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基于金刚石量子传感的纳米磁成像及凝聚态物理应用 被引量:3
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作者 丁哲 石发展 杜江峰 《物理》 CAS 北大核心 2020年第6期359-372,共14页
作为凝聚态物理的重要方向,磁性的研究不仅是发展自旋电子学器件的基础,也是突破已有材料和器件功能壁垒的关键之一。磁性材料的纳米分辨率成像对认识和理解物质微观性质至关重要。金刚石中的氮-空位(NV)色心是一种对磁信号敏感的原子缺... 作为凝聚态物理的重要方向,磁性的研究不仅是发展自旋电子学器件的基础,也是突破已有材料和器件功能壁垒的关键之一。磁性材料的纳米分辨率成像对认识和理解物质微观性质至关重要。金刚石中的氮-空位(NV)色心是一种对磁信号敏感的原子缺陷,经过十余年的深入研究,其已经发展为兼具高灵敏度和高空间分辨率的磁量子传感器,能够以纳米分辨率对单层磁性材料进行成像。它作为一种广谱(DC-GHz)、高灵敏度(nT/Hz^1/2)、高空间分辨率(~10 nm,理论极限~1 nm)的磁成像技术,可以对包括二维磁性材料、电流分布、电导率分布乃至单个电子自旋,少数个核自旋进行纳米磁成像。文章从NV色心微观结构和性质出发,介绍其作为量子传感进行磁信号探测和成像的原理;进一步从技术层面介绍谱仪的构成和探针制备;最后选取有代表性的工作,简要介绍NV扫描显微镜在各方面的应用。 展开更多
关键词 量子传感 氮-空穴色心 金刚石 纳米磁成像
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磁纳米粒子成像中非线性磁化信号二次谐波检测方法研究 被引量:2
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作者 武明 杜强 +1 位作者 柯丽 祖婉妮 《电子测量与仪器学报》 CSCD 北大核心 2022年第9期87-94,共8页
磁纳米粒子成像(magnetic particle imaging, MPI)中粒子信号的检测精度直接影响图像分辨率。针对MPI中磁纳米粒子信号强微弱、检测难的实际问题,提出一种基于二次谐波的磁纳米粒子非线性磁化信号检测方法。该方法采用交流磁场与直流偏... 磁纳米粒子成像(magnetic particle imaging, MPI)中粒子信号的检测精度直接影响图像分辨率。针对MPI中磁纳米粒子信号强微弱、检测难的实际问题,提出一种基于二次谐波的磁纳米粒子非线性磁化信号检测方法。该方法采用交流磁场与直流偏置场耦合场作为激励磁场,增强磁纳米粒子检测信号能量。结合双平面梯度检测线圈,检测粒子信号的二次谐波信号,去除背景信号的干扰。通过仿真与检测实验证明基于二次谐波的磁纳米粒子信号检测方法的有效性。并对粒子实测数据处理结果表明,在交流激励场强和直流偏置场强的比值最优时,该方法获得粒子信号的信噪比是原有三次谐波检测方法的1.52倍,有效增强了粒子检测信号的信噪比。本文为MPI系统提供了一种更高精度的信号检测方法。 展开更多
关键词 纳米粒子成像 耦合场 直流偏 二次谐波 信号检测
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纳米磁颗粒电磁探测及成像技术研究进展
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作者 朱健健 杨文晖 +2 位作者 魏树峰 王铮 吕行 《中国生物医学工程学报》 CAS CSCD 北大核心 2018年第3期344-352,共9页
近10年来,磁纳米颗粒已由最初的核磁共振造影剂发展成为集疾病诊断、靶向药物输送及磁热疗等一体化诊断平台的功能性材料。磁纳米颗粒成像(MPI)是一种通过检测注射到血管中的超顺磁性纳米颗粒的磁性来构建三维图像的计算机断层成像技术... 近10年来,磁纳米颗粒已由最初的核磁共振造影剂发展成为集疾病诊断、靶向药物输送及磁热疗等一体化诊断平台的功能性材料。磁纳米颗粒成像(MPI)是一种通过检测注射到血管中的超顺磁性纳米颗粒的磁性来构建三维图像的计算机断层成像技术。除血管造影和干细胞跟踪,磁纳米颗粒成像在生物医学上有一系列令人激动的潜在的应用,例如实时透视、诊断和分期癌症、体内炎症成像、温度显示和功能性分子成像等。该技术试图在现有的造影剂成像技术上以更敏感、更快捷、更安全的方式得到确定体积内的示踪剂分布的图像。首先介绍磁纳米颗粒在分子成像与诊疗应用研究进展,进一步说明磁纳米颗粒的电磁探测的原理,重点从扫描仪线圈拓扑结构和图像重建两方面介绍磁颗粒的电磁成像技术的研究现状和存在的问题,最后提出未来技术重要的发展趋势。 展开更多
关键词 分子成像 诊疗 探测 纳米颗粒成像技术
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Tumor Molecular Imaging with Nanoparticles 被引量:3
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作者 Zhen Cheng Xuefeng Ya +2 位作者 Xilin Sun BaozhongShen Sanjiv Sam Gambhir 《Engineering》 SCIE EI 2016年第1期132-140,共9页
Molecular imaging(MI)can provide not only structural images using traditional imaging techniques but also functional and molecular information using many newly emerging imaging techniques.Over the past decade,the util... Molecular imaging(MI)can provide not only structural images using traditional imaging techniques but also functional and molecular information using many newly emerging imaging techniques.Over the past decade,the utilization of nanotechnology in MI has exhibited many significant advantages and provided new opportunities for the imaging of living subjects.It is expected that multimodality nanoparticles(NPs)can lead to precise assessment of tumor biology and the tumor microenvironment.This review addresses topics related to engineered NPs and summarizes the recent applications of these nanoconstructs in cancer optical imaging,ultrasound,photoacoustic imaging,magnetic resonance imaging(MRI),and radionuclide imaging.Key challenges involved in the translation of NPs to the clinic are discussed. 展开更多
关键词 TUMOR Molecular imaging NANOPARTICLES
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Bimodal visualization of colorectal uptake of nanoparticles in dimethylhydrazine-treated mice 被引量:2
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作者 Tao Wu Wei-Liang Zheng +2 位作者 Shi-Zheng Zhang Ji-Hong Sun Hong Yuan 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第31期3614-3622,共9页
AIM:To investigate colorectal uptake of solid lipid nanoparticles(SLNs) in mice receiving different doses of 1,2-dimethylhydrazine(DMH) using magnetic resonance(MR) and laser-scanning confocal fluorescence microscope(... AIM:To investigate colorectal uptake of solid lipid nanoparticles(SLNs) in mice receiving different doses of 1,2-dimethylhydrazine(DMH) using magnetic resonance(MR) and laser-scanning confocal fluorescence microscope(LSCFM) imaging.METHODS:Eight mice were sacrificed in a pilot study to establish the experimental protocol and to visualize colorectal uptake of SLNs in normal mice.Gadopentetate dimeglumine and fluorescein isothiocyanate(FITC)-loaded SLN(Gd-FITC-SLN) enemas were performed on mice receiving DMH for 10 wk(group 1,n = 9) or 16 wk(group 2,n = 7) and FITC-SLN enema wasperformed on 4 DMH-treated mice(group 3).Pre-and post-enema MR examinations were made to visualize the air-inflated distal colorectum.Histological and LSCFM examinations were performed to verify colorectal malignancy and to track the distribution of SLNs.RESULTS:Homogeneous enhancement and dense fluorescence(FITC) deposition in colorectal wall were observed in normal mice and 1 DMH-treated mouse(group 1) on fluid attenuated inversion recovery(FLAIR) and LSCFM images,respectively.Heterogeneous mural enhancement was found in 6 mice(4 in group 1;2 in group 2).No visible mural enhancement was observed in the other mice.LSCFM imaging revealed linear fluorescence deposition along the colorectal mucosa in all groups.Nine intraluminal masses and one prolapsed mass were detected by MR imaging with different enhancement modes and pathologies.Interstitial FITC deposition was identified where obvious enhancement was observed in FLAIR images.Bladder imaging agent accumulations were observed in 11 of 16 DMH-treated mice of groups 1 and 2.CONCLUSION:There are significant differences in colorectal uptake and distribution of SLNs between normal and DMH-treated mice,which may provide a new mechanism of contrast for MR colonography. 展开更多
关键词 Solid lipid nanoparticles Colorectal cancer Magnetic resonance colonography
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Recent advances in biological detection with magnetic nanoparticles as a useful tool 被引量:6
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作者 Liwei Lu Xiuyu Wang +1 位作者 Chuanxi Xiong Li Yao 《Science China Chemistry》 SCIE EI CAS CSCD 2015年第5期793-809,共17页
Magnetic nanoparticles have emerged as a powerful tool for magnetic resonance imaging, biodetection, drug delivery, and hyperthermia. This review focuses on the biological detection of magnetic nanoparticles as well a... Magnetic nanoparticles have emerged as a powerful tool for magnetic resonance imaging, biodetection, drug delivery, and hyperthermia. This review focuses on the biological detection of magnetic nanoparticles as well as their physicochemical properties. Substantial progress in the sensitivity of detection has been made by developing variety of methods. Five applications of magnetic nanoparticles in biological detection are discussed in this review: magnetic separation, magnetic sensing, magnetic manipulation, magnetic catalysis, and signal enhancer for surface plasmon resonance(SPR). Finally, some future trends and perspectives in these research areas are outlined. 展开更多
关键词 magnetic nanoparticles biological detection sensitivity METHODS
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The effect of neighbor distance of magnetic nanoparticle clusters on magnetic resonance relaxation properties 被引量:1
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作者 Dan Wang Bingbing Lin +4 位作者 Taipeng Shen Jun Wu Chunchao Xia Bin Song Hua Ai 《Science Bulletin》 SCIE EI CAS CSCD 2016年第13期1023-1030,共8页
Superparamagnetic iron oxide (SPIO) nanoparticle clusters are one unique form which can enhance magnetic relaxivity and improve the magnetic resonance imaging contrast at the same iron concentration, comparing to si... Superparamagnetic iron oxide (SPIO) nanoparticle clusters are one unique form which can enhance magnetic relaxivity and improve the magnetic resonance imaging contrast at the same iron concentration, comparing to single SPIO nanoparticles. Controlling of cluster size and other structural parameters have drawn great interests in this field to further improve their magnetic properties. In this study, we investigated how the interparticle distance (also known as neighbor distance) of SP10 nanocrystals within clusters affect their magnetic relaxation behaviors. To adjust the neighbor distance, different amount of cholesterol (CHO) was chosen as model spacers embedded into SPIO nanocluster systems with the help of amphiphilic diblock copolymer poly(ethylene glyco)-polyester. Small- angle X-ray scattering was applied to quantify the neighbor distance of SPIO clusters. The results demonstrated that the averaged SPIO nanocrystal neighbor distance of nan- oclusters increased with higher amount of added CHO. Moreover, these SPIO nanocrystal clusters had the promi- nent magnetic relaxation properties. Simultaneously, con- trolling of SPIO nanocrystal neighbor distance can regulate the saturation magnetization (Ms) and magnetic resonance (MR) T2 relaxation of the aggregation, and ultimately obtain better MR contrast effects with decreased neighbor distance. 展开更多
关键词 Iron oxide nanoparticle CLUSTERS Neighbor distance Magnetic properties T2relaxation
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Hollow iron oxide nanoparticles as multidrug resistant drug delivery and imaging vehicles 被引量:11
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作者 Ruijun Xing Ashwinkumar A. Bhirde +4 位作者 Shouju Wang Xiaolian Sun Gang Liu Yanglong Hou Xiaoyuan Chen 《Nano Research》 SCIE EI CAS CSCD 2013年第1期1-9,共9页
Magnetic nanopartides have been used as drug delivery vehicles against a number of cancer cells. Most of these theranostic formulations have used solid iron oxide nanoparticles (SIONPs) loaded with chemotherapeutics... Magnetic nanopartides have been used as drug delivery vehicles against a number of cancer cells. Most of these theranostic formulations have used solid iron oxide nanoparticles (SIONPs) loaded with chemotherapeutics as nano-carrier formulation for both magnetic resonance imaging (MRI) and cancer therapy. In this study, we applied the dopamine-plus-human serum albumin (HSA) method to modify hollow iron oxide nanoparticles (HIONPs) and encapsuated doxorubicin (DOX) within the hollow porous structure of the nano-carrier. The new delivery system can load more drug than solid iron oxide nanoparticles of the same core size using the same coating strategy. The HIONPs-DOX formulation also has a pH-dependent drug release behaviour. Compared with free DOX, the HIONPs-DOX were more effectively uptaken by the multidrug resistant OVCAR8- ADR cells and consequently more potent in killing drug resistant cancer cells. MRI phantom and cell studies also showed that the HIONPs-DOX can decrease the T2 MRI signal intensity and can be used as a MR/contrast agent while acting as a drug delivery vehicle. For the first time, the dual application of chemo drug transport and MR imaging using the HIONPs-DOX formulation was achieved against both DOX-sensitive and DOX-resistant cancer cells. 展开更多
关键词 drug resistance hollow nanoparticles DOXORUBICIN magnetic resonanceimaging (MRI) drug delivery
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On-demand degradable magnetic resonance imaging nanoprobes 被引量:2
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作者 Wenbo Sun Zonghua Wang +5 位作者 Jianhua Liu Chunhuan Jiang Weihua Chen Bin Yu Wei Wang Lehui Lu 《Science Bulletin》 SCIE EI CSCD 2021年第7期676-684,M0004,共10页
Theranostic nanoprobes can potentially integrate imaging and therapeutic capabilities into a single platform,offering a new personalized cancer diagnostic tool.However,there is a growing concern that their clinical ap... Theranostic nanoprobes can potentially integrate imaging and therapeutic capabilities into a single platform,offering a new personalized cancer diagnostic tool.However,there is a growing concern that their clinical application is not safe,particularly due to metal-containing elements,such as the gadolinium used in magnetic resonance imaging(MRI).We demonstrate for the first time that the photothermal melting of the DNA duplex helix was a reliable and versatile strategy that enables the on-demand degradation of the gadolinium-containing MRI reporter gene from polydopamine(PDA)-based theranostic nanoprobes.The combination of chemotherapy(doxorubicin)and photothermal therapy,which leads to the enhanced anti-tumor effect.In vivo MRI tracking reveals that renal filtration was able to rapidly clear the free gadolinium-containing MRI reporter from the mice body.This results in a decrease in the long-term toxic effect of theranostic MRI nanoprobes.Our findings may pave the way to address toxicity issues of the theranostic nanoprobes. 展开更多
关键词 MRI reporter DNA-based Photothermal melting On-demand degradation Theranostic nanoprobes
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