FePt@CoS(2) yolk-shell nanocrystals as a potent agent to kill HeLa cells

Fabrication of Yolk-Shell Structure with Multifarious Nanoparticles via Double-Layered Encapsulation Strategy

The post-encapsulation method (such as single-layered encapsulation) is a promising strategy to synthesize yolk-shell structures that protect functional nanoparticles by the molecular sieving effect. However, this method exhibited limited loading capacity and nonuniform encapsulation during the co-encapsulation of various nanoparticles owing to the insufficient surface area for nanoparticle attachment. To address these limitations, we proposed a double-layered encapsulation method comprising an increased number of silica template layers and separate attachment of multifarious nanoparticles to different layers. Compared with conventional methods, this strategy can precisely adjust the ratio of encapsulated nanoparticles and increase the loading amount, which improves the functionality of yolk-shell structures, such as the photothermal properties of gold nanoparticle-encapsulated yolk-shell structures (∼69%). We describe, for the first time, the precise control of the ratio of encapsulated nanoparticles and the loading of numerous nanoparticles. Consequently, this strategy has significant potential for various applications of yolk-shell structures.

Partial Chemicalization of Nanoscale Metals: An Intra-Material Transformative Approach for the Synthesis of Functional Colloidal Metal-Semiconductor Nanoheterostructures

Heterostructuring colloidal nanocrystals into multicomponent modular constructs, where domains of distinct metal and semiconductor phases are interconnected through bonding interfaces, is a consolidated approach to advanced breeds of solution-processable hybrid nanomaterials capable of expressing richly tunable and even entirely novel physical-chemical properties and functionalities. To meet the challenges posed by the wet-chemical synthesis of metal-semiconductor nanoheterostructures and to overcome some intrinsic limitations of available protocols, innovative transformative routes, based on the paradigm of partial chemicalization, have recently been devised within the framework of the standard seeded-growth scheme. These techniques involve regiospecific replacement reactions on preformed nanocrystal substrates, thus holding great synthetic potential for programmable configurational diversification. This review article illustrates achievements so far made in the elaboration of metal-semiconductor nanoheterostructures with tailored arrangements of their component modules by means of conversion pathways that leverage on spatially controlled partial chemicalization of mono- and bi-metallic seeds. The advantages and limitations of these approaches are discussed within the context of the most plausible mechanisms underlying the evolution of the nanoheterostructures in liquid media. Representative physical-chemical properties and applications of chemicalization-derived metal-semiconductor nanoheterostructures are emphasized. Finally, prospects for developments in the field are outlined.

Yolk-shell structured magnetic mesoporous organosilica supported ionic liquid/Cu complex: an efficient nanocatalyst for the green synthesis of pyranopyrazoles

The preparation of yolk-shell structured magnetic mesoporous composites is a significant subject between researchers. Especially, modification of theses composites with ionic liquid/metal complex is very important for catalytic processes. In the present study, a novel magnetic methylene-based periodic mesoporous organosilica (PMO)-supported ionic liquid/Cu complex with yolk-shell structure (YS-Fe3O4@PMO/IL-Cu) was prepared via the soft template-assisted method. The TGA, FT-IR, SEM, EDX, XRD, VSM, nitrogen-sorption, and ICP techniques were employed to identify YS-Fe3O4@PMO/IL-Cu. The YS-Fe3O4@PMO/IL-Cu material was applied as a powerful nanocatalyst for the synthesis of pyranopyrazoles under ultrasonic media. The study demonstrated that the YS-Fe3O4@PMO/IL-Cu nanocatalyst is highly recyclable, selective, and effective. The leaching test was performed to investigate the nature of the designed catalyst under the applied conditions.

Biomedical,clinical and environmental applications of platinum-based nanohybrids: An updated review

Platinum nanoparticles (Pt NPs) have numerous applications in various sectors, including pharmacology, nanomedicine, cancer therapy, radiotherapy, biotechnology and environment mitigation like removal of toxic metals from wastewater, photocatalytic degradation of toxic compounds, adsorption, and water splitting. The multifaceted applications of Pt NPs because of their ultra-fine structures, large surface area, tuned porosity, coordination-binding, and excellent physiochemical properties. The various types of nanohybrids (NHs) of Pt NPs can be fabricated by doping with different metal/metal oxide/polymer-based materials. There are several methods to synthesize platinum-based NHs, but biological processes are admirable because of green, economical, sustainable, and non-toxic. Due to the robust physicochemical and biological characteristics of platinum NPs, they are widely employed as nanocatalyst, antioxidant, antipathogenic, and anticancer agents. Indeed, Pt-based NHs are the subject of keen interest and substantial research area for biomedical and clinical applications. Hence, this review systematically studies antimicrobial, biological, and environmental applications of platinum and platinum-based NHs, predominantly for treating cancer and photo-thermal therapy. Applications of Pt NPs in nanomedicine and nano-diagnosis are also highlighted. Pt NPs-related nanotoxicity and the potential and opportunity for future nano-therapeutics based on Pt NPs are also discussed.

Pulsed sonodynamic therapy of melanoma cancer cells using nanoparticles of and mesoporous platinum

OBJECTIVE

Noble metal nanomaterials have been introduced as ideal sonosensitizers for sonodynamic therapy (SDT) of cancer. In this research, platinum nanoparticles (PtNPs) and mesoporous platinum (MPt) were first synthesized and then evaluated as novel sonosensitizers.

METHODS

Ultrasound waves were radiated at two different power densities and two different pulse ratios to develop a pulsed radiation route for SDT of the malignant melanoma cell line C540 (B16/F10). Fluorescence emission was recorded as an indicator of intracellular reactive oxygen generation during the treatment.

RESULTS

Platinum nanoparticles had an average diameter of 12 ± 7 nm and a zeta potential of -17.6 mV; also, MPt had a sponge-like and highly porous structure with a pore size <11 nm and a zeta potential of -39.5 mV. Both PtNPs and MPt, particularly the latter, enhanced the rate of inhibition of tumor cell growth on ultrasound radiation at an output power density of 1.0 W cm^-2 and pulse ratio of 30% over 10 min without intensifying temperature.

CONCLUSION

Use of the developed pulsed (rather than continuous) radiation in SDT and PtNPs or MPT, without hyperthermia, resulted in a new effective cancer treatment method based on the mechanisms of cavitation and/or ROS generation.

Design and Evaluation of Composite Magnetic Iron-Platinum Nanowires for Targeted Cancer Nanomedicine

The purpose of the study was to synthesize and investigate the influence of geometrical structure, magnetism, and cytotoxic activity on core-shell platinum and iron-platinum (Fe/Pt) composite nanowires (NWs) for potential application in targeted chemotherapeutic approaches. The Pt-NWs and Fe/Pt composite NWs were synthesized via template electrodeposition, using anodic aluminum oxide (AAO) membranes. The Fe/Pt composite NWs (Method 1) was synthesized using two electrodeposition steps, allowing for greater control of the diameter of the NW core. The Fe/Pt composite NWs (Method 2) was synthesized by pulsed electrodeposition, using a single electrolytic bath. The properties of the synthesized NWs were assessed by high-resolution transmission electron microscopy (HRTEM), Raman spectroscopy, powder X-ray diffraction (XRD), inductively coupled plasma-optical emission spectrometry (ICP-OES), vibrating-sample magnetometry (VSM), and surface charge (zeta potential). A microscopy image analysis of the NWs revealed the presence of high-aspect-ratio NWs with nominal diameters of 40-50 nm and lengths of approximately <4 µm. The obtained powder XRD patterns confirmed the presence of a polycrystalline structure for both Pt NWs and Fe/Pt composite NWs. The potential utility of the synthesized NW nanoplatforms for anticancer activity was investigated using Tera 1 cells and Mouse 3T3 cells. Pt-NWs displayed modest cytotoxic activity against Tera 1 cells, while the Fe/Pt composite NWs (both Methods 1 and 2) demonstrated enhanced cytotoxic activity compared to the Pt-NWs on Tera 1 cells. The Fe/Pt composite NWs (Method 1) displayed ferromagnetic behavior and enhanced cytotoxic activity compared to Pt-NWs on Tera 1 cells, thus providing a sound basis for future magnetically targeted chemotherapeutic applications.

Nanosized Janus AuNR-Pt Motor for Enhancing NIR-II Photoacoustic Imaging of Deep Tumor and Pt2+ Ion-Based Chemotherapy

Synthetic micro/nanomotors have great potential in deep tissue imaging and in vivo drug delivery because of their active motion ability. However, applying nanomotors with a size less than 100 nm to in vivo imaging and therapy is one of the core changes in this field. Herein, a nanosized hydrogen peroxide (H₂O₂)-driven Janus gold nanorod-platinum (JAuNR-Pt) nanomotor is developed for enhancing the second near-infrared region (NIR-II) photoacoustic (PA) imaging of deep tissues of tumors and for effective tumor treatment. The JAuNR-Pt nanomotor is prepared by depositing platinum (Pt) on one end of a gold nanorod with varying proportions of Pt shell coverage, including 10%, 25%, 50%, 75%, and 100%. The JAuNR-Pt nanomotor with Pt shell coverage proportions of 50% exhibits the highest diffusion coefficient (D_e), and it can rapidly move in the presence of H₂O₂. The self-propulsion of JAuNR-Pt nanomotor enhances cellular uptake, accelerates lysosomal escape, and facilitates continuous release of cytotoxic Pt²⁺ ions to the nucleus, causing DNA damage and cell apoptosis. The JAuNR-Pt nanomotor presents deep penetration and enhanced accumulation in tumors as well as high tumor treatment effect. Therefore, this work displays deep tumor imaging and an excellent antitumor effect, providing an effective tool for accurate diagnosis and treatment of diseases.

Synthetic Approaches to Colloidal Nanocrystal Heterostructures Based on Metal and Metal-Oxide Materials

Composite inorganic nanoarchitectures, based on combinations of distinct materials, represent advanced solid-state constructs, where coexistence and synergistic interactions among nonhomologous optical, magnetic, chemical, and catalytic properties lay a basis for the engineering of enhanced or even unconventional functionalities. Such systems thus hold relevance for both theoretical and applied nanotechnology-based research in diverse areas, spanning optics, electronics, energy management, (photo)catalysis, biomedicine, and environmental remediation. Wet-chemical colloidal synthetic techniques have now been refined to the point of allowing the fabrication of solution free-standing and easily processable multicomponent nanocrystals with sophisticated modular heterostructure, built upon a programmed spatial distribution of the crystal phase, composition, and anchored surface moieties. Such last-generation breeds of nanocrystals are thus composed of nanoscale domains of different materials, assembled controllably into core/shell or heteromer-type configurations through bonding epitaxial heterojunctions. This review offers a critical overview of achievements made in the design and synthetic elaboration of colloidal nanocrystal heterostructures based on diverse associations of transition metals (with emphasis on plasmonic metals) and transition-metal oxides. Synthetic strategies, all leveraging on the basic seed-mediated approach, are described and discussed with reference to the most credited mechanisms underpinning regioselective heteroepitaxial deposition. The unique properties and advanced applications allowed by such brand-new nanomaterials are also mentioned.

Advances in FePt-involved nano-system design and application for bioeffect and biosafety

The rapid development and wide application of nanomaterial-involved theranostic agents have drawn surging attention for improving the living standard of humankind and healthcare conditions. In this review, recent developments in the design, synthesis, biocompatibility evaluation and potential nanomedicine applications of FePt-involved nano-systems are summarized, especially for cancer theranostic and biological molecule detection. The in vivo multi-model imaging capability is discussed in detail, including magnetic resonance imaging and computed tomography. Furthermore, we highlight the significant achievements of various FePt-involved nanotherapeutics for cancer treatment, such as drug delivery, chemodynamic therapy, photodynamic therapy, radiotherapy and immunotherapy. In addition, a series of FePt-involved nanocomposites are also applied for biological molecule detection, such as H₂O₂, glucose and naked-eye detection of cancer cells. Ultimately, we also summarize the challenges and prospects of FePt-involved nano-systems in nanocatalytic medicine. This review is expected to give a general pattern for the development of FePt-involved nano-systems in the field of nanocatalytic medicine and analytical determination.

Rapid microwave-assisted biosynthesis of platinum nanoparticles and evaluation of their antioxidant properties and cytotoxic effects against MCF-7 and A549 cell lines

In this study, platinum nanoparticles (Pt NPs) were synthesized by a green method using an aqueous extract of Eucalyptus camaldulensis with assistance of microwave irradiation (850 W) and their physicochemical characteristics were studied by UV-visible spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR) analyses. Antioxidant activities, hemocompatibility, and cytotoxic effects of the prepared Pt NPs were then evaluated. The attained results showed that the newly formed Pt NPs possess a size range between 7.4 and 11.2 nm. These spherical-shaped NPs were slightly aggregated and held various functional groups on their surface. The antioxidant activity of Pt nanostructures was comparable to that of butylated hydroxyl anisole at concentrations higher than 320 µg/mL. At the same concentration of 640 μg/mL, the scavenging activities were 3.36 ± 0.9% (hexachloroplatinic acid) and 52.13 ± 0.43% (Pt NPs). The results of hemolytic assay revealed satisfactory hemocompatibility of the Pt NPs even at the concentration as high as 4 mg/mL (hemolysis percent equal to 3.5 ± 1.3%). The cytotoxicity studies revealed that MCF-7, A549, and 3T3 cell lines treated with hexachloroplatinic acid and cisplatin for 24 h and 48 h showed a higher percentage of cell death compared with the Pt NPs. After 24 h, for A549, 3T3, and MCF-7 cells exposed to Pt NPs, the cell viability was measured to be 80 ± 3.2%, 96 ± 1%, and 89 ± 2.6%, respectively, at concentration of 640 µg/mL. Further investigations are required to elucidate the mechanisms behind the biological activities of as-synthesized Pt NPs.

Biomimetic Platform Based on Mesoporous Platinum for Multisynergistic Cancer Therapy

Photothermal therapy (PTT) using nanoparticles is one of the research hotspots in the field of cancer therapy. However, the thermal resistance of tumor cells and the elimination of nanoparticles by the body's immune system reduce their therapeutic effect. Therefore, it is essential to reduce heat resistance, improve their biocompatibility, and reduce the clearance of the immune system. In this work, we constructed a biomimetic platform for cancer therapy based on heat shock protein (HSP) inhibitors, 17-dimethylaminoethylamino-17-demethoxygeldanamycin (17-DMAG))-loaded and platelet membrane (PM)-coated mesoporous platinum nanoparticles (MPNPs). First, MPNPs with the properties of chemotherapy and PTT were synthesized to load 17-DMAG (17-DMAG/MPNPs). Then, they were coated with PM for tumor targeting and improved biocompatibility to obtain the final bionic nanotherapy platform 17-DMAG/MPNPs@PM. The results in vivo and in vitro showed that 17-DMAG/MPNPs@PM could accumulate in the tumor and effectively inhibit the growth of tumor cells. Therefore, the biomimetic nanotherapy system is expected to provide new ideas for cancer treatment.

Porous Cobalt Sulfide Selenium Nanorods for Electrochemical Hydrogen Evolution

A key process in electrochemical energy technology is hydrogen evolution reaction (HER). However, its electrochemical properties mainly depend on the catalytic activity of the material itself. Therefore, it is important to find efficient electrocatalysts to realize clean hydrogen production. As a typical kind of catalytic materials, transition metal dichalcogenides (TMCs) play important roles in the field of energy catalysis. As a representative of TMCs, cobalt disulfide (CoS₂), recently has raised much research interest owing to its abundant reserves, environmental friendliness, and excellent electrochemical stability. Meanwhile, given the fact that doping is one of the effective methods to improve the electrochemical catalytic property, various means of doping have been researched. Here, we report for the first time that porous-like Se-CoS_2-x (or Se:CoS_2-x ) nanorod can be facilely synthesized via a controllable two-step strategy. It is demonstrated that doping Se can greatly improve the catalytic performance of CoS₂ electrode. The electrode can obtain a current density of 10 mA cm^-2 at overpotential of only ∼260 mV. And the current changes with the applied bias voltage in an obvious stepped pattern, in the chronopotential (CP) curve of Se-CoS_2-x , indicating its outstanding mass transfer property and mechanical stability.

Combination of starvation therapy and Pt-NP based chemotherapy for synergistic cancer treatment

Platinum nanoparticles (Pt-NPs) have been developed for enhanced toxicity against tumor cells. However, the therapeutic effect of Pt-NPs was severely limited by the lack of cellular uptake of Pt-NPs and an oxidative environment. The combination of starvation therapy with Pt-NP based chemotherapy in a well-designed nano-system is expected to eliminate tumors. Therefore, GOx and Pt-NPs were coated with PLGA to obtain a functional nano-system (GOx-Pt-NS), which increased the cellular uptake of Pt-NPs. The accumulation of GOx-Pt-NS in tumors increased significantly via the enhanced permeability and retention (EPR) effect of nanoparticles. In addition, protection of the GOx-Pt-NS overcame several drawbacks of GOx such as poor stability, short in vivo half-life, immunogenicity, and systemic toxicity. Glucose oxidase (GOx) elevated the gluconic acid ROS levels in tumor cells, resulting in an acidic and oxidative environment. The acidic and oxidative environment enhanced the conversion of Pt²⁺via Pt NPs as well as DNA-binding ability. Finally, combining GOx based starvation therapy with Pt-NP based chemotherapy was expected to eliminate tumors more efficiently through a synergistic strategy.

Zebrafish as a Model for Anticancer Nanomedicine Studies

Nanomedicine is a new approach to fight against cancer by the development of anticancer nanoparticles (NPs) that are of high sensitivity, specificity, and targeting ability to detect cancer cells, such as the ability of Silica NPs in targeting epithelial cancer cells. However, these anticancer NPs require preclinical testing, and zebrafish is a useful animal model for preclinical studies of anticancer NPs. This model affords a large sample size, optical imaging, and easy genetic manipulation that aid in nanomedicine studies. This review summarizes the numerous advantages of the zebrafish animal model for such investigation, various techniques for inducing cancer in zebrafish, and discusses the methods to assess cancer development in the model and to test for the toxicity of the anticancer drugs and NPs. In addition, it summarizes the recent studies that used zebrafish as a model to test the efficacy of several different anticancer NPs in treating cancer.

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

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

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

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

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

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

Formation and Application of Core-Shell of FePt-Au Magnetic-Plasmonic Nanoparticles

Monodispersed FePt core and FePt–Au core–shell nanoparticles (NPs) have been chemically synthesized in liquid solution and with controllable surface-functional properties. The NP size was increased from 2.5 nm for FePt to 6.5 nm for FePt–Au, which could be tuned by the initial concentration of gold acetate coated onto FePt seeding NPs via a seed-mediated formation of self-assembled core–shell nanostructures. The analyses of the interplanar spacing obtained from the high-resolution transmission electron microscopy (HRTEM), selective electron diffraction pattern (SAED), and x-ray diffraction (XRD) confirmed that both FePt core and Au shell belong to the face-centered cubic (fcc) structure. FePt–Au NPs have a surface plasmon resonance (SPR) peak at 528 nm in the visible optical band region, indicating the red shift compared with the typical theoretical value of 520 nm of pure Au NPs. The surface modification and ligand exchange of FePt–Au was using mercaptoacetic acid (thiol) as a phase transfer reagent that turned the NPs hydrophilic due to the functional carboxyl group bond on the surface of presented multifunctional magnetic–plasmonic NPs. The water-dispersible FePt-based NPs conjugated with biomolecules could reach the different biocompatibility requirements and also provide enough heating response that acted as a potential agent for magnetic fluid hyperthermia in biomedical engineering research fields.

Au@Pt Core-Shell Nanoparticle Bioconjugates for the Therapy of HER2+ Breast Cancer and Hepatocellular Carcinoma. Model Studies on the Applicability of 193mPt and 195mPt Radionuclides in Auger Electron Therapy

^193mPt and ^195mPt radionuclides are therapeutically attractive Auger electron emitters with notably high Auger electron yield per decay. The present paper summarizes the first step of research on the applications of core-shell (Au@Pt) nanoparticles for electron Auger therapy of HER2+ (human epidermal growth factor receptor 2) breast cancer and hepatocellular carcinoma. Gold nanoparticles (30 nm) were synthesized covered with a platinum shell at high efficiency (>80%) and were further evaluated for in vitro studies such as binding affinity, internalization and cytotoxicity. To find the mechanism(s) responsible for platinum cytotoxicity in HepG2 cells, the platinum concentration in isolated cell nuclei and cytoplasm was determined using ICP-MS (inductively coupled plasma mass spectrometry). Lack of platinum in cell nuclei suggests that the cytotoxic effect is associated with the generation of reactive oxygen species (ROS) and reactive nitrogen species (RNS). Studies carried out on the SKOV-3 cell line with the use of a synthesized targeting bioconjugate (Au@Pt-PEG-trastuzumab) revealed a high affinity of this preparation to HER2+ cells, its internalization, its placement in the perinuclear area and partial intranuclear location. The specific binding for HER2 negative cells, MDA-MB-231, was negligible and Au@Pt-PEG-trastuzumab did not enter these cells. The results obtained are promising and warrant future investigation of Auger electron therapy using ^193mPt and ^195mPt based radiopharmaceuticals.

Ru-containing magnetic yolk-shell structured nanocomposite: a powerful, recoverable and highly durable nanocatalyst

A novel method was used to prepare a magnetic phenylene-based periodic mesoporous organosilica nanocomposite with yolk-shell structure (Fe3O4@YSPMO). The Fe3O4@YSPMO nanomaterial was prepared by using easily accessible pluronic-P123 and cetyltrimethylammonium bromide (CTAB) surfactants under basic conditions. This material was employed for effective immobilization of potassium perruthenate to prepare an Fe3O4@YSPMO@Ru nanocatalyst for the aerobic oxidation of alcohols. The physiochemical properties of the designed Fe3O4@YSPMO@Ru nanocomposite were studied using PXRD, FT-IR, TGA, SEM, TEM, ICP, VSM and XPS analyses. Fe3O4@YSPMO@Ru was effectively employed as a highly recoverable nanocatalyst in the selective aerobic oxidation of alcohols.

Nanoparticle-delivered miriplatin ultrasmall dots suppress triple negative breast cancer lung metastasis by targeting circulating tumor cells

No effective therapy is yet available to treat triple negative breast cancer (TNBC), which has poor prognosis due to frequent metastasis. Cancer stem cells (CSCs) or CSC-like cells play crucial roles in cancer metastasis and are exceptionally tolerant with genetic lesions. The extent of DNA damages has an important impact on the fate of CSCs. Despite the importance of platinum [Pt(II)] agents in cancer therapy, accumulating reports showed the treatment failure of conventional Pt(II) drugs, which is likely due to their inadequate DNA damage effects. Miriplatin is a clinically approved drug only being locally-used for treating liver cancer. In this study, we developed a novel ultrasmall Pt(II) dot (uPtD) from miriplatin and encapsulated it into our recently-reported integrin α5(ITGA5) active targeting nanoparticles (uPtDs NPs) and tested their therapeutic efficacy against TNBC metastasis. It was found that uPtDs NPs displayed a superior DNA damage capability via enhanced-interactions with DNA and a significantly stronger effect in reducing CSC-like property of TNBC cells, compared to conventional cisplatin and miriplatin. Mechanistically, the severe DNA damages induced by uPtDs NPs activated the CHK_1/2-CDC25A-cyclin A/E pathway to induce cell cycle arrest. Moreover, uPtDs NPs could target the in vivo circulating tumor cells (CTCs) to suppress TNBC lung metastasis. Given the desired-safety profile of miriplatin, the uPtDs represent a promising therapeutic agent of the metal-based nanomedicines to reduce cancer metastasis. SIGNIFICANCE: The miriplatin ultrasmall dots developed from clinically-prescribed miriplatin may serve as a potent systemically-administered agent to target CTCs and reduce cancer metastasis.

Near Infrared-Activatable Platinum-Decorated Gold Nanostars for Synergistic Photothermal/Ferroptotic Therapy in Combating Cancer Drug Resistance

Ferroptotic cell death results from glutathione peroxidase 4 (GPX4) inactivation and/or glutathione (GSH) depletion. Elevated GSH levels are often found in multidrug-resistant (MDR) tumor cells, reducing their sensitivity to chemotherapeutic drugs and the efficacy of treatment. MDR cells also acquire a dependency on GPX4, reducing their oxidative stress and promoting their survival. Therefore, the depletion of GSH and inactivation of GPX4 has the potential to be a superior treatment strategy for MDR tumors. Platinum-decorated gold nanostars (Pt-AuNS) are presented as a novel metal nanoprodrug for ferroptotic therapy against MDR tumors. Under dark conditions, the synthesized Pt-AuNS exhibit negligible levels of toxicity. Upon exposure of the Pt-AuNS to near-infrared (NIR) light, active metallic (Pt and Au) species are released, subsequently inducing cytotoxicity. The mechanism of action is attributed to GSH depletion and GPX4 inactivation, accumulating lipid hydroperoxides, which in turn leads to ferroptosis. In in vivo xenograft, the MDR cancer model confirmed the NIR light-activation of Pt-AuNS prodrugs, resulting in efficient ferroptotic therapeutic action against MDR tumors without long-term side effects. The findings lay the groundwork for using Pt-AuNS prodrugs responsive to NIR light as ferroptosis-inducing agents in chemo-resistant cancer cells and demonstrate their potential for use in future clinical applications.

Droplet-Splitting Microchip Online Coupled with Time-Resolved ICPMS for Analysis of Released Fe and Pt in Single Cells Treated with FePt Nanoparticles

The intracellular release of Fe/Pt ions from FePt nanoparticles (NPs) in single cells is highly critical to elucidate the potential cytotoxicity or potential cell protection mechanism of FePt NPs. For the first time, the quantitative analysis of Fe/Pt released from FePt-Cys NPs in single cells was achieved by a droplet-splitting microchip coupled online to inductively coupled plasma mass spectrometry detection. The droplet-splitting chip integrates droplet generation, cell lysis, and droplet-splitting units. The quantification of released Fe/Pt was achieved via measuring standard Fe/Pt ionic solutions. For the determination of total Fe/Pt in single cells, the same microchip with different operation modes (total-mode) was used, and the quantification of total Fe/Pt was achieved with FePt NPs as the standard. The developed method with two analysis modes was applied to study the decomposition behavior of FePt-Cys NPs in single cells, and the results indicated that the percentages of the cells absorbing/decomposing FePt-Cys NPs increased with the incubation time. Almost all cells absorbed FePt-Cys NPs after 6 h, while only about 60% cells decomposed FePt-Cys NPs after 6 h and almost all cells decomposed FePt-Cys NPs after 18 h. Besides, the released Fe content was lower than its endogenous content in cells and the release rate of Pt was higher than that of Fe, providing a possibility that the released Pt may contribute more to cytotoxicity. The developed system enabled fractionation of Fe/Pt in single cells treated with FePt NPs with high accuracy, easy operation, and high throughput and showed a great potential for elemental speciation at the single-cell level.

Controlled anti-cancer drug release through advanced nano-drug delivery systems: Static and dynamic targeting strategies

Advances in nanomedicine, including early cancer detection, targeted drug delivery, and personalized approaches to cancer treatment are on the rise. For example, targeted drug delivery systems can improve intracellular delivery because of their multifunctionality. Novel endogenous-based and exogenous-based stimulus-responsive drug delivery systems have been proposed to prevent the cancer progression with proper drug delivery. To control effective dose loading and sustained release, targeted permeability and individual variability can now be described in more-complex ways, such as by combining internal and external stimuli. Despite these advances in release control, certain challenges remain and are identified in this research, which emphasizes the control of drug release and applications of nanoparticle-based drug delivery systems. Using a multiscale and multidisciplinary approach, this study investigates and analyzes drug delivery and release strategies in the nanoparticle-based treatment of cancer, both mathematically and clinically.

One-pot synthesis of highly active and hydrothermally stable Pd@mHSiO2 yolk-shell-structured nanoparticles for high-temperature reactions in hydrothermal environments

The facile synthesis of yolk-shell-structured nanoparticles (YSNPs) with mobile active metal cores and mesoporous inorganic-organic hybrid silica shells (mHSiO2) is important for their applications. In this work, Pd@mHSiO2 YSNPs have been synthesized in aqueous solution at 95 °C by a one-pot method without the need for extensive purification and separation steps. The method is simple and facile, and ingeniously combines the controlled synthesis of Pd nanocubes, coating of mesoporous silica, and transition from core-shell-structured nanoparticles (CSNPs) to YSNPs. 29Si NMR spectroscopy, FTIR spectroscopy, and detailed control experiments have demonstrated that the incorporation of 1,2-bis(trimethoxysilyl)ethane (BTME) modifies the degree of condensation between the outer hybrid silica layer and the inner pure silica section, and that high temperature water is really responsible for dissolving the inner pure silica layer leading to a transition from the CSNPs to the YSNPs. The obtained Pd@mHSiO2 YSNPs have a controllable diameter, tunable shell thickness, a high specific surface area, and uniform mesoporosity. Thermal stability tests have indicated that the Pd@mHSiO2 YSNPs are remarkably stable at high temperatures up to 650 °C. Importantly, the Pd@mHSiO2 YSNPs exhibit a much higher catalytic activity and hydrothermal stability than Pd@mSiO2 CSNPs or Pd/mHSiO2 NSs in the conversion of levulinic acid (LA) into γ-valerolactone (GVL), because the hollow voids provide low mass-transfer resistance and improve the accessibility of the catalytic sites, and the incorporation of organic groups enhances the hydrothermal stability of the outer shell.

Programmed co-delivery of platinum nanodrugs and gemcitabine by a clustered nanocarrier for precision chemotherapy for NSCLC tumors

A pH/redox dual stimuli-responsive clustered nanoparticles are demonstrated as vehicle for simultaneously delivering ultra-small platinum nanoparticles (USPtNs) and gemcitabine (GEM) to treat non-small-cell lung cancer.

Rational design of yolk–shell nanostructures for drug delivery

The recent progress in yolk–shell nanoparticles (YSNPs) as a new class of hollow nanostructures applied for drug delivery.

Nanomaterials and nanocomposite applications in veterinary medicine

Nowadays, nanotechnology has made huge, significant advancements in biotechnology and biomedicine related to human and animal science, including increasing health safety, production, and the elevation of national income. There are various fields of nanomaterial applications in veterinary medicine such as efficient diagnostic and therapeutic tools, drug delivery, animal nutrition, breeding and reproduction, and valuable additives. Additional benefits include the detection of pathogens, protein, biological molecules, antimicrobial agents, feeding additives, nutrient delivery, and reproductive aids. There are many nanomaterials and nanocomposites that can be used in nanomedicine such as metal nanoparticles, liposomes, carbon nanotubes, and quantum dots. In the near future, nanotechnology research will have the ability to produce novel tools for improving animal health and production. Therefore, this chapter was undertaken to spotlight novel methods created by nanotechnology for application in the improvement of animal health and production. In addition, the toxicity of nanomaterials is fully discussed to avoid the suspected health hazards of toxicity for animal health safety.

A Comprehensive Review on the Synthesis, Characterization, and Biomedical Application of Platinum Nanoparticles

Platinum nanoparticles (PtNPs) are noteworthy scientific tools that are being explored in various biotechnological, nanomedicinal, and pharmacological fields. They are unique because of their large surface area and their numerous catalytic applications such as their use in automotive catalytic converters and as petrochemical cracking catalysts. PtNPs have been widely utilized not only in the industry, but also in medicine and diagnostics. PtNPs are extensively studied because of their antimicrobial, antioxidant, and anticancer properties. So far, only one review has been dedicated to the application of PtNPs to nanomedicine. However, no studies describe the synthesis, characterization, and biomedical application of PtNPs. Therefore, the aim of this review is to provide a comprehensive assessment of the current knowledge regarding the synthesis, including physical, chemical, and biological and toxicological effects of PtNPs on human health, in terms of both in vivo and in vitro experimental analysis. Special attention has been focused on the biological synthesis of PtNPs using various templates as reducing and stabilizing agents. Finally, we discuss the biomedical and other applications of PtNPs.

Study on the dissolution of hollow mesoporous silica nanosphere-supported nanosized platinum oxide in biorelevant media for evaluating its potential as chemotherapeutics

Platinum oxide (PtO_x) nanoparticles (NPs) have been shown to possess anticancer activity by releasing ionic Pt species under biological conditions. However, the dissolution kinetics and the changes in the chemical state of Pt during PtO_x dissolution have not yet been studied. To fill this gap, we prepared a composite (designated as PtO_x@MMT-2) containing PtO_x NPs on hollow mesoporous silica nanospheres and studied the dissolution of the material in different biorelevant media. We found that the release of Pt was retarded due to the adsorption of biomolecules on PtO_x NPs during the degradation of host silica. The biomolecules adsorption also lowered the accessibility of PtO_x NPs, resulting in the reduced catalase-like activity of the NPs. In line with the results, the cytotoxicity of PtO_x@MMT-2, which was positively correlated to the amount of Pt uptake, was reduced by biomolecules adsorption. Our findings should be applicable to other metal (oxide) NPs under biological conditions and may provide implications for the design of nanomaterials for practical therapeutic applications.

Synthesis and Electrochemical Energy Storage Applications of Micro/Nanostructured Spherical Materials

Micro/nanostructured spherical materials have been widely explored for electrochemical energy storage due to their exceptional properties, which have also been summarized based on electrode type and material composition. The increased complexity of spherical structures has increased the feasibility of modulating their properties, thereby improving their performance compared with simple spherical structures. This paper comprehensively reviews the synthesis and electrochemical energy storage applications of micro/nanostructured spherical materials. After a brief classification, the concepts and syntheses of micro/nanostructured spherical materials are described in detail, which include hollow, core-shelled, yolk-shelled, double-shelled, and multi-shelled spheres. We then introduce strategies classified into hard-, soft-, and self-templating methods for synthesis of these spherical structures, and also include the concepts of synthetic methodologies. Thereafter, we discuss their applications as electrode materials for lithium-ion batteries and supercapacitors, and sulfur hosts for lithium–sulfur batteries. The superiority of multi-shelled hollow micro/nanospheres for electrochemical energy storage applications is particularly summarized. Subsequently, we conclude this review by presenting the challenges, development, highlights, and future directions of the micro/nanostructured spherical materials for electrochemical energy storage.

Size-Tailored Biocompatible FePt Nanoparticles for Dual T1/T2 Magnetic Resonance Imaging Contrast Enhancement

The development of new contrast agents (CAs) for magnetic resonance imaging (MRI) is of high interest, especially because of the increased concerns of patient safety and quick clearance of clinically used gadolinium and iron oxide-based CAs, respectively. Here, a two-step synthesis of superparamagnetic water-soluble iron platinum (FePt) nanoparticles (NPs) with core sizes between 2 and 8 nm for use as CAs in MRI is reported. First, wet-chemical organometallic NPs are synthesized by thermal decomposition in the presence of stabilizing oleic acid and oleylamine. Second, the hydrophobic NPs are coated with an amphiphilic polymer and transferred into aqueous media. Their magnetization values and relaxation rates exceed those published for CAs already used for clinical application. Their saturation magnetization increases with the core size to approximately 82 A·m²/kg_Fe. For 8 nm NPs, the T₂ relaxivity of approximately 221 (mM·s)^-1 is 5 times larger than that for the ferumoxides, and for 6 nm NPs, the T₁ relaxivity of approximately 12 (mM·s)^-1 is slightly higher than that of ultrasmall gadolinium oxide NPs. The 6 nm FePt NPs are identified as excellent CAs for both T₁ and T₂ imaging. Most importantly, because of their coating, significantly low cytotoxicity is achieved. FePt NPs prove to be a promising alternative to gadolinium and iron oxide NPs showing high-quality CA characteristics for both T₁- and T₂-weighted images.

Spatiotemporally Light-Activatable Platinum Nanocomplexes for Selective and Cooperative Cancer Therapy

Highly efficient nanoarchitectures are of great interest for achieving precise chemotherapy with minimized adverse side effects in cancer therapy. However, a major challenge remains in exploring a rational approach to synthesize spatiotemporally selective vehicles for precise cancer chemotherapy. Here, we demonstrate a rational design of bifunctional light-activatable platinum nanocomplexes (PtNCs) that produce dually cooperative cancer therapy through spatiotemporally selective thermo-chemotherapy. The Pt⁴⁺-coordinated polycarboxylic nanogel is explored as the nanoreactor template, which is exploited to synthesize bifunctional PtNCs consisting of a zero-valent Pt⁰ core and a surrounding bivalent Pt²⁺ shell with tunable ratios through a facile and controllable reduction. Without light exposure, chemotherapeutic Pt²⁺ ions are tightly bound on the surface of PtNCs, efficiently reducing undesirable drug leakage and nonselective damage on normal tissues/cells. Upon light exposure, PtNCs generate much heat via photothermal conversion from the Pt⁰ core and simultaneously trigger a rapid release of chemotherapeutic Pt²⁺ ions, thereby leading to the spatiotemporally light-activatable synergistic effect of thermo-chemotherapy. Moreover, PtNCs show enhanced tumor accumulation through the heat-triggered hydrophilicity-hydrophobicity transition upon immediate light exposure after injection, dramatically facilitating in vivo tumor regression through their cooperative anticancer efficiency. This rational design of spatiotemporally activatable nanoparticles provides an insightful tool for precise cancer therapy.

Peptide-Based Autophagic Gene and Cisplatin Co-delivery Systems Enable Improved Chemotherapy Resistance

Cisplatin-based chemotherapy is a widely used first-line strategy for numerous cancers. However, drug resistances are often inevitable accompanied by the long-term use of cisplatin in vivo, significantly hampering its therapeutic efficacy and clinical outcomes. Among others, autophagy induction is one of the most common causes of tumor resistance to cisplatin. Herein, a self-assembled nanoprodrug platform was developed with the synergistic effect of cisplatin and RNAi to fight against cisplatin-resistant lung cancer. The nanoprodrug platform consists of three molecular modules, including prodrug complex of Pt(IV)-peptide-bis(pyrene), DSPE-PEG, and cRGD-modified DSPE-PEG. The Pt(IV) is immobilized with peptide via amide bonds, allowing the Pt(IV) to be loaded with a loading efficiency of >95% and rapid-release active platinum ions (Pt(II)) in the presence of glutathione (GSH). Meanwhile, the peptide of the prodrug complex could efficiently deliver Beclin1 siRNA ( Beclin1 is an autophagy initiation factor) to the cytoplasm, thereby leading to autophagy inhibition. In addition, incorporation of DSPE-PEG and cRGD-modified DSPE-PEG molecules improves the biocompatibility and cellular uptake of the nanoprodrug platform. In vivo results also indicate that the nanoprodrug platform significantly inhibits the growth of a cisplatin-resistant tumor on xenograft mice models with a remarkable inhibition rate, up to 84% after intravenous injection.

Near-Infrared Responsive Bimetallic Nanovesicles for Enhanced Synergistic Chemophotothermal Therapy

Limited therapeutic effects and obvious side effects are two critical problems affecting tumor therapy. Herein, we designed an ingenious nanocarrier, platinum/gold bimetallic-nanoshell-coated triptolide liposomes (Pt@Au-TP-Lips), to achieve enhanced chemophotothermal therapy against cancer. Compared to conventional gold nanoflower structures, the platinum/gold bimetallic (Pt@Au) core-shells exhibited broader near-infrared (NIR) absorption due to the ultrastrong plasmonic coupling effect. With NIR light irradiation, the Pt@Au nanostructure could efficiently and sustainably convert light energy into substantial heat. The ultrahigh photothermal conversion efficiency (56.5%) of Pt@Au-TP-Lips was significantly higher than that of gold nanoflowers (35.7%). Specifically, hyperthermia could induce a phase change in the liposome membrane to accelerate the release of triptolide (TP); meanwhile, it could ablate tumor cells directly and facilitate the cellular uptake of drugs to enhance chemotherapy. More importantly, owing to the cooperation of TP and platinum, Pt@Au-TP-Lips exhibited significant tumor growth suppression with a high inhibitory rate of 90.7%, achieving superior chemophotothermal combination therapy. This work provides new insight into the development of a cooperative theranostic agent for oncotherapy.

Synthesis, characterization, and environmental behaviors of monodispersed platinum nanoparticles

The release of platinum group elements, including platinum nanoparticles (PtNPs), has been increasing over recent decades. However, few studies have investigated the fate, behavior and effects of PtNPs in environmental media. Here, we report a protocol for the synthesis of five different sizes (8.5 ± 1.2, 10.3 ± 1.3, 20.0 ± 4.8, 40.5 ± 4.1, and 70.8 ± 4.2 nm) of monodispersed citrate- and polyvinylpyrrolidone (PVP)-coated PtNPs, together with a characterization of their behaviors using a multi method approach in relevant biological and toxicological media. In general, PtNPs sizes measured using dynamic light scattering, field flow fractionation, single-particle inductively-coupled plasma-mass spectroscopy, transmission electron microscopy and atomic force microscopy, were all in good agreement when PtNP sizes were larger than the size detection limits of each analytical technique. Slight differences in sizes measured were attributable to differences in analytical techniques, measuring principles, NP shape and NP permeability. The thickness of the PVP layer increased (from 4.4 to 11.35 nm) with increases in NP size. The critical coagulation concentration of cit-PtNPs was independent of NP size, possibly due to differences in PtNPs surface charges as a function of NP size. PtNPs did not undergo significant dissolution in any media tested. PtNPs did not aggregate significantly in Dulbecco's modified Eagle's medium; but they formed aggregates in moderately hard water and in 30 ppt synthetic seawater, and aggregate size increased with increases in PtNPs concentration. Overall, this study describes a general model NP system (i.e., PtNPs) of different controlled NP sizes and coatings that is predictable, stable and useful to investigate the fate, behavior, uptake, and eco-toxicity of NPs in the environment.

Rational design of yolk–shell nanostructures for photocatalysis

Yolk–shell structures provide an ideal platform for the rational regulation and effective utilization of charge carriers because of their void space and large surface areas. Furthermore, the efficiency of charge behavior in every step can be further improved by many strategies. This review describes the synthesis of yolk–shell structures and their effect for the enhancement of heterogeneous photocatalysis.

Anti-tumour activity of low molecular weight heparin doxorubicin nanoparticles for histone H1 high-expressive prostate cancer PC-3M cells

Nucleus-targeting drug delivery systems (NTDDs) deliver chemotherapeutic agents to nuclei in order to improve the efficacy of anti-tumour therapy. Histone H1 (H1) plays a key role in establishing and maintaining higher order chromatin structures and could bind to cell membranes. In the present study, we selected H1 as a target to prepare a novel H1-mediated NTDD. Low molecular weight heparin (LMHP) and doxorubicin (DOX) were combined to form LMHP-DOX. Then, a novel NTDD consisting of LMHP-DOX nanoparticles (LMHP-DOX NPs) was prepared by self-assembly. The characteristics of LMHP-DOX and LMHP-DOX NPs were investigated. Histone H1 high-expressive prostate cancer PC-3M cell line was selected as the cell model. Cellular uptake, and the in vitro and in vivo anti-tumour activity of LMHP-DOX NPs were evaluated on H1 high-expressive human prostate cancer PC-3M cells. Our results indicated that intact LMHP-DOX NPs mediated by H1 could be absorbed by H1 high-expressive PC-3M cells, escape from the lysosomes to the cytoplasm, and localize in the perinuclear region via H1-mediated, whereby DOX could directly enter the cell nucleus and quickly increase the concentration of DOX in the nuclei of H1 high-expressive PC-3M cells to enhance the apoptotic activity of cancer cells. The anti-coagulant activity of LMHP-DOX NPs was almost completely diminished in rat blood compared with that of LMHP, indicating the safety of LMHP-DOX NPs. Compared to traditional NTDD strategies, LMHP-DOX NPs avoid the complicated modification of nucleus-targeting ligands and provide a compelling solution for the substantially enhanced nuclear uptake of chemotherapeutic agents for the development of more intelligent NTDDs.

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.

Magnetofluorescent nanohybrid comprising polyglycerol grafted carbon dots and iron oxides: Colloidal synthesis and applications in cellular imaging and magnetically enhanced drug delivery

Multifunctional nanohybrids are attracting increasing attention for potential biomedical applications such as bioimaging and drug delivery due to their combined advantages of individual components. However, challenges in the improvement of their synthesis and colloidal stability to facilitate practical biomedical applications still remain. In this work, we report an efficient synthetic approach to fabricate magnetofluorescent nanohybrid (IO-PG-CD) comprising fluorescent carbon dots (CDs) and magnetic iron oxide nanoparticles (IOs) through polyglycerol (PG) mediated covalent linkage in aqueous media. CDs and IOs are first grafted with PG layer, and then functionalized with carboxyl and amino groups, respectively. The resulting CD-PG-COOH and IO-PG-NH₂ handled as simple chemical compounds are integrated through EDC/NHS crosslinking to obtain the desired IO-PG-CD nanohybrid. The unprecedented hydrophilicity of PG layer endows IO-PG-CD nanohybrid with excellent colloidal stability in various physiological media, facilitating biomedical applications in vitro and in vivo. IO-PG-CD nanohybrid exhibits low cytotoxicity and its uptake by cells can be obviously enhanced by external magnetic attraction. The internalized IO-PG-CD nanohybrid emits multicolor fluorescence as observed by confocal fluorescence microscopy, demonstrating much better photostability than the nanoparticle labeled with organic dye. Taking advantage of enormous chelating carboxyl groups on the surface of IO-PG-CD nanohybrid, platinum-based anticancer drug was loaded on the surface (IO-PG-CD/Pt) through complexation and delivered into cancer cells in a magnetically enhanced manner, killing the cancer cells efficiently in vitro. Moreover, in vivo cancer therapy indicates that the external magnetic attraction also obviously improves the anticancer efficacy of IO-PG-CD/Pt in HeLa subcutaneous xenografts.

Design and synthesis of magnetic nanoparticles for biomedical diagnostics

Sensitive and quantitative characterization of clinically relevant biomarkers can facilitate disease diagnosis and treatment evaluation. Magnetic nanomaterials and their biosensing strategies have recently received considerable attention. Magnetic signals experience little interference from native biological background as most biological molecules have negligible magnetic susceptibilities and thus appear transparent to external magnetic fields. Because of this unique property, magnetic sensing can be applied to both in vivo deep tissue imaging as well as ex vivo point-of-care diagnostics. To exploit this mode of magnetic detection, new advancements in both magnetic material syntheses and sensing technologies have been made. This review focuses on recent developments of magnetic nanomaterials as image contrast agents and diagnostic sensors. These developments have not only enabled precise control of magnetic nanomaterial properties but also expanded the reach of magnetic detection for biomedical diagnostics.