.

Mesoporous Bamboo Charcoal Nanoparticles as a New Near-Infrared Responsive Drug Carrier for Imaging-Guided Chemotherapy/Photothermal Synergistic Therapy of Tumor

Near-infrared-(NIR)-light-triggered photothermal nanocarriers have attracted much attention for the construction of more smart and effective therapeutic platforms in nanomedicine. Here, a multifunctional drug carrier based on a low cost, natural, and biocompatible material, bamboo charcoal nanoparticles (BCNPs), which are prepared by the pyrolysis of bamboo followed by physical grinding and ultrasonication is reported. The as-prepared BCNPs with porous structure possess not only large surface areas for drug loading but also an efficient photothermal effect, making them become both a suitable drug carrier and photothermal agent for cancer therapy. After loading doxorubicin (DOX) into the BCNPs, the resulting DOX-BCNPs enhance drug potency and more importantly can overcome the drug resistance of DOX in a MCF-7 cancer cell model by significantly increasing cellular uptake while remarkably decreasing drug efflux. The in vivo synergistic effect of combining chemotherapy and photothermal therapy in this drug delivery system is also demonstrated. In addition, the BCNPs enhance optoacoustic imaging contrast due to their high NIR absorbance. Collectively, it is demonstrated that the BCNP drug delivery system constitutes a promising and effective nanocarrier for simultaneous bioimaging and chemo-photothermal synergistic therapy of cancer.

Dual-Modal Imaging-Guided Theranostic Nanocarriers Based on Indocyanine Green and mTOR Inhibitor Rapamycin

The development of treatment protocols that resulted in a complete response to photothermal therapy (PTT) was usually hampered by uneven heat distribution and low effectiveness. Here, we reported an NIR fluorescence and photoacoustic dual-modal imaging-guided active targeted thermal sensitive liposomes (TSLs) based on the photothermal therapy agent Indocyanine green (ICG) and antiangiogenesis agent Rapamycin (RAPA) to realize enhanced therapeutic and diagnostic functions. As expected, the in vitro drug release studies exhibited the satisfactory result of drug released from the TSLs under hyperthermia conditions induced by NIR stimulation. The in vitro cellular studies confirmed that the FA-ICG/RAPA-TSLs plus NIR laser exhibited efficient drug accumulation and cytotoxicity in tumor cells and epithelial cells. After 24 h intravenous injection of FA-ICG/RAPA-TSLs, the margins of tumor and normal tissue were accurately identified via the in vivo NIR fluorescence and photoacoustic dual-modal imaging. In addition, FA-ICG/RAPA-TSLs combined with NIR irradiation treated tumor-bearing nude mice inhibited tumor growth to a great extent and possessed much lower side effects to normal organs. All detailed evidence suggested that the theranostic TSLs which were capable of enhancing the therapeutic index might be a suitable drug delivery system for dual-modal imaging-guided therapeutic tools for diagnostics as well as the treatment of tumors.

Multifunctional Inorganic Nanoparticles: Recent Progress in Thermal Therapy and Imaging

Nanotechnology has enabled the development of many alternative anti-cancer approaches, such as thermal therapies, which cause minimal damage to healthy cells. Current challenges in cancer treatment are the identification of the diseased area and its efficient treatment without generating many side effects. Image-guided therapies can be a useful tool to diagnose and treat the diseased tissue and they offer therapy and imaging using a single nanostructure. The present review mainly focuses on recent advances in the field of thermal therapy and imaging integrated with multifunctional inorganic nanoparticles. The main heating sources for heat-induced therapies are the surface plasmon resonance (SPR) in the near infrared region and alternating magnetic fields (AMFs). The different families of inorganic nanoparticles employed for SPR- and AMF-based thermal therapies and imaging are described. Furthermore, inorganic nanomaterials developed for multimodal therapies with different and multi-imaging modalities are presented in detail. Finally, relevant clinical perspectives and the future scope of inorganic nanoparticles in image-guided therapies are discussed.

Doxorubicin-loaded ionic liquid–polydopamine nanoparticles for combined chemotherapy and microwave thermal therapy of cancer

Doxorubicin-loaded ionic liquid–polydopamine (IL–PDA–DOX) nanocomposites were obtained with high antitumor efficacy for combined chemotherapy and microwave thermal therapy of cancer.