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1.
Opt Express ; 23(13): 17056-66, 2015 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-26191714

RESUMEN

We proposed and demonstrated a label-free imaging method for living cells using a GaInAsP H0-type photonic crystal nanolaser array. We integrated 441 nanolasers in an arrayed configuration and achieved photopumped lasing with a 100% yield. Then, we attached HeLa cells on it, measured the wavelengths of all nanolasers and used them as pixel information. We acquired cell images, which partially corresponds to optical micrographs and probably reflects the attachment condition of the cells. We improved the refractive index resolution from ~10(-2) to 2 × 10(-3) by incorporating a nanoslot into each nanolaser and compensating the nonuniformity of each index sensitivity.

2.
IEEE Trans Magn ; 51(2)2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26023242

RESUMEN

The magnetic response of magnetic particle imaging (MPI) tracers varies with the slew rate of the applied magnetic field, as well as with the tracer's average magnetic core size. Currently, 25 kHz and 20 mT/µ0 drive fields are common in MPI, but lower field amplitudes may be necessary for patient safety in future designs. We studied how several different sizes of monodisperse MPI tracers behaved under different drive field amplitude and frequency, using magnetic particle spectrometry and ac hysteresis for drive field conditions at 16, 26, and 40 kHz, with field amplitudes from 5 to 40 mT/µ0. We observed that both field amplitude and frequency can influence the tracer behavior, but that the magnetic behavior is consistent when the slew rate (the product of field amplitude and frequency) is consistent. However, smaller amplitudes provide a correspondingly smaller field of view, sometimes resulting in excitation of a minor hysteresis loop.

3.
Nanomedicine ; 10(6): 1165-74, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24709330

RESUMEN

Gene transfer technique has various applications, ranging from cellular biology to medical treatments for diseases. Although nonviral vectors, such as episomal vectors, have been developed, it is necessary to improve their gene transfer efficacy. Therefore, we attempted to develop a highly efficient gene delivery system combining an episomal vector with magnetic nanoparticles (MNPs). In comparison with the conventional method using transfection reagents, polyethylenimine-coated MNPs introduced episomal vectors more efficiently under a magnetic field and could express the gene in mammalian cells with higher efficiency and for longer periods. This novel in vitro separation method of gene-introduced cells utilizing the magnetic property of MNPs significantly facilitated the separation of cells of interest. Transplanted cells in vivo were detected using magnetic resonance. These results suggest that MNPs play multifunctional roles in ex vivo gene transfer, such as improvement of gene transfer efficacy, separation of cells, and detection of transplanted cells. FROM THE CLINICAL EDITOR: This study convincingly demonstrates enhanced efficiency of gene transfer via magnetic nanoparticles. The method also enables magnetic sorting of cells positive for the transferred gene, and in vivo monitoring of the process with MRI.


Asunto(s)
Separación Celular/métodos , Imagen por Resonancia Magnética/métodos , Nanopartículas de Magnetita/química , Plásmidos/administración & dosificación , Transfección/métodos , Animales , Células Cultivadas , Humanos , Nanopartículas de Magnetita/análisis , Polietileneimina/química
4.
Nanoscale Adv ; 5(17): 4354-4367, 2023 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-37638161

RESUMEN

Magnetic nanoparticles possess unique properties distinct from other types of nanoparticles developed for biomedical applications. Their unique magnetic properties and multifunctionalities are especially beneficial for central nervous system (CNS) disease therapy and diagnostics, as well as targeted and personalized applications using image-guided therapy and theranostics. This review discusses the recent development of magnetic nanoparticles for CNS applications, including Alzheimer's disease, Parkinson's disease, epilepsy, multiple sclerosis, and drug addiction. Machine learning (ML) methods are increasingly applied towards the processing, optimization and development of nanomaterials. By using data-driven approach, ML has the potential to bridge the gap between basic research and clinical research. We review ML approaches used within the various stages of nanomedicine development, from nanoparticle synthesis and characterization to performance prediction and disease diagnosis.

5.
J Nanotheranostics ; 3(1): 19-38, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37600442

RESUMEN

Breast cancer is one of the leading causes of death in the female population worldwide. Standard treatments such as chemotherapy show noticeable results. However, along with killing cancer cells, it causes systemic toxicity and apoptosis of the nearby healthy cells, therefore patients must endure side effects during the treatment process. Implantable drug delivery devices that enhance therapeutic efficacy by allowing localized therapy with programmed or controlled drug release can overcome the shortcomings of conventional treatments. An implantable device can be composed of biopolymer materials, nanocomposite materials, or a combination of both. This review summarizes the recent research and current state-of-the art in these types of implantable devices and gives perspective for future directions.

6.
ACS Sens ; 6(2): 340-347, 2021 02 26.
Artículo en Inglés | MEDLINE | ID: mdl-32449356

RESUMEN

Magneto-electric nanoparticles (MENPs), composed of a piezoelectric shell and a ferromagnetic core, exhibited enhanced cell uptake and controlled drug release due to the enhanced localized electric field (surface charge/potential) and the generation of acoustics, respectively, upon applying alternating current (AC) magnetic (B)-field stimulation. This research, for the first time, implements an electrochemical single-entity approach to probe AC B-field induced strain mediated surface potential enhancement on MENP surface. The surface potential changes at the single-NP level can be probed by the open circuit potential changes of the floating carbon nanoelectrode (CNE) during the MENP-CNE collision events. The results confirmed that the AC B-field (60 Oe) stimulation caused localized surface potential enhancement of MENP. This observation is associated with the presence of a piezoelectric shell, whereas magnetic nanoparticles were found unaffected under identical stimulation.


Asunto(s)
Nanopartículas , Electricidad , Campos Magnéticos , Magnetismo , Imanes
7.
Nanoscale ; 12(39): 20546, 2020 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-33016979

RESUMEN

Correction for 'Dynamic magnetic characterization and magnetic particle imaging enhancement of magnetic-gold core-shell nanoparticles' by Asahi Tomitaka et al., Nanoscale, 2019, 11, 6489-6496, DOI: 10.1039/C9NR00242A.

8.
Crit Rev Biomed Eng ; 48(3): 189-198, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33389896

RESUMEN

The human immunodeficiency virus (HIV) envelope glycoprotein protein 120 (gp120) induces neurotoxicity associated with HIV-associated neurocognitive disorders (HAND). Mechanism of Gp120-mediated neurotoxicity is primarily apoptosis. Currently, there are no therapeutics that address gp120 neurotoxicity. A biocompatible, efficacious therapeutic that easily crosses the blood-brain barrier (BBB) is needed to treat neuronal toxicity observed in HIV-infected individuals. Magnetic nanoparticles (MNPs) have successfully delivered anti-HIV agents across in vitro BBB transwell model. However, MNPs at high doses may damage cells. Exosomal extracellular vesicles (xEVs) are endogenous nanocarriers capable of crossing the BBB. Unlike MNPs, xEVs interact with cells in a paracrine or juxtracrine manner, lacking long-range site specificity. Here we investigated the efficacy of an MNP and xEV-coupled therapeutic (M-NEXT) as a nanocarrier for targeted delivery of anti-HIV fusion agent across the BBB to inhibit HIV-gp120 associated neuropathology. M-NEXT consisting of MNPs encapsulated within xEV carrying T20 peptide on the surface was synthesized and characterized via zeta potential, dynamic light scattering, and TEM imaging. Preliminary efficacy studies using SH-SY5Y cocultured with the in vitro BBB model showed that the M-NEXT-T20-fusion peptide protected neurons from HIV gp120-mediated neurotoxicity. Additionally, BBB integrity and permeability assessed via trans-endothelial resistance (TEER) and a Dextran-FITC transport assay was unaffected. SH-SY5Y viability measured by XTT assay was not significantly modulated by M-NEXT. In summary, preliminary findings support M-NEXT as effective nanocarriers for delivery of anti-HIV gp120 associated neurotoxicity agents.


Asunto(s)
Infecciones por VIH , VIH-1 , Nanopartículas de Magnetita , Infecciones por VIH/tratamiento farmacológico , Humanos , Neuronas
9.
Sci Rep ; 10(1): 10115, 2020 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-32572041

RESUMEN

Smart multifunctional nanoparticles with magnetic and plasmonic properties assembled on a single nanoplatform are promising for various biomedical applications. Owing to their expanding imaging and therapeutic capabilities in response to external stimuli, they have been explored for on-demand drug delivery, image-guided drug delivery, and simultaneous diagnostic and therapeutic (i.e. theranostic) applications. In this study, we engineered nanoparticles with unique morphology consisting of a superparamagnetic iron oxide core and star-shaped plasmonic shell with high-aspect-ratio gold branches. Strong magnetic and near-infrared (NIR)-responsive plasmonic properties of the engineered nanostars enabled multimodal quantitative imaging combining advantageous functions of magnetic resonance imaging (MRI), magnetic particle imaging (MPI), photoacoustic imaging (PAI), and image-guided drug delivery with a tunable drug release capacity. The model drug molecules bound to the core-shell nanostars were released upon NIR illumination due to the heat generation from the core-shell nanostars. Moreover, our simulation analysis showed that the specific design of the core-shell nanostars demonstrated a pronounced multipolar plasmon resonance, which has not been observed in previous reports. The multimodal imaging and NIR-triggered drug release capabilities of the proposed nanoplatform verify their potential for precise and controllable drug release with different applications in personalized medicine.


Asunto(s)
Sistemas de Liberación de Medicamentos/métodos , Nanopartículas de Magnetita/química , Nanopartículas Multifuncionales/química , Animales , Liberación de Fármacos/fisiología , Fenómenos Electromagnéticos , Compuestos Férricos/química , Oro , Humanos , Imagen por Resonancia Magnética , Magnetismo , Nanopartículas Multifuncionales/uso terapéutico , Imagen Multimodal , Fototerapia/métodos , Medicina de Precisión/métodos
10.
Artículo en Inglés | MEDLINE | ID: mdl-32426338

RESUMEN

The emerging field of theranostics for advanced healthcare has raised the demand for effective and safe delivery systems consisting of therapeutics and diagnostics agents in a single monarchy. This requires the development of multi-functional bio-polymeric systems for efficient image-guided therapeutics. This study reports the development of size-controlled (micro-to-nano) auto-fluorescent biopolymeric hydrogel particles of chitosan and hydroxyethyl cellulose (HEC) synthesized using water-in-oil emulsion polymerization technique. Sustainable resource linseed oil-based polyol is introduced as an element of hydrophobicity with an aim to facilitate their ability to traverse the blood-brain barrier (BBB). These nanogels are demonstrated to have salient features such as biocompatibility, stability, high cellular uptake by a variety of host cells, and ability to transmigrate across an in vitro BBB model. Interestingly, these unique nanogel particles exhibited auto-fluorescence at a wide range of wavelengths 450-780 nm on excitation at 405 nm whereas excitation at 710 nm gives emission at 810 nm. In conclusion, this study proposes the developed bio-polymeric fluorescent micro- and nano- gels as a potential theranostic tool for central nervous system (CNS) drug delivery and image-guided therapy.

11.
Crit Rev Biomed Eng ; 47(6): 489-494, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-32421973

RESUMEN

Magnetic nanoparticles have been studied extensively for biomedical applications over the past decades. One of the promising applications of magnetic nanoparticles is hyperthermia, which refers to thermal treatment for cancer. To achieve adequate heat at target sites, it is essential to develop magnetic nanoparticles with high heating efficiency and to optimize external magnetic fields. Here, we discuss the heating mechanism of magnetic nanoparticles, the influence of the intracellular environment on magnetic behavior and heat generation, and recent advances in methods of heating efficiency assessment.


Asunto(s)
Hipertermia Inducida , Espacio Intracelular , Nanopartículas de Magnetita/química , Línea Celular Tumoral , Membrana Celular/química , Membrana Celular/metabolismo , Humanos , Espacio Intracelular/química , Espacio Intracelular/metabolismo , Fenómenos Físicos
12.
Crit Rev Biomed Eng ; 47(6): 495-505, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-32421974

RESUMEN

Liposomes, one of the most promising drug delivery carriers, have been extensively studied for the treatment of various diseases and have made their way to the market. Magnetic nanoparticles have been attracting great interest for diagnostic and therapeutic applications due to their unique magnetic properties. An integration of liposomes and magnetic nanoparticles gives great potential to the field of smart drug delivery systems, including magnetically guided drug delivery, image-guided drug delivery, and externally triggered controlled drug release using hyperthermia or alternating magnetic fields. In this review, we discuss the recent development of magnetoliposomes for controlled-release drug delivery systems and their potential.


Asunto(s)
Preparaciones de Acción Retardada , Liposomas , Nanopartículas de Magnetita , Células HeLa , Humanos
13.
Nanoscale ; 11(13): 6489-6496, 2019 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-30892348

RESUMEN

Multifunctional nanoparticles with a magnetic core and gold shell structures are emerging multi-modal imaging probes for disease diagnosis, image-guided therapy, and theranostic applications. Owing to their multi-functional magnetic and plasmonic properties, these nanoparticles can be used as contrast agents in multiple complementary imaging modalities. Magnetic particle imaging (MPI) is a new pre-clinical imaging system that enables real-time imaging with high sensitivity and spatial resolution by detecting the dynamic responses of nanoparticle tracers. In this study, we evaluated the dynamic magnetic properties and MPI imaging performances of core-shell nanoparticles with a magnetic core coated with a gold shell. A change in AC hysteresis loops was detected before and after the formation of the gold shell on magnetic core nanoparticles, suggesting the influence of the core-shell interfacial effect on their dynamic magnetic properties. This alteration in the dynamic responses resulted in an enhancement of the MPI imaging capacity of magnetic nanoparticles. The gold shell coating also enabled a simple and effective functionalization of the nanoparticles with a brain glioma targeting ligand. The enhanced MPI imaging capacity and effective functionality suggest the potential application of the magnetic-gold core-shell nanoparticles for MPI disease diagnostics.


Asunto(s)
Oro/química , Nanopartículas de Magnetita/química , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Cloruros/química , Medios de Contraste/química , Compuestos Férricos/química , Humanos , Nanopartículas de Magnetita/toxicidad , Microscopía Electrónica de Transmisión , Compuestos de Sulfhidrilo/química
14.
Drug Discov Today ; 24(3): 873-882, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30660756

RESUMEN

Advanced central nervous system (CNS) therapies exhibited high efficacy but complete treatment of CNS diseases remains challenging owing to limited delivery of therapeutic agents to the brain. Multifunctional magnetic nanoparticles are investigated not only for site-specific drug delivery but also for theranostic applications aiming for an effective CNS therapy. Recently, surface engineering of magnetic nanoparticles was recognized as a crucial area of research to achieve precise therapy and imaging at molecular and cellular levels. This review reports state-of-the-art advancement in the development of surface-engineered magnetic nanoparticles targeting CNS diagnostics and therapies. The challenges and future prospects of magnetic theranostics are also discussed by considering the translation from bench to bedside. Successful translation of magnetic theranostics to the clinical setting will enable precise and efficient diagnostics and therapy to manage CNS diseases.


Asunto(s)
Enfermedades del Sistema Nervioso Central/tratamiento farmacológico , Nanopartículas/administración & dosificación , Animales , Sistemas de Liberación de Medicamentos , Humanos , Fenómenos Magnéticos , Nanopartículas/química , Propiedades de Superficie , Distribución Tisular
15.
Sci Rep ; 9(1): 3928, 2019 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-30850620

RESUMEN

CRISPR-Cas9/gRNA exhibits therapeutic efficacy against latent human immunodeficiency virus (HIV) genome but the delivery of this therapeutic cargo to the brain remains as a challenge. In this research, for the first time, we demonstrated magnetically guided non-invasive delivery of a nano-formulation (NF), composed of Cas9/gRNA bound with magneto-electric nanoparticles (MENPs), across the blood-brain barrier (BBB) to inhibit latent HIV-1 infection in microglial (hµglia)/HIV (HC69) cells. An optimized ac-magnetic field of 60 Oe was applied on NF to release Cas9/gRNA from MENPs surface and to facilitate NF cell uptake resulting in intracellular release and inhibition of HIV. The outcomes suggested that developed NF reduced HIV-LTR expression significantly in comparison to unbound Cas9/gRNA in HIV latent hµglia/HIV (HC69) cells. These findings were also validated qualitatively using fluorescence microscopy to assess NF efficacy against latent HIV in the microglia cells. We believe that CNS delivery of NF (CRISPR/Cas9-gRNA-MENPs) across the BBB certainly will have clinical utility as future personalized nanomedicine to manage neuroHIV/AIDS.


Asunto(s)
Barrera Hematoencefálica/virología , Infecciones por VIH/terapia , Infecciones por VIH/virología , VIH-1 , ARN Guía de Kinetoplastida/administración & dosificación , Sistemas CRISPR-Cas , Células Cultivadas , Sistemas de Liberación de Medicamentos , Edición Génica/métodos , VIH-1/genética , Humanos , Técnicas In Vitro , Nanopartículas de Magnetita/administración & dosificación , ARN Guía de Kinetoplastida/genética , Latencia del Virus
16.
Biomed Opt Express ; 9(2): 373-386, 2018 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-29552379

RESUMEN

Engineered terahertz (THz) plasmonic metamaterials have emerged as promising platforms for quick infection diagnosis, cost-effective and real-time pharmacology applications owing to their non-destructive and harmless interaction with biological tissues in both in vivo and in vitro assays. As a recent member of THz metamaterials family, toroidal metamaterials have been demonstrated to be supporting high-quality sharp resonance modes. Here we introduce a THz metasensor based on a plasmonic surface consisting of metamolecules that support ultra-narrow toroidal resonances excited by the incident radiation and demonstrate detection of an ultralow concertation targeted biomarker. The toroidal plasmonic metasurface was designed and optimized through extensive numerical studies and fabricated by standard microfabrication techniques. The surface then functionalized by immobilizing the antibody for virus-envelope proteins (ZIKV-EPs) for selective sensing. We sensed and quantified the ZIKV-EP in the assays by measuring the spectral shifts of the toroidal resonances while varying the concentration. In an improved protocol, we introduced gold nanoparticles (GNPs) decorated with the same antibodies onto the metamolecules and monitored the resonance shifts for the same concentrations. Our studies verified that the presence of GNPs enhances capturing of biomarker molecules in the surrounding medium of the metamaterial. By measuring the shift of the toroidal dipolar momentum (up to Δω~0.35 cm-1) for different concentrations of the biomarker proteins, we analyzed the sensitivity, repeatability, and limit of detection (LoD) of the proposed toroidal THz metasensor. The results show that up to 100-fold sensitivity enhancement can be obtained by utilizing plasmonic nanoparticles-integrated toroidal metamolecules in comparison to analogous devices. This approach allows for detection of low molecular-weight biomolecules (≈13 kDa) in diluted solutions using toroidal THz plasmonic unit cells.

17.
Sci Rep ; 8(1): 12991, 2018 08 28.
Artículo en Inglés | MEDLINE | ID: mdl-30154522

RESUMEN

HIV and substance abuse plays an important role in infection and disease progression. Further, the presence of persistent viral CNS reservoirs makes the complete eradication difficult. Thus, neutralizing the drug of abuse effect on HIV-1 infectivity and elimination of latently infected cells is a priority. The development of a multi-component [antiretroviral drugs (ARV), latency reactivating agents (LRA) and drug abuse antagonist (AT)] sustained release nanoformulation targeting the CNS can overcome the issues of HIV-1 cure and will help in improving the drug adherence. The novel magneto-liposomal nanoformulation (NF) was developed to load different types of drugs (LRAs, ARVs, and Meth AT) and evaluated for in-vitro and in-vivo BBB transmigration and antiviral efficacy in primary CNS cells. We established the HIV-1 latency model using human astrocyte cells (HA) and optimized the dose of LRA for latency reversal, Meth AT in in-vitro cell culture system. Further, PEGylated magneto-liposomal NF was developed, characterized for size, shape, drug loading and BBB transport in-vitro. Results showed that drug released in a sustained manner up to 10 days and able to reduce the HIV-1 infectivity up to ~40-50% (>200 pg/mL to <100 pg/mL) continuously using single NF treatment ± Meth treatment in-vitro. The magnetic treatment (0.8 T) was able to transport (15.8% ± 5.5%) NF effectively without inducing any toxic effects due to NF presence in the brain. Thus, our approach and result showed a way to eradicate HIV-1 reservoirs from the CNS and possibility to improve the therapeutic adherence to drugs in drug abusing (Meth) population. In conclusion, the developed NF can provide a better approach for the HIV-1 cure and a foundation for future HIV-1 purging strategies from the CNS using nanotechnology platform.


Asunto(s)
Astrocitos , Infecciones por VIH/tratamiento farmacológico , VIH-1/fisiología , Nanopartículas , Trastornos Relacionados con Sustancias/tratamiento farmacológico , Latencia del Virus/efectos de los fármacos , Antirretrovirales/química , Antirretrovirales/farmacocinética , Antirretrovirales/farmacología , Astrocitos/metabolismo , Astrocitos/patología , Astrocitos/virología , Células Cultivadas , Infecciones por VIH/metabolismo , Infecciones por VIH/patología , Humanos , Nanomedicina/métodos , Nanopartículas/química , Nanopartículas/uso terapéutico , Trastornos Relacionados con Sustancias/metabolismo , Trastornos Relacionados con Sustancias/patología , Trastornos Relacionados con Sustancias/virología
18.
Nanoscale ; 10(1): 184-194, 2017 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-29210401

RESUMEN

Image-guided drug delivery is an emerging strategy in the field of nanomedicine. The addition of image guidance to a traditional drug delivery system is expected to achieve highly efficient treatment by tracking the drug carriers in the body and monitoring their effective accumulation in the targeted tissues. In this study, we developed multifunctional magneto-plasmonic liposomes (MPLs), a hybrid system combining liposomes and magneto-plasmonic nanoparticles for a triple-modality image-guided drug delivery. Tenofovir disoproxil fumarate, an antiretroviral drug used to treat human immunodeficiency virus type 1 (HIV-1), was encapsulated into the MPLs to enable the treatment in the brain microenvironment, which is inaccessible to most of the drugs. We found strong negative and positive contrasts originating from the magnetic core of MPLs in magnetic resonance imaging (MRI) and magnetic particle imaging (MPI), respectively. The gold shell of MPLs showed bright positive contrast in X-ray computed tomography (CT). MPLs achieved enhanced transmigration across an in vitro blood-brain barrier (BBB) model by magnetic targeting. Moreover, MPLs provided desired therapeutic effects against HIV infected microglia cells.


Asunto(s)
Encéfalo/efectos de los fármacos , Sistemas de Liberación de Medicamentos , Infecciones por VIH/diagnóstico por imagen , Infecciones por VIH/tratamiento farmacológico , Liposomas , Antirretrovirales/administración & dosificación , Barrera Hematoencefálica , Línea Celular , Oro , Humanos , Magnetismo , Nanopartículas del Metal , Microglía/efectos de los fármacos , Microglía/virología , Imagen Multimodal , Nanomedicina , Tenofovir/administración & dosificación
19.
Nanoscale ; 9(2): 764-773, 2017 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-27976764

RESUMEN

Magneto-plasmonic nanoparticles are one of the emerging multi-functional materials in the field of nanomedicine. Their potential for targeting and multi-modal imaging is highly attractive. In this study, magnetic core/gold shell (MNP@Au) magneto-plasmonic nanoparticles were synthesized by citrate reduction of Au ions on magnetic nanoparticle seeds. Hydrodynamic size and optical properties of magneto-plasmonic nanoparticles synthesized with the variation of Au ions and reducing agent concentrations were evaluated. The synthesized magneto-plasmonic nanoparticles exhibited superparamagnetic properties, and their magnetic properties contributed to the concentration-dependent contrast in magnetic resonance imaging (MRI). The imaging contrast from the gold shell part of the magneto-plasmonic nanoparticles was also confirmed by X-ray computed tomography (CT). The transmigration study of the magneto-plasmonic nanoparticles using an in vitro blood-brain barrier (BBB) model proved enhanced transmigration efficiency without disrupting the integrity of the BBB, and showed potential to be used for brain diseases and neurological disorders.


Asunto(s)
Barrera Hematoencefálica , Encéfalo/diagnóstico por imagen , Imagen por Resonancia Magnética , Nanopartículas de Magnetita , Imagen Multimodal , Astrocitos/citología , Encéfalo/citología , Células Cultivadas , Células Endoteliales/citología , Oro , Humanos , Magnetismo , Modelos Biológicos
20.
Nanoscale ; 9(47): 18723-18730, 2017 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-29165498

RESUMEN

Magnetic Particle Imaging (MPI) is an emerging, whole body biomedical imaging technique, with sub-millimeter spatial resolution and high sensitivity to a biocompatible contrast agent consisting of an iron oxide nanoparticle core and a biofunctionalized shell. Successful application of MPI for imaging of cancer depends on the nanoparticles (NPs) accumulating at tumors at sufficient levels relative to other sites. NPs' physiochemical properties such as size, crystallographic structure and uniformity, surface coating, stability, blood circulation time and magnetization determine the efficacy of their tumor accumulation and MPI signal generation. Here, we address these criteria by presenting strategies for the synthesis and surface functionalization of efficient MPI tracers, that can target a typical murine brain cancer model and generate three dimensional images of these tumors with very high signal-to-noise ratios (SNR). Our results showed high contrast agent sensitivities that enabled us to detect 1.1 ng of iron (SNR ∼ 3.9) and enhance the spatial resolution to about 600 µm. The biodistribution of these NPs was also studied using near-infrared fluorescence (NIRF) and single-photon emission computed tomography (SPECT) imaging. NPs were mainly accumulated in the liver and spleen and did not show any renal clearance. This first pre-clinical study of cancer targeted NPs imaged using a tomographic MPI system in an animal model paves the way to explore new nanomedicine strategies for cancer diagnosis and therapy, using clinically safe magnetic iron oxide nanoparticles and MPI.


Asunto(s)
Neoplasias Encefálicas/diagnóstico por imagen , Diagnóstico por Imagen/métodos , Glioma/diagnóstico por imagen , Magnetismo , Nanopartículas , Tomografía , Animales , Línea Celular Tumoral , Femenino , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Ratas , Tomografía Computarizada por Tomografía Computarizada de Emisión de Fotón Único , Distribución Tisular
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