Yolk-Shell Nanostructure: An Ideal Architecture to Achieve Harmonious Integration of Magnetic-Plasmonic Hybrid Theranostic Platform

Photothermal therapy and photoacoustic imaging via nanotheranostics in fighting cancer

The nonradiative conversion of light energy into heat (photothermal therapy, PTT) or sound energy (photoacoustic imaging, PAI) has been intensively investigated for the treatment and diagnosis of cancer, respectively. By taking advantage of nanocarriers, both imaging and therapeutic functions together with enhanced tumour accumulation have been thoroughly studied to improve the pre-clinical efficiency of PAI and PTT. In this review, we first summarize the development of inorganic and organic nano photothermal transduction agents (PTAs) and strategies for improving the PTT outcomes, including applying appropriate laser dosage, guiding the treatment via imaging techniques, developing PTAs with absorption in the second NIR window, increasing photothermal conversion efficiency (PCE), and also increasing the accumulation of PTAs in tumours. Second, we introduce the advantages of combining PTT with other therapies in cancer treatment. Third, the emerging applications of PAI in cancer-related research are exemplified. Finally, the perspectives and challenges of PTT and PAI for combating cancer, especially regarding their clinical translation, are discussed. We believe that PTT and PAI having noteworthy features would become promising next-generation non-invasive cancer theranostic techniques and improve our ability to combat cancers.

Fe3O4@ Astragalus Polysaccharide Core-Shell Nanoparticles for Iron Deficiency Anemia Therapy and Magnetic Resonance Imaging in Vivo

Iron deficiency anemia (IDA) is a common nutritional disease suffered by 1 billion people. To develop a new drug which avoids the side effects of traditional oral iron supplementation for IDA treatment, we have designed Fe₃O₄@ Astragalus polysaccharide core-shell nanoparticles (Fe₃O₄@APS NPs) and demonstrated them to be an efficient therapeutic drug for IDA treatment in vivo. The Fe₃O₄@APS NPs have been successfully synthesized with good water solubility and stability, especially in imitated digestion. Cytotoxicity assessment in cells and pathological tests in mice justify their good biocompatibility and low toxicity. The IDA treatment in rats shows that they have efficient therapeutic effect, which is contributed to both the iron element supplement from Fe₃O₄ and the APS-stimulated hematopoietic cell generation. Moreover, the superparamagnetic Fe₃O₄@APS NPs are capable for use as a magnetic resonance imaging contrast agent. This study presents the possibility of nanocomposites involving purified natural products from Chinese herb medicine for biomedical applications.

Energy-Converting Nanomedicine

Serious side effects to surrounding normal tissues and unsatisfactory therapeutic efficacy hamper the further clinic applications of conventional cancer-therapeutic strategies, such as chemotherapy and surgery. The fast development of nanotechnology provides unprecedented superiorities for cancer therapeutics. Externally activatable therapeutic modalities mediated by nanomaterials, relying on highly effective energy transformation to release therapeutic elements/effects (cytotoxic reactive oxygen species, thermal effect, photoelectric effect, Compton effect, cavitation effect, mechanical effect or chemotherapeutic drug) for cancer therapies, categorized and termed as "energy-converting nanomedicine," have arouse considerable concern due to their noninvasiveness, desirable tissue-penetration depth, and accurate modulation of therapeutic dose. This review summarizes the recent advances in the engineering of intelligent functional nanotherapeutics for energy-converting nanomedicine, including photo-based, radiation-based, ultrasound-based, magnetic field-based, microwave-based, electric field-based, and radiofrequency-based nanomedicines, which are enabled by external stimuli (light, radiation, ultrasound, magnetic field, microwave, electric field, and radiofrequency). Furthermore, biosafety issues of energy-converting nanomedicine related to future clinical translation are also addressed. Finally, the potential challenges and prospects of energy-converting nanomedicine for future clinical translation are discussed.

Near-Infrared Light-Triggered Sulfur Dioxide Gas Therapy of Cancer

The exploitation of gas therapy platforms holds great promise as a "green" approach for selective cancer therapy, however, it is often associated with some challenges, such as uncontrolled or insufficient gas generation and unclear therapeutic mechanisms. In this work, a gas therapy approach based on near-infrared (NIR) light-triggered sulfur dioxide (SO₂) generation was developed, and the therapeutic mechanism as well as in vivo antitumor therapeutic efficacy was demonstrated. A SO₂ prodrug-loaded rattle-structured upconversion@silica nanoparticles (RUCSNs) was constructed to enable high loading capacity without obvious leakage and to convert NIR light into ultraviolet light so as to activate the prodrug for SO₂ generation. In addition, SO₂ prodrug-loaded RUCSNs showed high cell uptake, good biocompatibility, intracellular tracking ability, and high NIR light-triggered cytotoxicity. Furthermore, the cytotoxic SO₂ was found to induce cell apoptosis accompanied by the increase of intracellular reactive oxygen species levels and the damage of nuclear DNA. Moreover, efficient inhibition of tumor growth was achieved, associated with significantly prolonged survival of mice. Such NIR light-triggered SO₂ therapy may provide an effective strategy to stimulate further development of synergistic cancer therapy platforms.

Artificial chimeric exosomes for anti-phagocytosis and targeted cancer therapy

Development of exosome-based delivery systems is still facing some formidable challenges, including the lack of standardized isolation and purification methods, non-large-scale production and low drug-loading efficiency. Inspired by biomimetic technologies, we turned to the design of artificial chimeric exosomes (ACEs) constructed by integrating cell membrane proteins from multiple cell types into synthetic phospholipid bilayers. For benchmarking, hybrid membrane proteins derived from red blood cells (RBCs) and MCF-7 cancer cells were selected as models. The resulting ACEs were engineered much like "Emperor Qin's Terra-Cotta Warriors", simultaneously equipped with armor (anti-phagocytosis capability from RBCs) and dagger-axes (homologous targeting ability from cancer cells). ACEs demonstrated higher tumor accumulation, lower interception and better antitumor therapeutic effect than plain liposomes in vivo, alongside large-scale standardized preparation, stable structure, high drug-loading capacity and custom-tailored functionality, highlighting the suitability of ACEs as promising alternatives of exosomes in clinical applications.

X-ray-activated nanosystems for theranostic applications

X-rays are widely applied in clinical medical facilities for radiotherapy (RT) and biomedical imaging. However, the sole use of X-rays for cancer treatment leads to insufficient radiation energy deposition due to the low X-ray attenuation coefficients of living tissues and organs, producing unavoidable excessive radiation doses with serious side effects to healthy body parts. Over the past decade, developments in materials science and nanotechnology have led to rapid progress in the field of X-ray-activated tumor-targeting nanosystems, which are able to tackle even systemic tumors and relieve the burden of exposure to large radiation doses. Additionally, novel imaging contrast agents and techniques have also been developed. In comparison with conventional external light sources (e.g., near infrared), the X-ray technique is ideal for the activation of nanosystems for cancer treatment and biomedical imaging applications due to its nearly unlimited penetration depth in living tissues and organisms. In this review, we systematically describe the interaction mechanisms between X-rays and nanosystems, and provide an overview of X-ray-sensitive materials and the recent progress on X-ray-activated nanosystems for cancer-associated theranostic applications.

Beyond the Roles in Biomimetic Chemistry: An Insight into the Intrinsic Catalytic Activity of an Enzyme for Tumor-Selective Phototheranostics

Protein-assisted biomimetic synthesis has been an emerging offshoot of nanofabrication in recent years owing to its features of green chemistry, facile process, and ease of multi-integration. As a result, many proteins have been used for biomimetic synthesis of varying kinds of nanostructures. Although the efforts on exploring new proteins and investigating their roles in biomimetic chemistry are increasing, the most essential intrinsic properties of proteins are largely neglected. Herein we report a frequently used enzyme (horseradish peroxidase, HRP) to demonstrate the possibility of enzymatic activity retaining after accomplishing the roles in biomimetic synthesis of ultrasmall gadolinium (Gd) nanodots and stowing its substrate 2,2'-Azinobis (3-ethylbenzothiazoline-6-sulfonic acid ammonium salt) (ABTS), denoted as Gd@HRP^ABTS. It was found that ca. 70% of the enzymatic activity of HRP was preserved. The associated changes of protein structure with chemical treatments were studied by spectroscopic analysis. Leveraging on the highly retained catalytic activity, Gd@HRP^ABTS exerts strong catalytic oxidation of peroxidase substrate ABTS into photoactive counterparts in the presence of intrinsic H₂O₂ inside the tumor, therefore enabling tumor-selective catalytic photoacoustic (PA) imaging and photothermal therapy (PTT). In addition, the MR moiety of Gd@HRP^ABTS provides guidance for PTT and further diagrams that Gd@HRP^ABTS is clearable from the body via kidneys. Preliminary toxicity studies show no observed adverse effects by administration of them. This study demonstrates beyond the well-known roles in biomimetic chemistry that HRP can also preserve its enzymatic activity for tumor catalytic theranostics.

Synthesis and Biomedical Applications of Multifunctional Nanoparticles

The accumulated knowledge of nanoparticle (NP) synthesis for the last 30 years has enabled the development of functional NPs for biomedical applications. Especially, NPs with multifunctional capabilities are gaining popularity as the demand for versatile and efficient NP agents increases. Various combinations of functional materials are integrated to form multicomponent NPs with designed size, structure, and multifunctionality. Their use as diagnostic and/or therapeutic tools is demonstrated, suggesting their application potentials in healthcare and medical practice. Here, the recent achievements in the synthesis and biomedical applications of multifunctional NPs are summarized. Starting with a brief overview regarding the advances in NP synthesis and accompanying progress in nanobiotechnology, various components to construct the multifunctional NP agents, which include polymers and mesoporous, magnetic, catalytic, and semiconducting NPs, are discussed together with their overall integration forms, such as NP assembly, hollow/porous structures, or hybrid/doped systems. Following the explanation of the features that multifunctional NP agents can offer, an outlook and a brief comment regarding the future research directions are provided.

Enhancing Antitumor Efficacy by Simultaneous ATP-Responsive Chemodrug Release and Cancer Cell Sensitization Based on a Smart Nanoagent

The exploitation of smart nanoagents based drug delivery systems (DDSs) has proven to be a promising strategy for fighting cancers. Hitherto, such nanoagents still face challenges associated with their complicated synthesis, insufficient drug release in tumors, and low cancer cell chemosensitivity. Here, the engineering of an adenosine triphosphate (ATP)-activatable nanoagent is demonstrated based on self-assembled quantum dots-phenolic nanoclusters to circumvent such challenges. The smart nanoagent constructed through a one-step assembly not only has high drug loading and low cytotoxicity to normal cells, but also enables ATP-activated disassembly and controlled drug delivery in cancer cells. Particularly, the nanoagent can induce cell ATP depletion and increase cell chemosensitivity for significantly enhanced cancer chemotherapy. Systematic in vitro and in vivo studies further reveal the capabilities of the nanoagent for intracellular ATP imaging, high tumor accumulation, and eventual body clearance. As a result, the presented multifunctional smart nanoagent shows enhanced antitumor efficacy by simultaneous ATP-responsive chemodrug release and cancer cell sensitization. These findings offer new insights toward the design of smart nanoagents for improved cancer therapeutics.

Architecture of yolk-shell structured mesoporous silica nanospheres for catalytic applications

We report the design and realization of yolk-shell structured nanospheres with periodic mesoporous organosilica (PMO) nanospheres or noble metal nanoparticles encapsulated in mesoporous silica shells via a selective etching method. These architectures have well controlled structure, size and morphology. The yolk-shell structured PMO@SiO2 nanoparticles can be precisely functionalized with different catalytic functionalities, even incompatible acidic and basic groups: the PMO core with amino (-NH2) groups and the mesoporous silica shell with sulfonic acid (-SO3H) groups. As a nanoreactor, the as-synthesized Au@SiO2 nanospheres show faster reduction of 4-nitrophenol than that of nitrobenzene. Furthermore, the prepared PMO-NH2@SiO2-SO3H nanoparticles can be used as bifunctional catalysts with highly efficient catalytic performance for catalyzing the deacetalization-Henry cascade reaction.

Highly monodisperse beta-cyclodextrin-covellite nanoparticles for efficient photothermal and chemotherapy

High quality covellite phase copper sulfide nanoparticles with excellent photothermal performance were obtained using an easy, non-hot injection method. Then, colloidal stable drug delivery vehicles were fabricated with an amphiphilic polymer and covalently linked with beta-cyclodextrin, which allows the integration of multiple target ligands and drugs, thus providing a versatile nano-platform for efficient photothermal and chemotherapy.

Gadolinium Metallofullerene-Polypyrrole Nanoparticles for Activatable Dual-Modal Imaging-Guided Photothermal Therapy

Accurate diagnosis of tumor is promising to guide photothermal therapy (PTT) for efficacious tumor ablation with minimal damage to healthy tissues. Here, we report an activatable dual-modal imaging agent, which is based on PEGylated-gadolinium metallofullerene-polypyrrole nanoparticle (PEG-GMF-PPy NP) for imaging-guided PTT. A contrast agent (gadolinium metallofullerene, GMF) with excellent magnetic resonance imaging (MRI) performance and an ultra-pH-responsive polymer (PEG-PC7A) are successively modified to the surface of photothermal agent (PPy NP). The prepared PEG-GMF-PPy NPs show strong absorption in the near-infrared (NIR) region, so they can be utilized for photoacoustic imaging. Furthermore, in a tumor extracellular environment, the PEG-GMF-PPy NPs can achieve pH-enhanced MRI because of the hydrophobic-to-hydrophilic conversion of the PC7A. Upon accurate diagnosis-guided NIR laser irradiation, excellent tumor ablation effect is achieved. The results suggest that the PEG-GMF-PPy NPs are promising agents for activatable imaging-guided PTT.

Porous Gold Nanoshells on Functional NH2 -MOFs: Facile Synthesis and Designable Platforms for Cancer Multiple Therapy

AuroShell nanoparticles (sealed gold nanoshell on silica) are the only inorganic materials that are approved for clinical trial for photothermal ablation of solid tumors. Based on that, porous gold nanoshell structures are thus critical for cancer multiple theranostics in the future owing to their inherent cargo-loading ability. Nevertheless, adjusting the diverse experimental parameters of the reported procedures to obtain porous gold nanoshell structures is challenging. Herein, a series of amino-functionalized porous metal-organic frameworks (NH₂ -MOFs) nanoparticles are uncovered as superior templates for porous gold nanoshell deposition (NH₂ -MOFs@Au_shell ) by means of a more facile and general one-step method, which combines the enriched functionalities of NH₂ -MOFs with those of porous gold nanoshells. Moreover, in order to illustrate the promising applications of this method in biomedicine, platinum nanozymes-encapsulated NH₂ -MOFs are further designed with porous gold nanoshell coating and photosensitizer chlorin e6 (Ce6)-loaded nanoparticles with continuous O₂ -evolving ability (Pt@UiO-66-NH₂ @Au_shell -Ce6). The combination of photodynamic and photothermal therapy is then carried out both in vitro and in vivo, achieving excellent synergistic therapeutic outcomes. Therefore, this work not only presents a facile strategy to fabricate functionalized porous gold nanoshell structures, but also illustrates an excellent synergistic tumor therapy strategy.

Near-infrared light triggered drug release from mesoporous silica nanoparticles

Stimuli triggered drug delivery systems enable controlled release of drugs at the optimal space and time, thus achieving optimal therapeutic effects. As one of the most important stimuli used in bioapplications, near-infrared (NIR) light possesses unique advantages such as deep tissue penetration with minimum auto-fluorescence & tissue scattering and high biosafety. Mesoporous silica nanoparticles (MSNs) are one of the most studied nanocarriers; apart from having a high surface area and large pore volume for loading of drugs, they can be easily functionalized with inorganic nanomaterials and stimuli responsive polymers or organic switch molecules, creating possibilities for designing complex stimuli triggered drug delivery systems. Considering the high tissue penetration depth of NIR light and the unique mesoporous structure of MSNs, NIR responsive inorganic nanoparticle functionalized MSNs can be further combined with stimuli responsive materials to form smart "nano-devices" for controlled drug delivery toward tumors, and to date much progress has been made. In this article, recent advances in the design of NIR triggered mesoporous silica drug delivery systems are systematically summarized and some outstanding studies are highlighted. We will also discuss the shortcomings, challenges and opportunities in the field.

Iron Oxide Nanoparticles in Photothermal Therapy

Photothermal therapy is a kind of therapy based on increasing the temperature of tumoral cells above 42 °C. To this aim, cells must be illuminated with a laser, and the energy of the radiation is transformed in heat. Usually, the employed radiation belongs to the near-infrared radiation range. At this range, the absorption and scattering of the radiation by the body is minimal. Thus, tissues are almost transparent. To improve the efficacy and selectivity of the energy-to-heat transduction, a light-absorbing material, the photothermal agent, must be introduced into the tumor. At present, a vast array of compounds are available as photothermal agents. Among the substances used as photothermal agents, gold-based compounds are one of the most employed. However, the undefined toxicity of this metal hinders their clinical investigations in the long run. Magnetic nanoparticles are a good alternative for use as a photothermal agent in the treatment of tumors. Such nanoparticles, especially those formed by iron oxides, can be used in combination with other substances or used themselves as photothermal agents. The combination of magnetic nanoparticles with other photothermal agents adds more capabilities to the therapeutic system: the nanoparticles can be directed magnetically to the site of interest (the tumor) and their distribution in tumors and other organs can be imaged. When used alone, magnetic nanoparticles present, in theory, an important limitation: their molar absorption coefficient in the near infrared region is low. The controlled clustering of the nanoparticles can solve this drawback. In such conditions, the absorption of the indicated radiation is higher and the conversion of energy in heat is more efficient than in individual nanoparticles. On the other hand, it can be designed as a therapeutic system, in which the heat generated by magnetic nanoparticles after irradiation with infrared light can release a drug attached to the nanoparticles in a controlled manner. This form of targeted drug delivery seems to be a promising tool of chemo-phototherapy. Finally, the heating efficiency of iron oxide nanoparticles can be increased if the infrared radiation is combined with an alternating magnetic field.

Simple construction of Cu2-xS:Pt nanoparticles as nanotheranostic agent for imaging-guided chemo-photothermal synergistic therapy of cancer

Synergistic therapy has attracted intense attention in medical treatment because it can make up for the disadvantages of single therapy and greatly improve the efficacy of cancer treatment. However, it remains a challenge to build a simple system to achieve synergistic therapy. In this study, X-ray computed tomography (CT) imaging-guided chemo-photothermal synergistic therapy can be easily achieved by simple construction of Cu2-xS:Pt(0.3)/PVP nanoparticles (NPs). Cu2-xS:Pt(0.3)/PVP NPs can passively accumulate within the tumor sites, thus ensuring that many Cu2-xS:Pt(0.3)/PVP NPs are brought into the tumor cells, which can be confirmed by the results of cellular uptake, imaging, and nanoparticle biodistribution. It can be verified that the platinum ions can be released from Cu2-xS:Pt(0.3)/PVP NPs under 808 nm laser irradiation. Simultaneously, Pt(iv) ions are reduced to Pt(ii) ions by excess glutathione and then, they exhibit chemo-anticancer activities. In addition, Cu2-xS:Pt(0.3)/PVP NPs can be used as an effective photothermal agent. The results demonstrate that the efficient tumor growth inhibition effect can be realized from the mice treated with Cu2-xS:Pt(0.3)/PVP NPs under 808 nm laser irradiation by chemo-photothermal synergistic therapy. Furthermore, Cu2-xS:Pt(0.3)/PVP NPs can be thoroughly cleared through feces in a short time, showing high biosafety for further potential clinical translations.

Yolk-Shell Nanostructures: Design, Synthesis, and Biomedical Applications

Yolk-shell nanostructures (YSNs) composed of a core within a hollow cavity surrounded by a porous outer shell have received tremendous research interest owing to their unique structural features, fascinating physicochemical properties, and widespread potential applications. Here, a comprehensive overview of the design, synthesis, and biomedical applications of YSNs is presented. The synthetic strategies toward YSNs are divided into four categories, including hard-templating, soft-templating, self-templating, and multimethod combination synthesis. For the hard- or soft-templating strategies, different types of rigid or vesicle templates are used for making YSNs. For the self-templating strategy, a number of unconventional synthetic methods without additional templates are introduced. For the multimethod combination strategy, various methods are applied together to produce YSNs that cannot be obtained directly by only a single method. The biomedical applications of YSNs including biosensing, bioimaging, drug/gene delivery, and cancer therapy are discussed in detail. Moreover, the potential superiority of YSNs for these applications is also highlighted. Finally, some perspectives on the future research and development of YSNs are provided.

Black Phosphorus Quantum Dots with Renal Clearance Property for Efficient Photodynamic Therapy

Black phosphorus (BP) nanomaterials have emerged as rapidly rising stars in the field of nanomedicine. In this work, BP quantum dots (BPQDs) are synthesized and their potential as photosensitizers is investigated for the first time. The BPQDs present good stability in physiological medium and no appreciable cytotoxicity. More importantly, the BPQDs can be rapidly eliminated from the body in their intact form via renal clearance due to their ultrasmall hydrodynamic diameter (5.4 nm). Both in vitro and in vivo studies indicate that the BPQDs have excellent photodynamic effect under light irradiation that can effectively generate reactive oxygen species to kill cancer cells. The BPQDs thus can serve as biocompatible and powerful photosensitizers for efficient photodynamic therapy.

Copper Manganese Sulfide Nanoplates: A New Two-Dimensional Theranostic Nanoplatform for MRI/MSOT Dual-Modal Imaging-Guided Photothermal Therapy in the Second Near-Infrared Window

Multifunctional nanoplatforms with integrated diagnostic and therapeutic functions have attracted tremendous attention. Especially, the second near-infrared (NIR-II) light response-based nanoplatforms hold great potential in cancer theranostic applications, which is because the NIR-II window provides larger tissue penetration depth and higher maximum permissible exposure (MPE) than that of the well-studied first near-infrared (NIR-I) window. Herein, we for the first time present a two-dimensional (2D)-nanoplatform based on Cu₂MnS₂ nanoplates (NPs) for magnetic resonance imaging (MRI)/multispectral optoacoustic tomography (MSOT) dual-modal imaging-guided photothermal therapy (PTT) of cancer in the NIR-II window. Methods: Cu₂MnS₂ NPs were synthesized through a facile and environmentally friendly process. A series of experiments, including the characterization of Cu₂MnS₂ NPs, the long-term toxicity of Cu₂MnS₂ NPs in BALB/c nude mice, the applications of Cu₂MnS₂ NPs for in vitro and in vivo MRI/MSOT dual-modal imaging and NIR-II PTT of cancer were carried out. Results: The as-synthesized Cu₂MnS₂ NPs exhibit low cytotoxicity, excellent biocompatibility as well as high photothermal conversion efficiency (~49.38%) and outstanding photostability. Together with their good T₁-shortening effect and strong absorbance in the NIR-I and NIR-II region, the Cu₂MnS₂ NPs display high-contrast imaging performance both in MRI and MSOT (900 nm laser source). Moreover, the subsequent in vitro and in vivo results demonstrate that the Cu₂MnS₂ NPs possess excellent PTT efficacy under 1064 nm laser irradiation with a low power density (0.6 W cm^-2). In addition, the detailed long-term toxicity studies further confirming the safety of Cu₂MnS₂ NPs in vivo. Conclusion: We have developed a new 2D Cu₂MnS₂ NPs as multifunctional theranostic agents for MRI/MSOT dual-modal imaging-guided PTT of cancer in the NIR-II window. Such biocompatible Cu₂MnS₂ NPs might provide a new perspective for exploring new 2D-based nanoplatforms with improved properties for clinical applications in the future.

A pH-Responsive Yolk-Like Nanoplatform for Tumor Targeted Dual-Mode Magnetic Resonance Imaging and Chemotherapy

Incorporation of T₁ and T₂ contrast material in one nanosystem performing their respective MR contrast role and simultaneously serving as an efficient drug delivery system (DDS) has a significant potential application for clinical diagnosis and chemotherapy of cancer. However, inappropriate incorporation always encountered many issues, such as low contact area of T₁ contrast material with water-proton, inappropriate distance between T₂ contrast material and water molecule, and undesirable disturbance of T₂ contrast material for T₁ imaging. Those issues seriously limited the T₁ or T₂ contrast effect. In this work, we developed a yolk-like Fe₃O₄@Gd₂O₃ nanoplatform functionalized by polyethylene glycol and folic acid (FA), which could efficiently exert their tumor targeted T₁-T₂ dual-mode MR imaging and drug delivery role. First, this nanoplatform possessed a high longitudinal relaxation rate (r₁) (7.91 mM^-1 s^-1) and a stronger transverse relaxation rate (r₂) (386.5 mM^-1 s^-1) than that of original Fe₃O₄ (268.1 mM^-1 s^-1). Second, cisplatin could be efficiently loaded into this nanoplatform (112 mg/g) and showed pH-responsive release behavior. Third, this nanoplatform could be effectively internalized by HeLa cells with time and dosage dependence. Fourth, the FA receptor-mediated nanoplatform displayed excellent T₁-T₂ dual mode MR contrast enhancement and anticancer activity both in vitro and in vivo. Fifth, no apparent toxicity for vital organs was observed with systemic delivery of the nanoplatform in vivo. Thus, this nanoplatform could be a potential nanotheranostic for tumor targeted T₁-T₂ dual-mode MR imaging and chemotherapy.

Nanoparticles as Theranostic Vehicles in Experimental and Clinical Applications-Focus on Prostate and Breast Cancer

Prostate and breast cancer are the second most and most commonly diagnosed cancer in men and women worldwide, respectively. The American Cancer Society estimates that during 2016 in the USA around 430,000 individuals were diagnosed with one of these two types of cancers, and approximately 15% of them will die from the disease. In Europe, the rate of incidences and deaths are similar to those in the USA. Several different more or less successful diagnostic and therapeutic approaches have been developed and evaluated in order to tackle this issue and thereby decrease the death rates. By using nanoparticles as vehicles carrying both diagnostic and therapeutic molecular entities, individualized targeted theranostic nanomedicine has emerged as a promising option to increase the sensitivity and the specificity during diagnosis, as well as the likelihood of survival or prolonged survival after therapy. This article presents and discusses important and promising different kinds of nanoparticles, as well as imaging and therapy options, suitable for theranostic applications. The presentation of different nanoparticles and theranostic applications is quite general, but there is a special focus on prostate cancer. Some references and aspects regarding breast cancer are however also presented and discussed. Finally, the prostate cancer case is presented in more detail regarding diagnosis, staging, recurrence, metastases, and treatment options available today, followed by possible ways to move forward applying theranostics for both prostate and breast cancer based on promising experiments performed until today.

Recent advances in the rational design of copper chalcogenide to enhance the photothermal conversion efficiency for the photothermal ablation of cancer cells

Three rational designs and the mechanism for copper chalcogenide to enhance the heat conversion efficiency were discussed.