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1.
Abstract

Carbon fluoroxide (CFO) nanoparticles (NPs) produced from silicon carbide wafers are used as both fluorescent probes and sonosensitizers for theranostic application. In vitro cell tests were carried out to investigate the feasibility of ultrasound-based therapy with the use of the CFO NPs. The NPs that penetrated inside the cells were shown to provoke cell destruction after application of an ultrasound treatment. No significant toxic effect was observed when the cells were treated with NP concentrations up to 0.5 mg ml?1 without applying ultrasound treatment. The obtained results open a new way toward cancer therapy strategies.  相似文献   

2.
Multifunctional probes for simultaneous magnetic resonance imaging (MRI) and drug delivery have attracted considerable interest due to their promising potential applications in the early-stage diagnosis and therapy of the diseases. In this study, hollow manganese phosphate nanoparticles (HMP NPs) with an average diameter of 18 nm were synthesized and aminated through silanization, which enabled the covalent conjugation of biocompatible poly(ethylene glycol) (PEG) on their surfaces. The anti-tumor drug doxorubicin (DOX) could be loaded into the hollow cavities. Under physiological conditions (pH 7.4), the NPs showed low MRI T 1 contrast (r 1 = 1.19 L·mmol?1·s?1), whereas high T 1 enhancement (r 1 = 5.22 L·mmol?1·s?1) was achieved after dissolving them in endosome/lysosome mimetic conditions (pH 5.4). This is due to the fact that the NPs were easily eroded, which resulted in the release of Mn2+ at low pH. To use this interesting phenomenon for targeted DOX drug delivery, we conjugated the tumor-targeting ligand folic acid (FA) on HMP NPs and investigated their drug delivery capacity and cytotoxicity to cell lines expressing different amount of folate receptor (FR). KB cells showed more significant cellular uptake than HeLa cells and A549 cells, as confirmed by confocal laser scanning microscopy (CLSM), flow cytometry and cellular T 1-weighted MRI. Furthermore, the drug-loaded HMP NPs exhibited greater cytotoxicity to KB cells. Our results suggest that functionalized HMP NPs can act as an effective multifunctional probe for selective diagnosis with MRI, as well as giving efficient targeted drug delivery.   相似文献   

3.
Spinel-structured Ni-Zn ferrite nanoparticles (NPs) have been directly synthesized by a low temperature co-precipitation method. The structure and high-frequency magnetic properties of the particles were investigated. The as-prepared Ni-Zn ferrite NPs demonstrate typical soft magnetic properties. The saturation magnetization (Ms), as high as about 60 emu/g, was achieved. The imaginary part μ' ' of the permeability shows a broad peak in the frequency range 200 MHz~6 GHz, which indicates that the as-prepared Ni-Zn ferrite NPs have a remarkable feature of electromagnetic (EM) wave absorption in the high-frequency range. Hence, resultant Ni-Zn ferrite NPs can be used as efficient microwave absorbers and effective heating mediators for hyperthermia application in cancer therapy.  相似文献   

4.
Three composite modes of CoFe2 O 4/BaTiO3 (CFO/BTO) were created with appropriate stoichiometric proportion. They are nitrate solution of CFO mixed with BTO (SCB), self-propagating precursor of CFO mixed with BTO (PCB), and the made-up CFO mixed with BTO (MCB) separately. The microstructural, ferroelectric, and ferromagnetic properties of SCB, PCB, and MCB bulk composites were investigated. SCB, PCB, and MCB bulk composites with a molar ratio of 2:8 were calcined at 1020, 1120, and 1160 °C, respectively. And X-ray diffraction (XRD) analysis showed that they all correspond to the CFO with cubic spinel structure and the BTO with tetragonal perovskite structure. The formation temperature of BTO with hexagonal structure is related to the distance of inter-diffusion and Co 2+ concentration in the CFO/BTO bulk composite. The wet chemical routing is of benefit to inhibit the agglomeration of the BTO in the CFO/BTO bulk composite. The maximum polarization of 5.24 μC/cm 2 was received in the MCB bulk composite sintered at 1160 °C with a molar ratio of 1:9. The maximum saturation magnetization of 31.609 emu/g and the remnant magnetization of 10.336 emu/g were obtained in the MCB bulk composite sintered at 1160 °C with a molar ratio of 4:6. The threshold ferromagnetic phase content of percolation which has an effect on the MCB bulk composite is less than 40 mol %.  相似文献   

5.
We have developed a processing technique for producing cobalt ferrite (CFO)/lead lanthanum zirconate titanate (PLZT) 0-3 composites with enhanced piezoelectric, ferroelectric and magnetoelectrical (ME) coupling properties. It includes modifying the phase boundary with zirconia barrier layer and decreasing the sintering temperature with Li2O + 0.5Bi2O3 additives. The CFO/PLZT 0-3 composites were successfully fabricated via conventional co-firing procedures. The obtained 0-3 composite ceramics can withstand a DC electric field of 6 kV mm−1. The effects of CFO/PLZT ratio on the crystalline structure, piezoelectric, ferroelectric, dielectric and M–E properties were investigated. The ME coefficients of the composites with CFO:PLZT volume ratio of 14.4:85.6, 27.4:72.6 and 39.3:60.7 were found to be 31, 52 and 143 mV (Oe cm)−1 at 100 kHz under a bias field of ∼1 kOe.  相似文献   

6.
Purpose: Metformin hydrochloride (MF) repurposing as adjuvant anticancer therapy for colorectal cancer (CRC) proved effective. Several studies attempted to develop MF-loaded nanoparticles (NPs), however the entrapment efficiency (EE%) was poor. Thus, the present study aimed at the facile development of a new series of chitosan (CS)-based semi-interpenetrating network (semi-IPN) NPs incorporating Pluronic® nanomicelles as nanocarriers for enhanced entrapment and sustained release of MF for efficient treatment of CRC.

Methods: The NPs were prepared by ionic gelation and subsequently characterized using FTIR, DSC, TEM, and DLS. A full factorial design was also adopted to study the effect of various formulation variables on EE%, particle size, and zeta-potential of NPs.

Results: NPs had a spherical shape and a mean particle size ranging between 135 and 220?nm. FTIR and DSC studies results were indicative of successful ionic gelation with the drug being dispersed in its amorphous form within CS-Pluronic® matrix. Maximum EE% reaching 57.00?±?12.90% was achieved using Pluronic®-123 based NPs. NPs exhibited a sustained release profile over 48?h. The MF-loaded NPs sensitized RKO CRC cells relative to drug alone.

Conclusion: The reported results highlighted the novel utility of the developed NPs in the arena of colon cancer treatment.  相似文献   

7.
Glioblastoma multiforme (GBM) is a very common type of “incurable” malignant brain tumor. Although many treatment options are currently available, most of them eventually fail due to its recurrence. Boron neutron capture therapy (BNCT) emerges as an alternative noninvasive therapeutic treatment modality. The major challenge in treating GBMs using BNCT is to achieve selective imaging, targeting, and sufficient accumulation of boron‐containing drug at the tumor site so that effective destruction of tumor cells can be achieved without harming the normal brain cells. To tackle this challenge, this study demonstrates for the first time that an unprecedented 10B‐enriched (96% 10B enrichment) boron nanoparticle nanomedicine (10BSGRF NPs) surface‐modified with a Fluorescein isothiocyanate (FITC)‐labeled RGD‐K peptide can pass through the brain blood barrier, selectively target at GBM brain tumor sites, and deliver high therapeutic dosage (50.5 µg 10B g?1 cells) of boron atoms to tumor cells with a good tumor‐to‐blood boron ratio of 2.8. The 10BSGRF NPs not only can enhance the contrast of magnetic resonance (MR) imaging to help diagnose the location/size/progress of brain tumor, but also effectively suppress murine brain tumors via MR imaging‐guided BNCT, prolonging the half‐life of mice from 22 d (untreated group) to 39 d.  相似文献   

8.
Vector plays an important role in hepatic targeted drug delivery system. In this study, a novel material as a liver targeting vector, dual-ligand modified chitosan (GCGA) composed of chitosan (CTS), glycyrrhetinic acid (GA) and lactobionic acid (LA), was designed and synthesized by an orthogonal experiment with two-step synthesis under mild conditions. The synthesized final product was characterized and confirmed by FTIR and 1H-NMR spectroscopy, and DS of GA and LA in CTS were measured to be 13.77 and 16.74 mol% using 1H-NMR, respectively. The cytotoxicity of CTS and GCGA was concentration dependent which was inverse proportion to the cell viability by MTT assay using L929 cell line, and inhibitory concentration 50% (IC50) was 0.2 mg/ml for GCGA. The in vitro targeting efficiency and the in vitro cellular uptake were investigated. Compared with CTS NPs and GA-CTS NPs, GCGA NPs showed good cell specificity to BEL-7402 cells via the dual-ligand-receptor-mediated recognition, leading to a higher affinity to BEL-7402 cells. The results suggested that GCGA described here has the potential to be used as an effective vector for hepatic targeted drug therapy.  相似文献   

9.
《Advanced Powder Technology》2020,31(9):3686-3694
It is of great significance to examine the adverse effects of nanoparticles (NPs) on the environments and human health. In the present study, we have investigated the toxicological effects of NPs on two distinct strains of yeast, S. cerevisiae and S. pombe, in aqueous solutions of NaCl. The positively charged NPs of 100-nm diameter were more significantly adhered on (and uptaken by) a negatively charged cell of every yeast strain at lower ionic strength. Every yeast in 150-mM NaCl solution (high ionic strength) showed the cell viability of more than 80% even after exposure to 100-μg/mL NPs, whereas in 5-mM NaCl solution (low ionic strength) it exhibited zero cell viability at 25-μg/mL NPs. Interestingly, the dead cells in 5-mM NaCl solution containing 6.25–12.5 μg/mL NPs exhibited about 2-fold amount of cellular adhesion/uptake of NPs, compared with the corresponding live cells. The ratio between the saturated amounts of the cellular adhesion/uptake of NPs in 5-mM and 150-mM NaCl solutions for S. cerevisiae was about eighteen times greater than that for S. pombe. This behavior of S. cerevisiae is explained in part by the larger ratio between the zeta potentials of a cell in 5-mM and 150-mM NaCl solutions.  相似文献   

10.
Piezoelectric material-mediated sonodynamic therapy (SDT) has received considerable research interest in cancer therapy. However, the simple applications of conventional piezoelectric materials do not realize the full potential of piezoelectric materials in medicine. Therefore, the energy band structure of a piezoelectric material is modulated in this study to meet the actual requirement for cancer treatment. Herein, an elaborate PEGylated piezoelectric solid solution 0.7BiFeO3-0.3BaTiO3 nanoparticles (P-BF-BT NPs) is synthesized, and the resultant particles achieve excellent piezoelectric properties and their band structure is tuned via band engineering. The tuned band structure of P-BF-BT NPs is energetically favorable for the synchronous production of superoxide radicals (•O2) and oxygen (O2) self-supply via water splitting by the piezoelectric effect. Besides, the P-BF-BT NPs can initiate the Fenton reaction to generate hydroxyl radical (•OH), and thus, chemodynamic therapy (CDT) can be augmented by ultrasound. Detailed in vitro and in vivo research has verified the promising effects of multimodal imaging-guided P-BF-BT NP-mediated synergistic SDT/CDT by the piezo-Fenton process in hypoxic tumor elimination, accompanied by high therapeutic biosafety. The current demonstrates a novel strategy for designing and synthesizing “custom-made” piezoelectric materials for cancer therapy in the future.  相似文献   

11.
This paper describes the effect of low concentrations of 100 nm polyethylene glycol-modified TiO2 nanoparticles (TiO2-PEG NPs) on HepG2 hepatocellular carcinoma cells. Proliferation of HepG2 cells increased significantly when the cells were exposed to low doses (<100 μg ml–1) of TiO2-PEG NPs. These results were further confirmed by cell counting experiments and cell cycle assays. Cellular uptake assays were performed to determine why HepG2 cells proliferate with low-dose exposure to TiO2-PEG NPs. The results showed that exposure to lower doses of NPs led to less cellular uptake, which in turn decreased cytotoxicity. We therefore hypothesized that TiO2-PEG NPs could affect the activity of hepatocyte growth factor receptors (HGFRs), which bind to hepatocyte growth factor and stimulate cell proliferation. The localization of HGFRs on the surface of the cell membrane was detected via immunofluorescence staining and confocal microscopy. The results showed that HGFRs aggregate after exposure to TiO2-PEG NPs. In conclusion, our results indicate that TiO2-PEG NPs have the potential to promote proliferation of HepG2 cells through HGFR aggregation and suggest that NPs not only exhibit cytotoxicity but also affect cellular responses.  相似文献   

12.
Nanoparticles (NPs) elicit various physiological responses in cellular environment, and the effect of NPs on cell migration is of high interest. In this work, the effects of NPs on cell migration and their possible mechanisms were studied. Here, we showed that after exposure to pegylated titanium dioxide nanoparticles (TiO2-PEG NPs, where PEG stands for the polyethylene glycol), NCI-H292 cells exhibited slower migration than control cells. Furthermore, larger NPs inhibited cell migration much stronger than smaller NPs. Following NP exposure, the cells showed decreased expression of integrin beta 1 and phosphorylated focal adhesion kinase (pFAK), and disrupted F-actin structures. We demonstrated that a possible mechanism involved NP-mediated promotion of the lysosomal degradation of integrin beta 1, thus leading to reduced expression of pFAK and cytoskeletal disruption and inhibited cell migration. Therefore, our results showed that inhibition of NCI-H292 cell migration by NPs is mediated through integrin beta 1, which provides useful information for the application of NPs in cancer therapy and related fields.  相似文献   

13.
Conjugated polymers (CPs) with strong near‐infrared (NIR) absorption and high heat conversion efficiency have emerged as a new generation of photothermal therapy (PTT) agents for cancer therapy. An efficient strategy to design NIR absorbing CPs with good water dispersibility is essential to achieve excellent therapeutic effect. In this work, poly[9,9‐bis(4‐(2‐ethylhexyl)phenyl)fluorene‐alt‐co‐6,7‐bis(4‐(hexyloxy)phenyl)‐4,9‐di(thiophen‐2‐yl)‐thiadiazoloquinoxaline] (PFTTQ) is synthesized through the combination of donor–acceptor moieties by Suzuki polymerization. PFTTQ nanoparticles (NPs) are fabricated through a precipitation approach using 1,2‐distearoyl‐ sn ‐glycero‐3‐phosphoethanolamine‐N‐[methoxy(polyethylene glycol)‐2000] (DSPE‐PEG2000) as the encapsulation matrix. Due to the large NIR absorption coefficient (3.6 L g‐1 cm‐1), the temperature of PFTTQ NP suspension (0.5 mg/mL) could be rapidly increased to more than 50 °C upon continuous 808 nm laser irradiation (0.75 W/cm2) for 5 min. The PFTTQ NPs show good biocompatibility to both MDA‐MB‐231 cells and Hela cells at 400 μg/mL of NPs, while upon laser irradiation, effective cancer cell killing is observed at a NP concentration of 50 μg/mL. Moreover, PFTTQ NPs could efficiently ablate tumor in in vivo study using a Hela tumor mouse model. Considering the large amount of NIR absorbing CPs available, the general encapsulation strategy will enable the development of more efficient PTT agents for cancer or tumor therapy.  相似文献   

14.
Photodynamic therapy (PDT) combining with near infrared (NIR) imaging is attractive. However, the intrinsic hypoxia in tumor and consumption of oxygen during treatment will decrease PDT. Here an artificial red cell was prepared using polypeptides conjugated hemoglobin as an oxygen carrier. A NIR photosensitizer-brominated 4,4-difluoro-4-bora-3a,a-diaza-s-indacene (BODIPY-Br2) possessing both high fluorescence emission and singlet oxygen generation efficiency was synthesized and also conjugated to polypeptides to achieve NIR imaging-guided PDT. In vitro studies performed on HepG2 cancer cells verified the oxygen carrier, cancer tracing and curing abilities of the as-prepared polymeric nanoparticles. Even under hypoxia condition, it also obviously increases the cell killing rate when exposed light at a low energy (25 mW/cm2, 10 min). Meanwhile, the fluorescence of BODIPY in NPs would light up cells for real-time imaging. These results show the potential of the biocompatible and biodegradable P-Hb-B NPs for enhancement of simultaneous tracing and treating of cancer.  相似文献   

15.
Sunscreens containing ZnO and TiO2 nanoparticles (NPs) are increasingly applied to skin over long time periods to reduce the risk of skin cancer. However, long‐term toxicological studies of NPs are very sparse. The in vitro toxicity of ZnO and TiO2 NPs on keratinocytes over short‐ and long‐term applications is reported. The effects studied are intracellular formation of radicals, alterations in cell morphology, mitochondrial activity, and cell‐cycle distribution. Cellular response depends on the type of NP, concentration, and exposure time. ZnO NPs have more pronounced adverse effects on keratinocytes than TiO2. TiO2 has no effect on cell viability up to 100 μg mL?1, whereas ZnO reduces viability above 15 μg mL?1 after short‐term exposure. Prolonged exposure to ZnO NPs at 10 μg mL?1 results in decreased mitochondrial activity, loss of normal cell morphology, and disturbances in cell‐cycle distribution. From this point of view TiO2 has no harmful effect. More nanotubular intercellular structures are observed in keratinocytes exposed to either type of NP than in untreated cells. This observation may indicate cellular transformation from normal to tumor cells due to NP treatment. Transmission electron microscopy images show NPs in vesicles within the cell cytoplasm, particularly in early and late endosomes and amphisomes. Contrary to insoluble TiO2, partially soluble ZnO stimulates generation of reactive oxygen species to swamp the cell redox defense system thus initiating the death processes, seen also in cell‐cycle distribution and fluorescence imaging. Long‐term exposure to NPs has adverse effects on human keratinocytes in vitro, which indicates a potential health risk.  相似文献   

16.
In this study, horseradish peroxidase/nickel oxides nanoparticles/glassy carbon (HRP/NiO NPs/GC) electrode was prepared by first applying nickel oxides nanoparticles on glassy carbon surface and then horseradish peroxidase immobilized on the NiO NPs. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) have been used as a diagnostic tools to identify the synthesized NiO NPs. Immobilized HRP showed an electrochemical redox behavior pertained to HRP(Fe(III)–Fe(II)) by direct electron transfer between protein and nanoparticles with a formal potential (E0′) of ? 55.5 mV (vs. Ag/AgCl and 141.5 mV vs. NHE) in 50 mM phosphate buffer solution (PBS). The anodic charge transfer coefficient (α) and heterogeneous electron transfer rate constant (ks) were 0.42 and 0.75 s? 1, respectively. Biocatalytic activity of HRP/NiO NPs/GC electrode for reduction of hydrogen peroxide and application to hydrogen peroxide determination was exemplified.  相似文献   

17.
Phototherapy is a promising treatment method for cancer therapy. However, the various factors have greatly restricted phototherapy development, including the poor accumulation of photosensitizer in tumor, hypoxia in solid tumor tissue and systemic phototoxicity. Herein, a mitochondrial‐targeted multifunctional dye‐anchored manganese oxide nanoparticle (IR808@MnO NP) is developed for enhancing phototherapy of cancer. In this nanoplatform, IR808 as a small molecule dye acts as a tumor targeting ligand to make IR808@MnO NPs with capacity to actively target tumor cells and relocate finally in the mitochondria. Meanwhile, continuous production of oxygen (O2) and regulation of pH induced by the high reactivity and specificity of MnO NPs toward mitochondrial endogenous hydrogen peroxide (H2O2) could effectively modulate tumor hypoxia and lessen the tumor subacid environment. Large amounts of reactive oxide species (ROS) are generated during the reaction process between H2O2 and MnO NPs. Furthermore, under laser irradiation, IR808 in IR808@MnO NPs turns O2 into a highly toxic singlet oxygen (1O2) and generates hyperthermia. The results indicate that IR808@MnO NPs have the high efficiency of specific targeting of tumors, relieving tumor subacid environment, improving the tumor hypoxia environment, and generating large amounts of ROS to kill tumor cells. It is expected to have a wide application in treating cancer.  相似文献   

18.
The development of new and simple green chemical methods for synthesizing colloidal solutions of functional nanoparticles is desirable for environment-friendly applications. In the present work, we report a feasible method for synthesizing colloidal solutions of silver nanoparticles (Ag NPs) based on the modified Tollens technique. The Ag NPs were stabilized by using oleic acid as a surfactant and were produced for the first time by the reduction of silver ammonium complex [Ag(NH3)2]+(aq) by glucose with UV irradiation treatment. A stable and nearly monodisperse aqueous Ag NPs solution with average-sized particles (~ 9–10 nm) was obtained. The Ag NPs exhibited high antibacterial activity against both Gram-negative Escherichia Coli (E. coli) and Gram-positive Staphylococcus aureus bacteria. Electron microscopic images and analyses provided further insights into the interaction and bactericidal mechanism of the Ag NPs. The proposed method of synthesis is an effective way to produce highly bactericidal colloidal solutions for medical, microbiological, and industrial applications.  相似文献   

19.
Different research methods were used to study the microstructural and magnetoelectric properties of multiferroic Sr3CuNb2O9–CoFe2O4 (SCNO–CFO). X-ray verification provides fundamental information about the local symmetry of the two-phase SCNO–CFO ceramic. P4mm unit cell with minimal tetragonality and a cubic Fd-3m structure have been found for SCNO and CFO, respectively. Some additional traces of cupric oxide were also detected. SEM observations confirmed that the microstructure is built of various crystallites forming a two-component electroceramics and CuO-rich grain boundary segregation. Impedance spectroscopy studies reveal the thermally activated dielectric relaxations. The temperature-dependent behavior of the diffuse dielectric anomalies was successfully described by the modified Debye equation. Finally, magnetoelectric measurements clearly confirm intrinsic coupling between the piezoelectric and magnetic phases of SCNO–CFO.  相似文献   

20.
The emergence of multidrug resistant bacteria has resulted in plenty of stubborn nosocomial infections and severely threatens human health. Developing novel bactericide and therapeutic strategy is urgently needed. Herein, mesoporous silica supported silver–bismuth nanoparticles (Ag‐Bi@SiO2 NPs) are constructed for synergistic antibacterial therapy. In vitro experiments indicate that the hyperthermia originating from Bi NPs can disrupt cell integrity and accelerate the Ag ions release, further exhibiting an excellent antibacterial performance toward methicillin‐resistant Staphylococcus aureus (MRSA). Besides, under laser irradiation, Ag‐Bi@SiO2 NPs at 100 µg mL?1 can effectively obliterate mature MRSA biofilm and cause a 69.5% decrease in the biomass, showing a better therapeutic effect than Bi@SiO2 NPs with laser (26.8%) or Ag‐Bi@SiO2 NPs without laser treatment (30.8%) groups. More importantly, in vivo results confirm that ≈95.4% of bacteria in abscess are killed and the abscess ablation is accelerated using the Ag‐Bi@SiO2 NPs antibacterial platform. Therefore, Ag‐Bi@SiO2 NPs with photothermal‐enhanced antibacterial activity are a potential nano‐antibacterial agent for the treatment of skin infections.  相似文献   

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