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1.
Transition metal‐based nanoparticles have shown their broad applications in versatile biomedical applications. Although traditional iron‐based nanoparticles have been extensively explored in biomedicine, transition metal manganese (Mn)‐based nanoparticulate systems have emerged as a multifunctional nanoplatform with their intrinsic physiochemical property and biological effect for satisfying the strict biomedical requirements. This comprehensive review focuses on recent progress of Mn‐based functional nanoplatforms in biomedicine with the particular discussion on their elaborate construction, physiochemical property, and theranostic applicability. Several Mn‐based nanosystems are discussed in detail, including solid/hollow MnOx nanoparticles, 2D MnOx nanosheets, MnOx‐silica/mesoporous silica nanoparticles, MnOx‐Fe3O4 nanoparticles, MnOx‐Au, MnOx‐fluorescent nanoparticles, Mn‐based organic composite nanosystem, and some specific/unique Mn‐based nanocomposites. Their versatile biomedical applications include pH/reducing‐responsive T1‐weighted positive magnetic resonance imaging, controlled drug loading/delivery/release, protection of neurological disorder, photothermal hyperthermia, photodynamic therapy, chemodynamic therapy, alleviation of tumor hypoxia, immunotherapy, and some specific synergistic therapies, which are based on their disintegration behavior under the mildly acidic/reducing condition, multiple enzyme‐mimicking activity, catalytic‐triggering Fenton reaction, etc. The biological effects and biocompatibility of these Mn‐based nanosystems are also discussed, accompanied with a discussion on challenges/critical issues and an outlook on the future developments and clinical‐translation potentials of these intriguing Mn‐based functional nanoplatforms.  相似文献   

2.
Monodisperse silica‐coated manganese oxide nanoparticles (NPs) with a diameter of ~35 nm are synthesized and are aminated through silanization. The amine‐functionalized core–shell NPs enable the covalent conjugation of a fluorescent dye, Rhodamine B isothiocyanate (RBITC), and folate (FA) onto their surface. The formed Mn3O4@SiO2(RBITC)–FA core–shell nanocomposites are water‐dispersible, stable, and biocompatible when the Mn concentration is below 50 µg mL?1 as confirmed by a cytotoxicity assay. Relaxivity measurements show that the core–shell NPs have a T1 relaxivity (r1) of 0.50 mM ?1 s?1 on the 0.5 T scanner and 0.47 mM ?1 s?1 on the 3.0 T scanner, suggesting the possibility of using the particles as a T1 contrast agent. Combined flow cytometry, confocal microscopy, and magnetic resonance imaging studies show that the Mn3O4@SiO2(RBITC)–FA nanocomposites can specifically target cancer cells overexpressing FA receptors (FARs). Findings from this study suggest that the silica‐coated Mn3O4 core–shell NPs could be used as a platform for bimodal imaging (both magnetic resonance and fluorescence) in various biological systems.  相似文献   

3.
Copper‐based ternary bimetal chalcogenides have very promising potential as multifunctional theragnosis nanoplatform for photothermal treatment of tumors. However, the design and synthesis of such an effective platform remains challenging. In this study, hydrophilic CuCo2S4 nanocrystals (NCs) with a desirable size of ≈10 nm are synthesized by a simple one‐pot hydrothermal route. The as‐prepared ultrasmall CuCo2S4 NCs show: 1) intense near‐infrared absorption, which is attributed to 3d electronic transitions from the valence band to an intermediate band, as identified by density functional theory calculations; 2) high photothermal performance with a photothermal conversion efficiency up to 73.4%; and 3) capability for magnetic resonance (MR) imaging, as a result of the unpaired 3d electrons of cobalt. Finally, it is demonstrated that the CuCo2S4 NCs are a promising “all‐in‐one” photothermal theragnosis nanoplatform for photothermal cancer therapy under the irradiation of a 915 nm laser at a safe power density of 0.5 W cm?2, guided by MR and infrared thermal imaging. This work further promotes the potential applications of ternary bimetal chalcogenides for photothermal theragnosis therapy.  相似文献   

4.
Magnetic‐fluid‐loadedliposomes (MFLs) of optimized magnetic responsiveness are newly worked out from the entrapment of superparamagnetic maghemite nanocrystals in submicronic PEG‐ylated rhodamine‐labelled phospholipid vesicles. This nanoplatform provides an efficient tool for the selective magnetic targeting of malignant tumors localized in brain and non‐invasive traceability by MRI through intravascular administration. As assessed by in vivo 7‐T MRI and ex vivo electron spin resonance, 4‐h exposure to 190‐T m–1 magnetic field gradient efficiently concentrates MFLs into human U87 glioblastoma implanted in the striatum of mice. The magnetoliposomes are then longer retained therein as checked by MRI monitoring over a 24‐h period. Histological analysis by confocal fluorescence microscopy confirms the significantly boosted accumulation of MFLs in the malignant tissue up to the intracellular level. Electron transmission microscopy reveals effective internalization by endothelial and glioblastoma cells of the magnetically conveyed MFLs as preserved vesicle structures. The magnetic field gradient emphasizes MFL distribution solely in the tumors according to the enhanced permeability and retention (EPR) effect while comparatively very low amounts are recovered in the other cerebral areas. Such a selective targeting precisely traceable by MRI is promising for therapeutic applications since the healthy brain tissue can be expected to be spared during treatments by deleterious anticancer drugs carried by magnetically guided MFLs.  相似文献   

5.
Biomimetic solid solutions of manganese and cobalt carbonates (MnCO3–CoCO3) are used as the precursors for the synthesis of the corresponding metal oxides. The different structures of the metal oxides with porous morphologies, such as pure manganese monoxide (MnO), the solid solution of manganese and cobalt monoxide (MnO–CoO), and the nanocomposite of MnO and metallic cobalt (MnO/Co), are obtained by the appropriate thermal treatments under a reduction atmosphere. The contents of cobalt species can be controlled by the initial cobalt concentration in the MnCO3–CoCO3 precursors. The resultant MnO/Co nanocomposites show the enhanced charge–discharge cycle stability and rate performance as an anode material of lithium‐ion battery.  相似文献   

6.
7.
Unpredictable in vivo therapeutic feedback of reactive oxygen species (ROS) efficiency is the major bottleneck of photodynamic therapy (PDT). Herein, novel PDT-based nanotheranostics Pa–Mn&CH-A@P are elaborately constructed for in vivo tracking biodistribution and in situ self-reporting PDT, which innovatively unites magnetic resonance imaging (MRI) and chemiluminescence (CL) signals. Taking advantages of the versatility of lanthanide coordination chemistry and flash nanoprecipitation (FNP) technology, photosensitizers, MRI, and CL agents are unprecedently integrated within a stable and uniform nanotheranostic. Specifically, MRI signal offers detailed dose distribution of nanotheranostics with high-spatial resolution, and CL signal timely performs in situ evaluation of ROS generation with high sensitivity. This dual-modal MRI/CL nanotheranostic makes a breakthrough in high fidelity feedback for oral tumor, conquering the inherent unpredictable obstacles on spatially and sensitively reporting PDT.  相似文献   

8.
Polypyrrole nanoparticles conjugating gadolinium chelates were successfully fabricated for dual‐modal magnetic resonance imaging (MRI) and photoacoustic imaging guided photothermal therapy of cancer, from a mixture of pyrrole and pyrrole‐1‐propanoic acid through a facile one‐step aqueous dispersion polymerization, followed by covalent attachment of gadolinium chelate, using polyethylene glycol as a linker. The obtained PEGylated poly­pyrrole nanoparticles conjugating gadolinium chelates (Gd‐PEG‐PPy NPs), sized around around 70 nm, exhibited a high T1 relaxivity coefficient of 10.61 L mm ?1 s?1, more than twice as high as that of the relating free Gd3+ complex (4.2 L mm –1 s?1). After 24 h intravenous injection of Gd‐PEG‐PPy NPs, the tumor sites exhibited obvious enhancement in both T1‐weighted MRI intensity and photoacoustic signal compared with that before injection, indicating the efficient accumulation of Gd‐PEG‐PPy NPs due to the introduction of the PEG layer onto the particle surface. In addition, tumor growth could be effectively inhibited after treatment with Gd‐PEG‐PPy NPs in combination with near‐infrared laser irradiation. The passive targeting and high MRI/photo­acoustic contrast capability of Gd‐PEG‐PPy NPs are quite favorable for precise cancer diagnosing and locating the tumor site to guide the external laser irradiation for photothermal ablation of tumors without damaging the surrounding healthy tissues. Therefore, Gd‐PEG‐PPy NPs may assist in better monitoring the therapeutic process, and contribute to developing more effective “personalized medicine,” showing great potential for cancer diagnosis and therapy.  相似文献   

9.
Monitoring of in vivo drug release from nanotheranostics by noninvasive approaches remains very challenging. Herein, novel redox‐responsive polymeric magnetosomes (PolyMags) with tunable magnetic resonance imaging (MRI) properties are reported for in vivo drug release monitoring and effective dual‐modal cancer therapy. The encapsulation of doxorubicin (DOX) significantly decreases PolyMags' T2‐contrast enhancement and transverse relaxation rate R2, depending on the drug loading level. The T2 enhancement and R2 can be recovered once the drug is released upon PolyMags' disassembly. T2‐ and T2*‐MRI and diffusion‐weighted imaging (DWI) are utilized to quantitatively study the correlation between MRI signal changes and drug release, and discover the MR tuning mechanisms. The in vivo drug release pattern is visualized based on such tunable MRI capability via monitoring the changes in T2‐weighted images, T2 and T2* maps, and R2 and R2* values. Interestingly, the PolyMags possess excellent photothermal effect, which can be further enhanced upon DOX loading. The PolyMags are highly efficacious to treat breast tumors on xenograft model with tumor‐targeted photothermal‐ and chemotherapy, achieving a complete cure rate of 66.7%. The concept reported here is generally applicable to other micellar and liposomal systems for image‐guided drug delivery and release applications toward precision cancer therapy.  相似文献   

10.
Manganese oxide nanocrystals are combined with aluminum oxide nanocrystals to improve their crystallinity via calcination without a significant increase of crystal size. A nanocomposite, consisting of two metal oxides, can be synthesized by the reaction between permanganate anions and aluminum oxyhydroxide keggin cations. The as‐prepared manganese oxide–aluminum oxide nanocomposite is X‐ray amorphous whereas heat‐treatment gives rise to the crystallization of an α‐MnO2 phase at 600 °C and Mn3O4/Mn2O3 and γ‐Al2O3 phases at 800 °C. Electron microscopy and N2 adsorption‐desorption‐isotherm analysis clearly demonstrate that the as‐prepared nanocomposite is composed of a porous assembly of monodisperse primary particles with a size of ~20 nm and a surface area of >410 m2 g?1. Of particular interest is that the small particle size of the as‐prepared nanocomposite is well‐maintained up to 600 °C, a result of the prevention of the growth of manganate grains through nanoscale mixing with alumina grains. The calcined nanocomposite shows very‐high catalytic activity for the oxidation of cyclohexene with an extremely high conversion efficiency of >95% within 15 min. The present results show that the improvement of the crystallinity without significant crystal growth is very crucial for optimizing the catalytic activity of manganese oxide nanocrystals.  相似文献   

11.
Imaging‐guided photothermal therapy based on functional nanomaterials has recently received significant attention and the selection of functional materials with optimal imaging and therapy effect is extremely important. In this work, NaDyF4‐based nanoparticles with varying size are synthesized by doping with different amounts of lutetium ions. To obtain an optimized material, the influence factor of magnetic resonance, X‐ray attenuation, and photothermal properties are discussed in detail. Then, NaDyF4:50%Lu@Prussian blue (PB) nanocomposite is selected as the optimal functional material for T1‐ and T2‐weighted magnetic resonance imaging, X‐ray computed tomography, and photothermal imaging‐guided photothermal therapy of tumor on a small animal model, and the treatment is applied with good results. Studies also suggest that the NaDyF4:50%Lu@PB nanocomposites are biocompatibile. The selection of an optimal material from a multi‐perspective study has provided an incentive for the development of an assortment of novel multifunctional materials for early cancer multifunctional diagnosis and imaging‐guided photothermal therapy.  相似文献   

12.
Despite the promise of ferrotherapy in cancer treatment, current ferrous therapeutics suffer from compromised antitumor ferroptosis efficacy and low specificity for tumors. Herein, a protease-activatable nanozyme (Fe3O4@Cu1.77Se) is reported for photoacoustic and tumor-enhanced magnetic resonance imaging (MRI)-guided second near-IR photothermal ferroptosis cancer therapy. Fe3O4@Cu1.77Se remains stable in physiological conditions, but disintegrates to increase reactive intratumoral ferrous supply for elevated hydroxyl radical generation by Fenton reaction and GSH depletion in response to overexpressed matrix metalloproteinases in tumor microenvironment, leading to amplified ferroptosis of tumor cells as well as enhanced T2-weighted MRI contrast. Further integration with second near-IR photoirradiation to generate localized heat not only triggers effective photothermal therapy and photoacoustic imaging but more importantly, potentiates Fenton reaction to promote ferroptotic tumor cell death. Such synergism leads to the polarization of tumor-associated macrophage from the tumor-promoting M2 type to the tumor-killing M1 type, and induces the immunogenic cells death of tumor cells, which in turn promotes the maturation of dendritic cells and infiltration of cytotoxic T lymphocytes in tumor, contributing to significant tumor suppression. This study presents a novel activatable ferrous nanotheranostics for spatial-temporal control over antitumor ferroptosis responses.  相似文献   

13.
The oxygen concentration dependence of sonodynamic therapy (SDT) and bioreductive therapy can be utilized to design the strategy of synergistic therapy. Herein, holmium‐doped hollow silica nanospheres are synthesized and then sequentially modified with chlorin e6, carboxyl poly(ethylene glycol) silane, and prostate stem cell antigen (PSCA) monoclonal antibody. The resultant nanocomposite designated as HHSN‐C/P‐mAb has good biocompatibility and can specifically target cancer cells overexpressing PSCA. Due to the inner cavity structure and Ho doping, HHSN‐C/P‐mAb shows high ultrasound (US) imaging contrast capability and excellent high‐field magnetic resonance contrast performance. HHSN‐C/P‐mAb can act as a nanocarrier for loading the bioreductive pro‐drug tirapazamine (TPZ), and the degradation of the hollow nanospheres under the trigger of acidic microenvironment favors the pH responsive release of TPZ from the material. Upon US irradiation, HHSN‐C/P‐mAb produces reactive oxygen species to kill the cancer cells, and importantly, the oxygen consumption during SDT induces an intratumoral hypoxic environment to activate the therapeutic function of codelivered TPZ, resulting in a high‐effective synergistic therapy. The findings of this study highlight that HHSN‐C/P‐mAb is a versatile theranostic nanoplatform for efficient cancer treatment.  相似文献   

14.
The ability to produce nanotherapeutics at large‐scale with high drug loading efficiency, high drug loading capacity, high stability, and high potency is critical for clinical translation. However, many nanoparticle‐based therapeutics under investigation suffer from complicated synthesis, poor reproducibility, low stability, and high cost. In this work, a simple method for preparing multifunctional nanoparticles is utilized that act as both a contrast agent for magnetic resonance imaging and a photosensitizer for photodynamic therapy for the treatment of cancer. In particular, the photosensitizer protoporphyrin IX (PpIX) is used to solubilize small nanoclusters of superparamagnetic iron oxide nanoparticles (SPIONs) without the use of any additional carrier materials. These nanoclusters are characterized with a high PpIX loading efficiency; a high loading capacity, stable behavior; high potency; and a synthetic approach that is amenable to large‐scale production. In vivo studies of photodynamic therapy (PDT) efficacy show that the PpIX‐coated SPION nanoclusters lead to a significant reduction in the growth rate of tumors in a syngeneic murine tumor model compared to both free PpIX and PpIX‐loaded poly(ethylene glycol)‐polycaprolactone micelles, even when injected at 1/8th the dose. These results suggest that the nanoclusters developed in this work can be a promising nanotherapeutic for clinical translation.  相似文献   

15.
基于MEMS深刻蚀技术和微电镀工艺,介绍了一种用于核磁共振成像(MRI)系统的微型射频(RF)接收线圈的设计与微加工制作方法,研制出了线圈内径为100μm,线圈厚度200μm,线圈宽度30μm,深宽比大于6,品质因数为4的微型金属螺旋线圈。实验结果表明,该制作工艺可为高深宽比的金属微结构的研制和核磁共振成像系统微型化提供新的方法和支持。  相似文献   

16.
Lead halide perovskite nanocrystals (PeNCs) are promising materials for applications in optoelectronics. However, their environmental instability remains to be addressed to enable their advancement into industry. Here the development of a novel synthesis method is reported for monodispersed PeNCs coated with all inorganic shell of cesium lead bromide (CsPbBr3) grown epitaxially on the surface of formamidinium lead bromide (FAPbBr3) NCs. The formed FAPbBr3/CsPbBr3 NCs have photoluminescence in the visible range 460–560 nm with narrow emission linewidth (20 nm) and high optical quantum yield, photoluminescence quantum yield (PLQY) up to 93%. The core/shell perovskites have enhanced optical stability under ambient conditions (70 d) and under ultraviolet radiation (50 h). The enhanced properties are attributed to overgrowth of FAPbBr3 with all‐inorganic CsPbBr3 shell, which acts as a protective layer and enables effective passivation of the surface defects. The use of these green‐emitting core/shell FAPbBr3/CsPbBr3 NCs is demonstrated in light‐emitting diodes (LEDs) and significant enhancement of their performance is achieved compared to core only FAPbBr3‐LEDs. The maximum current efficiency observed in core/shell NC LED is 19.75 cd A‐1 and the external quantum efficiency of 8.1%, which are approximately four times and approximately eight times higher, respectively, compared to core‐only devices.  相似文献   

17.
Nanoscale metal‐organic frameworks (NMOFs) have attracted increasing attention for biomedical applications due to their large specific surface area, good biocompatibility, adjustable structures, and diverse functions. By choosing appropriate metal ions and ligands, NMOFs can be synthesized and regulated to assist the diagnosis and treatment of cancer, acting as imaging agents, drug carriers, and cancer therapeutic agents. This review summarizes the recent advances of NMOFs in synthesis, biocompatibility, imaging, and applications in cancer therapies. Among these, the term “biocompatibility” is used to outline their various biological characteristics, and it is mainly discussed from the aspects of size and surface properties of NMOFs. The imaging section mainly emphasizes the application advantages of NMOFs as imaging agents in magnetic resonance, computed tomography, and fluorescence imaging. The applications of NMOFs in four cancer therapies, including phototherapy, radiotherapy, microwave therapy, and ultrasonic therapy, are addressed, especially for thermal and dynamic therapy. Finally, the prospects and challenges of NMOFs in imaging and cancer therapies are also discussed.  相似文献   

18.
Multimodal imaging, which combines complementary information of two or more imaging modalities, offers huge advantages. In this paper, the synthesis, characterization, and application of superparamagnetic nitrogen‐doped carbon‐iron oxide hybrid quantum dots (C‐Fe3O4 QDs) is reported for triple‐modal bioimaging through fluorescence/magnetic resonance/computed tomography (FL/MR/CT). Especially, C‐Fe3O4 QDs are synthesized by using poly (γ‐glutamic acid) as a precursor and stabilizer via a green and facile one‐pot hydrothermal approach. The as‐prepared C‐Fe3O4 QDs exhibit excellent water dispersibility, wavelength‐tunable FL property with high quantum yield of about 21.6%, good photostability, strong superparamagnetic property as well as favorable biocompatibility. Meanwhile, these C‐Fe3O4 QDs also show a transverse relaxivity value (r 2) of 154.10 mm ?1 s?1 for T2‐weighted MR imaging mode and an observable X‐ray attenuation effect for CT imaging mode. Moreover, the in vivo bioimaging of tumor‐bearing nude mice by combining FL, MR, and CT images further demonstrates that the as‐prepared C‐Fe3O4 QDs can be readily and efficiently used in FL/MR/CT triple‐modal tumor imaging. Hence, the new and facile one‐pot synthesis strategy for preparing multifunctional C‐Fe3O4 QDs nanoprobes provides a convenient way for achieving an effective and versatile agent for tumorous bioimaging/or diagnostics.  相似文献   

19.
An implantable anticancer device (IAD) amenable to eradicate local regional recurrence (LRR) of breast cancer as well as to enhance the breast reconstruction during/after therapy is proposed for the first time. The IAD is fabricated by incorporating the superparamagnetic graphene oxide doxorubicin nanocomposite of size ≈200 nm in a nanofiber matrix to enable the sustained and tumor specific anticancer drug release over 60 d in vitro with a minimum initial burst release and the repeated hyperthermic capability in an alternating magnetic field to ensure the synergistic inhibition of LRR. The IAD also enriches the reconstruction of poor breast cosmesis that resulted from the surgical treatment by supporting the lipofilling of the surgical residual cavity to induce the adipogenic process. Moreover, the noninvasive monitoring capability of IAD through magnetic resonance imaging augments to the effective patient care. Thus, this work reports a new and reliable concept by introducing the multifunctional IAD possessing enhanced specificity with a real‐time monitoring capability and long‐term anticancer efficacy as a potential platform for synergistic inhibition of LRR and a great promise for the in situ breast reconstruction ability for better breast cosmesis.  相似文献   

20.
Cell membrane–based nanosystems with desirable characteristics have been studied extensively for many therapeutic applications. However, current research has focused on single cell membrane, and multifunctional fused membrane materials from different membrane types are still rare. Herein, a platelet–cancer stem cell (CSC) hybrid membrane‐coated iron oxide magnetic nanoparticle (MN) {[CSC‐P]MN} is presented for the first time for the enhanced photothermal therapy of head and neck squamous cell carcinoma (HNSCC). Inherited from the original source cells, the platelet membrane shows immune evading ability due to the surface marker comprising a number of “don't eat me” signals, and the CSC membrane has homotypic targeting capabilities due to the specific surface adhesion molecules. The [CSC‐P]MNs possess superior characteristics for immune evasion, active cancer targeting, magnetic resonance imaging, and photothermal therapy. Compared with single cell membrane–coated MNs, [CSC‐P]MNs exhibit prolonged circulation times and enhanced targeting abilities. Moreover, the [CSC‐P]MNs exhibit a superior photothermal ability that provides excellent HNSCC tumor growth inhibition, particularly in an immunocompetent Tgfbr1/Pten conditional double knockout HNSCC mouse model that contains a more complex tumor microenvironment that is similar to the human HNSCC microenvironment. Collectively, this biomimetic multimembrane‐coated nanoplatform may provide enhanced antitumor efficacy in the complex tumor microenvironment.  相似文献   

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