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Antiangiogenesis-Combined Photothermal Therapy in the Second Near-Infrared Window at Laser Powers Below the Skin Tolerance Threshold
摘要： Photothermal agents with strong light absorption in the second near-infrared (NIR-II) region (1000–1350 nm) are strongly desired for successful photothermal therapy (PTT). In this work, titania-coated Au nanobipyramids (NBP@TiO2) with a strong plasmon resonance in the NIR-II window were synthesized. The NBP@TiO2 nanostructures have a high photothermal conversion efficiency of (93.3 ± 5.2)% under 1064-nm laser irradiation. They are also capable for loading an anticancer drug combretastatin A-4 phosphate (CA4P). In vitro PTT studies reveal that 1064-nm laser irradiation can efficiently ablate human lung cancer A549 cells and enhance the anticancer effect of CA4P. Moreover, the CA4P-loaded NBP@TiO2 nanostructures combined with PTT induce a synergistic antiangiogenesis effect. In vivo studies show that such CA4P-loaded NBP@TiO2 nanostructures under mild 1064-nm laser irradiation at an optical power density of 0.4 W cm?2, which is lower than the skin tolerance threshold value, exhibit a superior antitumor effect. This work presents not only the development of the NBP@TiO2 nanostructures as a novel photothermal agent responsive in the NIR-II window but also a unique combined chemo-photothermal therapy strategy for cancer therapy.
关键词： Antiangiogenesis therapy,Gold nanobipyramids,Plasmon resonance,Core@shell nanostructures,Photothermal therapy
更新于2025-11-21 11:24:58
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Fabrication of gold-silver core-shell nanoparticles for performing as ultrabright SERS-nanotags inside human ovarian cancer cells
摘要： This paper presents the fabrication and characterization of new gold-silver core-shell nanoparticles labeled with para-mercaptobenzoic acid (4MBA) molecules and demonstrates their use as SERS-nanotags with ultra-bright traceability inside cells and ability to convey spectrally-coded information about the intracellular pH by means of Surface-Enhanced Raman Spectroscopy (SERS). Unlike to previous reported studies, our fabrication procedure includes in the first step the synthesis of chitosan-coated gold nanoparticles as a seed material with subsequent growing of a silver shell. The bimetallic core-shell structure is revealed by transmission electron microscopy (TEM), high-angle annular dark field scanning transmission electron microscopy (HAADF-STEM), energy-dispersive X-ray elemental mapping (EDX) and the presence of two interacting localized surface plasmon resonance (LSPR) modes in UV-Vis extinction spectrum. The high SERS activity and sensitivity of as fabricated 4MBA-chit-Au-AgNPs nano-constructs to different pH in solution is investigated under 532 and 633 nm laser lines excitation. Next, in view of future studies in cancer diagnosis, the in vitro antiproliferative effects of SERS-nanotags against human ovarian adenocarcinoma cells (NIH:OVCAR-3) are evaluated. The capacity to operate as bright SERS nanotags with precise localization at a single cell level as well as intracellular pH indicators is clearly demonstrated by performing cell imaging under scanning confocal Raman microscopy.
关键词： core-shell nanoparticles,pH sensors,ovarian cancer cells,chitosan,SERS tags
更新于2025-11-21 11:24:58
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Enhanced surface plasmon resonance (SPR) signals based on immobilization of core-shell nanoparticles incorporated boron nitride nanosheets: Development of molecularly imprinted SPR nanosensor for anticancer drug, etoposide
摘要： An effective SPR nanosensor based on core-shell nanoparticles (Ag@AuNPs) incorporated hexagonal boron nitride (HBN) nanosheets and molecularly imprinted polymer (MIP) was presented for etoposide (ETO) detection. Scanning electron microscope (SEM), transmission electron microscope (TEM), x-ray diffraction (XRD) method, cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), fourier transform infrared (FTIR) spectroscopy and atomic force microscopy (AFM) methods were utilized for all characterizations of nanomaterials and polymer surfaces. ETO imprinted SPR nanosensor based on Ag@AuNPs-HBN nanocomposite was developed in the presence of poly(2-hydroxyethyl methacrylate-methacryloylamidoglutamic acid) [p(HEMA-MAGA)]. The results of the study have revealed that 0.001 - 1.00 ng mL-1 (1.70×10-12 - 1.70×10-9 M) and 0.00025 ng mL-1 (4.25×10-13 M) were found as the linearity range and the detection limit (LOD). Furthermore, the prepared SPR nanosensor was examined in terms of stability, repeatability and selectivity. Finally, the imprinted SPR nanosensor was applied to the urine samples having high recovery.
关键词： Etoposide,Core-shell nanoparticles,Hexagonal boron nitride,Urine sample,Molecular imprinted nanosensor
更新于2025-11-21 11:18:25
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Nanoparticles for Bioapplications: Study of the Cytotoxicity of Water Dispersible CdSe(S) and CdSe(S)/ZnO Quantum Dots
摘要： Semiconductor nanocrystals or quantum dots (QDs) have unique optical and physical properties that make them potential imaging tools in biological and medical applications. However, concerns over the aqueous dispersivity, toxicity to cells, and stability in biological environments may limit the use of QDs in such applications. Here, we report an investigation into the cytotoxicity of aqueous dispersed CdSe(S) and CdSe(S)/ZnO core/shell QDs in the presence of human colorectal carcinoma cells (HCT-116) and a human skin fibroblast cell line (WS1). The cytotoxicity of the precursor solutions used in the synthesis of the CdSe(S) QDs was also determined in the presence of HCT-116 cells. CdSe(S) QDs were found to have a low toxicity at concentrations up to 100 μg/mL, with a decreased cell viability at higher concentrations, indicating a highly dose-dependent response. Meanwhile, CdSe(S)/ZnO core/shell QDs exhibited lower toxicity than uncoated QDs at higher concentrations. Confocal microscopy images of HCT-116 cells after incubation with CdSe(S) and CdSe(S)/ZnO QDs showed that the cells were stable in aqueous concentrations of 100 μg of QDs per mL, with no sign of cell necrosis, confirming the cytotoxicity data.
关键词： core/shell QDs,HCT-116,water dispersive QDs,WS1,bioapplications of QDs,aqueous synthesis,in vitro cytotoxicity of QDs
更新于2025-11-21 11:08:12
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Core-shell metal-organic frameworks with fluorescence switch to trigger an enhanced photodynamic therapy
摘要： The design of hybrid metal-organic framework (MOF) nanomaterials by integrating inorganic nanoparticle into MOF (NP@MOF) has demonstrated outstanding potential for obtaining enhanced, collective, and extended novel physiochemical properties. However, the reverse structure of MOF-integrated inorganic nanoparticle (MOF@NP) with multifunction has rarely been reported. Methods: We developed a facile in-situ growth method to integrate MOF nanoparticle into inorganic nanomaterial and designed a fluorescence switch to trigger enhanced photodynamic therapy. The influence of “switch” on the photodynamic activity was studied in vitro. The in vivo mice with tumor model was applied to evaluate the “switch”-triggered enhanced photodynamic therapy efficacy. Results: A core-satellites structure with fluorescence off and on function was obtained when growing MnO2 on the surface of fluorescent zeolitic imidazolate framework (ZIF-8) nanoparticles. Furthermore, A core-shell structure with photodynamic activity off and on function was achieved by growing MnO2 on the surface of porphyrinic ZrMOF nanoparticles (ZrMOF@MnO2). Both the fluorescence and photodynamic activities can be turned off by MnO2 and turned on by GSH. The GSH-responsive activation of photodynamic activity of ZrMOF@MnO2 significantly depleted the intracellular GSH via a MnO2 reduction reaction, thus triggering an enhanced photodynamic therapy efficacy. Finally, the GSH-reduced Mn2+ provided a platform for magnetic resonance imaging-guided tumor therapy. Conclusion: This work highlights the impact of inorganic nanomaterial on the MOF properties and provides insight to the rational design of multifunctional MOF-inorganic nanomaterial complexes.
关键词： Core-shell structure,Metal-organic frameworks,Fluorescence switch,Photodynamic therapy
更新于2025-11-21 11:08:12
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Highly flexible self-powered photodetectors based on core–shell Sb/CdS nanowires
摘要： Flexible photodetectors have great applications in flexible image sensors, wearable electronics and smart robots. In this work, we reported the fabrication of highly flexible self-powered photodetectors with core-shell Sb/CdS nanowires as the sensing materials. The fabricated device exhibited high Ion/Ioff ratio of 3.54×103 under zero bias, fast speed of photoresponse and great stability. An open-circuit voltage of 0.35 V was generated due to the presence of CdS and CdSb interfaces within the core-shell nanowires. Besides, the photocurrent of the flexible device is nearly invariable at various bending angles and even after thousands of bending cycles, demonstrating the excellent flexibility and bending stability. The results indicated that the self-powered photodetectors are promising candidates for future passive optoelectronic devices.
关键词： core-shell Sb/CdS nanowires,optoelectronic devices,self-powered,flexible photodetectors
更新于2025-11-21 11:03:13
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Highly sensitive and selective label-free detection of dopamine in human serum based on nitrogen-doped graphene quantum dots decorated on Au nanoparticles: Mechanistic insights through microscopic and spectroscopic studies
摘要： A rapid, facile and label-free sensing strategy is developed for the detection of dopamine (DA) in the real samples by exploiting nitrogen-doped graphene quantum dots (N-GQDs) decorated on Au nanoparticles (Au@N-GQD). The as-grown Au@N-GQD exhibits strong blue fluorescence at room temperature and the fluorescence intensity is drastically quenched in presence of DA in neutral medium. The mechanistic insight into the DA sensing by Au@N-GQDs is explored here by careful monitoring of the evolution of the interaction of Au NPs and N-GQDs with DA under different conditions through electron microscopic and spectroscopic studies. The highly sensitive and selective detection of DA over a wide range is attributed to the unique core-shell structure formation with Au@N-GQD hybrids. The quenching mechanism involves the ground state complex formation as well as electron transfer from N-GQDs. The presence of Au NPs in Au@N-GQD hybrids accelerates the quenching process (~14 fold higher than bare N-GQDs) by the formation of stable dopamine-o-quinone (DQ) in this present detection scheme. The fluorescence quenching follows the linear Stern-Volmer plot in the range 0-100 μM, establishing its efficacy as a fluorescence-based DA sensor with a limit of detection (LOD) 590 nM, which is ~27 fold lower than the lowest abnormal concentration of DA in serum (16 μM). This sensing scheme is also successively applied to trace DA in Brahmaputra river water sample with LOD 480 nM including its satisfactory recovery (95-112%). Our studies reveal a novel sensing pathway for DA through the core-shell structure formation and it is highly promising for the design of efficient biological and environmental sensor.
关键词： Dopamine,Fluorescence quenching,Nitrogen-doped graphene quantum dots,Colorimetric sensing,Core-shell structure,Gold nanoparticles
更新于2025-11-21 11:01:37
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Dual-mode luminescent core-shell nanoarchitectures for highly sensitive optical nanothermometry
摘要： Currently, FIR-based luminescent nanothermometry has aroused wide concern for its promising applications in fast-moving objects, harsh environments and microscopic temperature. Synchronously promoting the absolute and relative sensitivities of optical thermometers is one of the significant issues at present. In this work, a new nanothermometry strategy to possess both high absolute and relative sensitivities have been proposed by coupling of thermally-coupled-levels-based technique with non-thermally-coupled-levels method in the core-shell designed nanomaterials. Following this strategy, the core-shell-structured NaGdF4:Yb,Er@ NaYF4:Ce,Tb,Eu nanocrystals have been successfully prepared. Remarkably, the adverse cross-relaxation among different activators is extremely suppressed owing to the spatial separation of Er3+ and Eu3+/Tb3+ activators, being conducive to the realization of both intense green upconverting emissions and yellow downshifting luminescence. Moreover, the temperature-sensitive dual-mode luminescent behaviors of core-shell nanomaterials are systematically studied to probe the possible application in FIR-related luminescent thermometry. Specially, the thermally-coupled-levels-based FIR of Er3+ : 2H11/2 / 4I15/2 to Er3+ : 4S3/2 / 4I15/2 and non-thermally-coupled-levels-based FIR of Eu3+ : 5D0 / 7F2 to Tb3+ : 5D4 / 7F6 are proved to be applicable as temperature probes, leading to the achievement of dual-mode temperature sensing. Using the pre-designed core@shell nanoarchitectures, the absolute sensitivity can reach up to 1.02% K-1 based on Eu3+/Tb3+ Stokes emissions and the relative sensitivity could reach as high as 1.12% K-1 based on Er3+ anti-Stokes luminescence. We believe that this study provides a valid approach for developing high-performance optical nanothermometers.
关键词： Optical nanothermometry,Rare-earth luminescent materials,Dual-mode emission,Core-shell nanoarchitectures
更新于2025-11-20 15:33:11
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Au@Cu Core-Shell Nanocubes with Controllable Sizes in the Range of 20-30 nm for Applications in Catalysis and Plasmonics
摘要： Predominantly covered by a single type of {100} facets, Cu nanocubes are attractive catalytic material toward reactions such as electrochemical reduction of CO2. Here we report a seed-mediated approach to the facile synthesis of Au@Cu core-shell nanocubes with hexadecylamine and Cl- serving as capping agents toward the {100} facets of Cu and glucose as a reducing agent. The large (12%) lattice mismatch between Cu and Au led to the localized epitaxial growth of Cu shells on the Au seeds and the formation of nanocubes with randomly distributed Au cores. Compared to the same synthesis in the absence of Au seeds, the reduction of Cu(II) ions was greatly accelerated in the presence of Au seeds because of the autocatalytic surface reduction. It was also found that the structure and morphology of the products were highly dependent on the concentration of Cu(II) precursor in the reaction solution. Nanoplates rather than nanocubes were obtained when the concentration of Cu(II) precursor was reduced down to a certain level. By varying the reaction time and/or the amount of Au seeds, the size of the Au@Cu nanocubes could be tuned in a range of 20–30 nm. The as-synthesized core-shell nanocubes exhibited a strong localized surface plasmon resonance peak at 581 nm and the resonance was dominated by absorption rather than scattering. It is expected that the Au@Cu nanocubes with uniform and controllable sizes will find use in a variety of applications such as plasmonics and catalysis.
关键词： lattice mismatch,Copper nanocubes,core-shell nanocrystals,plasmonics,seed-mediated growth
更新于2025-11-19 16:56:35
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A facile synthesis of palladium encased Ag nanowires and its effect on fluorescence and catalysis
摘要： A facile polyol synthetic route was designed to prepare an ultra thin Pd nano sheath over Ag nanowires (NWs) forming metal-metal core–shell nanocomposites. Here we report the one pot synthesis of Pd assembly onto growing Ag NWs. Pd salts were reduced over varied time intervals during the growth process of the Ag NWs. The Pd salt was introduced after 20, 30- and 40-minutes to the growing Ag NWs. The product was designated as Ag@Pd 20, 30, and 40 on basis of introducing interval. The morphology and constituents of each product was observed using SEM coupled with EDX. XRD was employed to characterize composite material. UV-Visible was used to determine the SPR of each material along with the pure Ag NWs and palladium nanoparticles. Similarly, ?uorescence of each product was characterized using PL spectrophotometer, which was correlated with core and sheath. Finally, the catalytic reduction of nitrophenol into amino phenol by ultra thin sheet of Pd of each product was investigated and reaction order was ascertained.
关键词： core@shell,?uoroscence,catalytic reduction,Pd-Ag composites
更新于2025-11-19 16:46:39