The financial support of the Max-Planck Society, the Turkish Ministry of National Education (PhD fellowship to S. G.), and the German Exchange Academic Service (DAAD, PhD fellowship to T. S.) are gratefully acknowledged.

<ol>
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The authors have nothing to disclose.

Preparación del agente de contraste de MRI dendrimérica requiere la selección apropiada de la unidad monomérica (es decir, el quelante de Gd (III)). Reducen la toxicidad de este ion paramagnético y, hasta la fecha, una gran variedad de acíclicos y quelantes macrocíclicos sirven para este propósito 1-3. Entre estos, macrocíclicos quelantes de tipo DOTA poseen la más alta estabilidad termodinámica e inercia cinética y, por lo tanto, son la opción más preferido para la preparación de agen...

La resonancia magnética (RM) es una técnica de imagen de gran alcance y no ionizantes ampliamente utilizado en la investigación biomédica y el diagnóstico clínico debido a su naturaleza no invasiva y excelente contraste de los tejidos blandos intrínseca. Los métodos de resonancia magnética utilizados más comúnmente utilizan la señal obtenida a partir de los protones del agua, proporcionando imágenes de alta resolución e información detallada dentro de los tejidos en base a las diferencias en la densidad de las señales de agua. La intensidad de la señal y la especificidad de los experimentos de resonancia magnética se pueden mejorar aún más el uso de agentes de contraste (CAS). Estos son especies paramagnéticas o superparamagnéticas que afectan a la longitudinal (T 1) y transversal (T 2) tiempos de relajación, respectivamente 1,2. Los complejos de gadolinio de iones lantánidos con ligandos de ácido poliamino policarboxílicos son los más comúnmente utilizados T 1 AC. Gadolinio (III) acorta la relajación T 1tiempo de protones del agua, lo que aumenta el contraste de la señal en la RM experimentos 3. Sin embargo, el gadolinio iónico es tóxico; su tamaño se aproxima al de calcio (II), y afecta seriamente calcio asistida señalización en las células. Por lo tanto, se emplean acíclicos y macrocíclicos quelatos para neutralizar esta toxicidad. Varios ligandos polidentados se han desarrollado hasta el momento, dando como resultado complejos de gadolinio (III) con alta estabilidad termodinámica e inercia cinética 1. Los basados ​​en los cyclen azamacrocycle de 12 miembros, en particular, su tetracarboxílico DOTA derivado (1,4,7,10-tetraazaciclododecano-1,4,7,10-tetraacetato) son los complejos más investigados y aplicados de esta clase CA. Sin embargo, de tipo GdDOTA CAs son sistemas de bajo peso molecular, que presentan ciertas desventajas tales como la baja eficiencia de contraste y la excreción renal rápido. Macromolecular y multivalente entidades emisoras pueden ser una buena solución a estos problemas 4. Desde CA biodistribución está determinada principalmente por su tamaño, AC macromoleculares muestran tiempos de retención más largos dentro de los tejidos. Igualmente importante, la polivalencia de estos agentes da como resultado un aumento de la concentración local de la sonda monomérica MR (por ejemplo, complejo GdDOTA), mejorando sustancialmente la señal de MR adquirida y la calidad de la medición. Los dendrímeros son algunos de los andamios más preferidos para la preparación de multivalente CAs para MRI 4,5. Estas macromoléculas altamente ramificadas con tamaños bien definidos son propensos a diversas reacciones de acoplamiento en su superficie. En este trabajo se reporta la preparación, purificación y caracterización de un dendrímero CA para la resonancia magnética que consiste en un poli 4 (G4) generación (amidoamina) (PAMAM) dendrímero acoplado a quelatos GdDOTA-como (DCA). Se describe la síntesis del derivado de DOTA reactivo y su acoplamiento al dendrímero PAMAM. Tras la formación de complejos con Gd (III), la caracterización físico-química estándar procedire de DCA se realizó. Por último, se realizaron experimentos de resonancia magnética para demostrar la capacidad de DCA para producir imágenes de RM con un contraste más fuerte que los obtenidos de bajo peso molecular CAs.

<table><tbody><tr><td>Cyclen</td><td>CheMatech</td><td>C002</td><td></td></tr><tr><td>&lt;em&gt;tert&lt;/em&gt;-Butyl bromoacetate&amp;nbsp;</td><td>Alfa Aesar</td><td>A14917</td><td></td></tr><tr><td>&lt;em&gt;N,N&lt;/em&gt;-Dimethylformamide</td><td>Fluka</td><td>40248</td><td></td></tr><tr><td>Potassium carbonate</td><td>Sigma-Aldrich</td><td>209619</td><td></td></tr><tr><td>4-(4-Nitrophenyl)butryic acid</td><td>Aldrich</td><td>335339</td><td></td></tr><tr><td>Thionyl chloride&amp;nbsp;</td><td>Acros Organics</td><td>382662500</td><td>Note: Corrosive substance; toxic if inhaled</td></tr><tr><td>Bromine</td><td>Acros Organics</td><td>402841000</td><td>Note: causes severe skin burns, fatal if inhaled&amp;nbsp;</td></tr><tr><td>Diethyl ether</td><td>any source</td><td></td><td></td></tr><tr><td>Sodium sulphate</td><td>Acros Organics</td><td>196640010</td><td></td></tr><tr><td>Chloroform&amp;nbsp;</td><td>VWR Chemicals</td><td>22711.29</td><td></td></tr><tr><td>&lt;em&gt;tert&lt;/em&gt;-Butyl 2,2,2-trichloroacetimidate</td><td>Aldrich</td><td>364789</td><td>Note: flammable substance; irritrant to skin and eyes</td></tr><tr><td>Boron trifluoride etherate</td><td>Acros Organics</td><td>174560250</td><td>48% BF&lt;sub&gt;3&lt;/sub&gt;. Note: Flammable substance; causes skin burns, fatal if inhaled</td></tr><tr><td>Sodium bicarbonate</td><td>Acros Organics</td><td>424270010</td><td></td></tr><tr><td>Ethyl-acetate</td><td>any source</td><td></td><td>For column chromatography</td></tr><tr><td>&lt;em&gt;n&lt;/em&gt;-Hexane</td><td>any source</td><td></td><td>For column chromatography</td></tr><tr><td>Bulb-to-bulb (Kugelrohr) distillation apparatus</td><td>B&amp;uuml;chi</td><td></td><td>Model type: Glass oven B-585</td></tr><tr><td>Silicagel</td><td>Carl Roth GmbH</td><td>P090.2</td><td></td></tr><tr><td>Methanol</td><td>any source</td><td></td><td>For column chromatography</td></tr><tr><td>Dichloromethane&amp;nbsp;</td><td>any source</td><td></td><td>For column chromatography</td></tr><tr><td>Ethanol</td><td>VWR Chemicals</td><td>20821.296</td><td></td></tr><tr><td>Ammonia</td><td>Acros Organics</td><td>428381000</td><td>7 N Solution in Methanol</td></tr><tr><td>Palladium</td><td>Aldrich</td><td>643181</td><td>15% wet</td></tr><tr><td>Hydrogenation apparatus PARR</td><td>PARR Instrument Company</td><td></td><td></td></tr><tr><td>Celite 503</td><td>Aldrich</td><td>22151</td><td></td></tr><tr><td>Sintered glass funnel</td><td>any source</td><td></td><td></td></tr><tr><td>Thiophosgen</td><td>Aldrich</td><td>115150</td><td>Note: irritrant to skin; toxic if inhaled</td></tr><tr><td>Triethylamine</td><td>Alfa Aesar</td><td>A12646</td><td></td></tr><tr><td>Dichloromethane&amp;nbsp;</td><td>Acros Organics</td><td>348460010</td><td>Extra dry&amp;nbsp;</td></tr><tr><td>Magnetic stirrer</td><td>any source</td><td></td><td></td></tr><tr><td>PAMAM G4 Dendrimer</td><td>Andrews ChemService</td><td>AuCS - 297</td><td>10% wt. solution in MeOH</td></tr><tr><td>Lipophylic Sephadex LH-20</td><td>Sigma</td><td>LH20100</td><td></td></tr><tr><td>Thin-layer chromatography plates</td><td>Merck Millipore</td><td>1.05554.0001</td><td></td></tr><tr><td>Formic acid</td><td>VWR Chemicals</td><td>20318.297</td><td></td></tr><tr><td>Lophylizer&amp;nbsp;</td><td>any source</td><td></td><td></td></tr><tr><td>Gadollinium(III) chloride hexahydrate</td><td>Aldrich</td><td>G7532</td><td></td></tr><tr><td>Sodium hydroxide</td><td>Acros Organics</td><td>134070010</td><td></td></tr><tr><td>pH meter</td><td>any source</td><td></td><td></td></tr><tr><td>Ethylenediaminetetraacetic acid disodium salt dihydrate</td><td>Aldrich</td><td>E5134</td><td></td></tr><tr><td>Mass spectrometer (ESI)</td><td>Agilent</td><td></td><td>Ion trap SL 1100&amp;nbsp;</td></tr><tr><td>Acetate buffer</td><td>any source</td><td></td><td>pH 5.8</td></tr><tr><td>Xylenol orange</td><td>Aldrich</td><td>52097</td><td>20 &amp;mu;M in acetate buffer</td></tr><tr><td>Hydrophylic Sephadex G-15</td><td>GE Healthcare</td><td>17-0020-01</td><td></td></tr><tr><td>Amicon Ultra-15 Centrifugal Filter Unit</td><td>Merck Millipore</td><td>UFC900324</td><td>Ultracel-3 membrane (MWCO 3000)</td></tr><tr><td>Centrifuge</td><td>any source</td><td></td><td></td></tr><tr><td>NMR spectrometer&amp;nbsp;</td><td>Bruker</td><td></td><td>Avance III 300 MHz</td></tr><tr><td>Topspin</td><td>Bruker</td><td></td><td>Version 2.1</td></tr><tr><td>Combustion analysis instrument</td><td>EuroVector SpA</td><td></td><td>EuroEA 3000 Elemental Analyser&amp;nbsp;</td></tr><tr><td>MALDI-ToF MS instrument</td><td>Applied Biosystems</td><td></td><td>Voyager-STR</td></tr><tr><td>Deuteriumoxid</td><td>Carl Roth GmbH</td><td>6672.3</td><td></td></tr><tr><td>&lt;em&gt;tert&lt;/em&gt;-Butyl alcohol</td><td>Carl Roth GmbH</td><td>AE16.1</td><td></td></tr><tr><td>Vortex mixer</td><td>any source</td><td></td><td></td></tr><tr><td>Norell NMR tubes</td><td>Deutero GmbH</td><td>507-HP-7</td><td></td></tr><tr><td>NMR coaxial tube</td><td>Deutero GmbH</td><td>coaxialb-5-7</td><td></td></tr><tr><td>DLS instrument</td><td>Malvern</td><td></td><td>Zetasizer Nano ZS</td></tr><tr><td>0.20 &amp;mu;m PTFE filter&amp;nbsp;</td><td>Carl Roth GmbH</td><td>KC94.1</td><td></td></tr><tr><td>HEPES</td><td>Fisher BioReagents</td><td>BP310</td><td></td></tr><tr><td>Plastic tube vials</td><td>any source</td><td></td><td></td></tr><tr><td>Dotarem</td><td>Guerbet</td><td></td><td>NDC 67684-2000-1</td></tr><tr><td>MRI scanner</td><td>Bruker</td><td></td><td>BioSpec 70/30 USR magnet (7 T). Note: potential hazards related to high magnetic fields</td></tr><tr><td>RF coil</td><td>Bruker</td><td></td><td>Dual frequency volume coil (RF RES 300 1H/19F 075/040 LIN/LIN TR)</td></tr><tr><td>Paravision (software)</td><td>Bruker</td><td></td><td>Version 5.1</td></tr></tbody></table>

preparation and in vitro characterization of dendrimer-based contrast agents for magnetic resonance imaging

complejos paramagnéticos de gadolinio (III) con acíclico o quelatos macrocíclicos son los agentes de contraste más utilizados (CAS) para la formación de imágenes por resonancia magnética (MRI). Su propósito es mejorar la velocidad de relajación de protones del agua en el tejido, aumentando así el contraste de la imagen MR y la especificidad de las mediciones de resonancia magnética. Los agentes de contraste clínicamente aprobados actuales son moléculas de bajo peso molecular que se eliminan rápidamente del cuerpo. El uso de dendrímeros como portadores de quelantes paramagnéticas puede desempeñar un papel importante en el futuro desarrollo de agentes de contraste para MRI más eficientes. En concreto, el aumento de la concentración local de los resultados especie paramagnética en un mayor contraste de la señal. Además, esta CA proporciona un tiempo de retención de tejido más largo debido a su alto peso molecular y el tamaño. Aquí, se demuestra un procedimiento conveniente para la preparación de agentes de contraste macromoleculares de resonancia magnética a base de poli (amidoamina) (PAMAM) con monomacrocíclicos quelantes de tipo DOTA (DOTA - 1,4,7,10-tetraazaciclododecano-1,4,7,10-tetraacetato). La unidad quelante se adjuntó explotando la reactividad del grupo isotiocianato (NCS) hacia los grupos de superficie amina del dendrímero PAMAM para formar puentes de tiourea. productos dendrímeros se purificaron y se analizaron por medio de espectroscopía de resonancia magnética nuclear, espectrometría de masas y análisis elemental. Por último, de alta resolución las imágenes de RM se registraron y se compararon los contrastes de señal obtenidos a partir de la dendrimérica preparados y los agentes monoméricos disponibles comercialmente.

La preparación de DCA consistía en dos etapas: 1) la síntesis del quelante monomérica de tipo DOTA (Figura 1) y 2) de acoplamiento del quelante con el dendrímero G4 PAMAM y la posterior preparación del Gd dendrimérica (III) (Figura 2) . En la primera etapa, se preparó una de tipo DOTA quelante basado en cyclen que contiene cuatro ácidos carboxílicos y un grupo ortogonal adecuado para otras modificaciones sintéticas. La prepara...

Watch this Scientific Journal Video about Preparation and In Vitro Characterization of Dendrimer-based Contrast Agents for Magnetic Resonance Imaging at JoVE.com

Preparation and In Vitro Characterization of Dendrimer-based Contrast Agents for Magnetic Resonance Imaging

Este protocolo describe la preparación y caracterización de un agente de contraste dendrimérica imágenes de resonancia magnética (MRI) que lleva a base cyclen-quelatos macrocíclicos de coordinación iones paramagnéticos de gadolinio. En una serie de experimentos de resonancia magnética en vitro, este agente produce una señal de MRI amplificado en comparación con el análogo monomérico disponible comercialmente.

Preparación y<em&gt; In Vitro</em&gt; Caracterización de los agentes de contraste basados ​​en dendrímeros de Imágenes por Resonancia Magnética

Paramagnetic complexes of gadolinium(III) with acyclic or macrocyclic chelates are the most commonly used contrast agents (CAs) for magnetic resonance ...

preparation-vitro-characterization-dendrimer-based-contrast-agents

Universidad de Cartagena UDEC

Research

JoVE Journal

Chemistry

Preparation and In Vitro Characterization of Dendrimer-based Contrast Agents for Magnetic Resonance Imaging

9.8K vistas.  Max Planck Institute for Biological Cybernetics.  Este protocolo describe la preparación y caracterización de un agente de contraste dendrimérica imágenes de resonancia magnética (MRI) que lleva a base cyclen-quelatos macrocíclicos de coordinación iones paramagnéticos de gadolinio. En una serie de experimentos de resonancia magnética en vitro, este agente produce una señal de MRI amplificado en comparación con el análogo monomérico disponible comercialmente. 

Video: Preparation and In Vitro Characterization of Dendrimer-based Contrast Agents for Magnetic Resonance Imaging

Registered Bioimaging of Nanomaterials for Diagnostic and Therapeutic Monitoring

Nanomedications can be carried by blood borne monocyte-macrophages into the reticuloendothelial system (RES; spleen, liver, lymph nodes) and to end organs. The latter include the lung, RES, and brain and are operative during human immunodeficiency virus type one (HIV-1) infection. Macrophage entry into tissues is notable in areas of active HIV-1 replication and sites of inflammation. In order to assess the potential of macrophages as nanocarriers, superparamagnetic iron-oxide and/or drug laden particles coated with surfactants were parenterally injected into HIV-1 encephalitic mice. This was done to quantitatively assess particle and drug biodistribution. Magnetic resonance imaging (MRI) test results were validated by histological coregistration and enhanced image processing. End organ disease as typified by altered brain histology were assessed by MRI. The demonstration of robust migration of nanoformulations into areas of focal encephalitis provides '"proof of concept" for the use of advanced bioimaging techniques to monitor macrophage migration. Importantly, histopathological aberrations in brain correlate with bioimaging parameters making the general utility of MRI in studies of cell distribution in disease feasible. We posit that using such methods can provide a real time index of disease burden and therapeutic efficacy with translational potential to humans.

Bioimaging methods used to assess cell biodistribution of nanoparticles are applicable for therapeutic and diagnostic monitoring of nanoformulated compounds. The methods described herein are sensitive and specific when assessed by histological coregistration. The methodologies provide a translational pathway from rodent to human applications.

Bioimagen registradas de Nanomateriales para el Monitoreo de Diagnóstico y Terapéutica

Nanomedications can be carried by blood borne monocyte-macrophages into the reticuloendothelial system (RES; spleen, liver, lymph nodes) and to end ...

Investigación

Bioingeniería

Synthesis, Cellular Delivery and In vivo Application of Dendrimer-based pH Sensors

The development of fluorescent indicators represented a revolution for life sciences. Genetically encoded and synthetic fluorophores with sensing abilities allowed the visualization of biologically relevant species with high spatial and temporal resolution. Synthetic dyes are of particular interest thanks to their high tunability and the wide range of measureable analytes. However, these molecules suffer several limitations related to small molecule behavior (poor solubility, difficulties in targeting, often no ratiometric imaging allowed). In this work we introduce the development of dendrimer-based sensors and present a procedure for pH measurement in vitro, in living cells and in vivo. We choose dendrimers as ideal platform for our sensors for their many desirable properties (monodispersity, tunable properties, multivalency) that made them a widely used scaffold for several biomedical devices. The conjugation of fluorescent pH indicators to the dendrimer scaffold led to an enhancement of their sensing performances. In particular dendrimers exhibit reduced cell leakage, improved intracellular targeting and allow ratiometric measurements. These novel sensors were successfully employed to measure pH in living HeLa cells and in vivo in mouse brain.

Synthesis, Cellular Delivery and In vivo Application of Dendrimer-based pH Sensors

Fluorescence sensors are powerful tools in life science. Here we describe a methodology to synthesize and use dendrimer-based fluorescent sensors to measure pH in living cells and in vivo. The dendritic scaffold enhances the properties of conjugated fluorescent dyes leading to improved sensing properties.

Síntesis, Entrega y Celular<em&gt; En vivo</em&gt; Aplicación de sensores de pH basadas en dendrímeros

The development of  fluorescent indicators represented a revolution for life sciences. Genetically  encoded and synthetic fluorophores with sensing ...

Química

In vitro Labeling of Human Embryonic Stem Cells for Magnetic Resonance Imaging

Human embryonic stem cells (hESC) have demonstrated the ability to restore the injured myocardium. Magnetic resonance imaging (MRI) has emerged as one of the predominant imaging modalities to assess the restoration of the injured myocardium. Furthermore, ex-vivo labeling agents, such as iron-oxide nanoparticles, have been employed to track and localize the transplanted stem cells. However, this method does not monitor a fundamental cellular biology property regarding the viability of transplanted cells. It has been known that manganese chloride (MnCl2) enters the cells via voltage-gated calcium (Ca2+) channels when the cells are biologically active, and accumulates intracellularly to generate T1 shortening effect. Therefore, we suggest that manganese-guided MRI can be useful to monitor cell viability after the transplantation of hESC into the myocardium.
In this video, we will show how to label hESC with MnCl2 and how those cells can be clearly seen by using MRI in vitro. At the same time, biological activity of Ca2+-channels will be modulated utilizing both Ca2+-channel agonist and antagonist to evaluate concomitant signal changes.

In this video, we are showing how to label human embryonic stem cells (hESC) with manganese chloride (MnCl2) which can enter cells via voltage-gated calcium channels when the cells are biologically active. Additionally, we show the use of MnCl2 as cellular MRI contrast agent to determine the in vitro viability of hESC.

En el etiquetado in vitro de células estaminales embrionarias humanas de Resonancia Magnética

Human embryonic stem cells (hESC) have demonstrated the ability to restore the injured myocardium. Magnetic resonance imaging (MRI) has emerged as one of ...

Biología

Monitoring Dendritic Cell Migration using 19F / 1H Magnetic Resonance Imaging

Continuous advancements in noninvasive imaging modalities such as magnetic resonance imaging (MRI) have greatly improved our ability to study physiological or pathological processes in living organisms. MRI is also proving to be a valuable tool for capturing transplanted cells in vivo. Initial cell labeling strategies for MRI made use of contrast agents that influence the MR relaxation times (T1, T2, T2*) and lead to an enhancement (T1) or depletion (T2*) of signal where labeled cells are present. T2* enhancement agents such as ultrasmall iron oxide agents (USPIO) have been employed to study cell migration and some have also been approved by the FDA for clinical application. A drawback of T2* agents is the difficulty to distinguish the signal extinction created by the labeled cells from other artifacts such as blood clots, micro bleeds or air bubbles. In this article, we describe an emerging technique for tracking cells in vivo that is based on labeling the cells with fluorine (19F)-rich particles. These particles are prepared by emulsifying perfluorocarbon (PFC) compounds and then used to label cells, which subsequently can be imaged by 19F MRI. Important advantages of PFCs for cell tracking in vivo include (i) the absence of carbon-bound 19F in vivo, which then yields background-free images and complete cell selectivityand(ii) the possibility to quantify the cell signal by 19F MR spectroscopy.

Monitoring Dendritic Cell Migration using 19F / 1H Magnetic Resonance Imaging

Tracking of cells using MRI has gained remarkable attention in the past years. This protocol describes the labeling of dendritic cells with fluorine (19F)-rich particles, the in vivo application of these cells, and monitoring the extent of their migration to the draining lymph node with 19F/1H MRI and 19F MRS.

De las Migraciones células dendríticas mediante resonancia 19F / 1H Magnetic

Continuous  advancements in noninvasive imaging modalities such as magnetic resonance  imaging (MRI) have greatly improved our ability to study ...

Inmunología e Infección

MR Molecular Imaging of Prostate Cancer with a Small Molecular CLT1 Peptide Targeted Contrast Agent

Tumor extracellular matrix has abundance of cancer related proteins that can be used as biomarkers for cancer molecular imaging. In this work, we demonstrated effective MR cancer molecular imaging with a small molecular peptide targeted Gd-DOTA monoamide complex as a targeted MRI contrast agent specific to clotted plasma proteins in tumor stroma. We performed the experiment of evaluating the effectiveness of the agent for non-invasive detection of prostate tumor with MRI in a mouse orthotopic PC-3 prostate cancer model. The targeted contrast agent was effective to produce significant tumor contrast enhancement at a low dose of 0.03 mmol Gd/kg. The peptide targeted MRI contrast agent is promising for MR molecular imaging of prostate tumor.

To demonstrate MR cancer molecular imaging with a small peptide targeted MRI contrast agent specific to clotted plasma proteins in tumor stroma in a mouse prostate cancer model.

MR Imagen Molecular del cáncer de próstata con un agente de contraste dirigidos Pequeño Molecular CLT1 Péptido

Tumor extracellular  matrix has abundance of cancer related proteins that can be used as biomarkers  for cancer molecular imaging. In this work,  we ...

Medicina

Biofunctionalized Prussian Blue Nanoparticles for Multimodal Molecular Imaging Applications

Multimodal, molecular imaging allows the visualization of biological processes at cellular, subcellular, and molecular-level resolutions using multiple, complementary imaging techniques. These imaging agents facilitate the real-time assessment of pathways and mechanisms in vivo, which enhance both diagnostic and therapeutic efficacy. This article presents the protocol for the synthesis of biofunctionalized Prussian blue nanoparticles (PB NPs) - a novel class of agents for use in multimodal, molecular imaging applications. The imaging modalities incorporated in the nanoparticles, fluorescence imaging and magnetic resonance imaging (MRI), have complementary features. The PB NPs possess a core-shell design where gadolinium and manganese ions incorporated within the interstitial spaces of the PB lattice generate MRI contrast, both in T1 and T2-weighted sequences. The PB NPs are coated with fluorescent avidin using electrostatic self-assembly, which enables fluorescence imaging. The avidin-coated nanoparticles are modified with biotinylated ligands that confer molecular targeting capabilities to the nanoparticles. The stability and toxicity of the nanoparticles are measured, as well as their MRI relaxivities. The multimodal, molecular imaging capabilities of these biofunctionalized PB NPs are then demonstrated by using them for fluorescence imaging and molecular MRI in vitro.

This protocol describes the synthesis of biofunctionalized Prussian blue nanoparticles and their use as multimodal, molecular imaging agents. The nanoparticles have a core-shell design where gadolinium or manganese ions within the nanoparticle core generate MRI contrast. The biofunctional shell contains fluorophores for fluorescence imaging and targeting ligands for molecular targeting.

Biofuncionalizadas prusiana nanopartículas azul para Multimodal Molecular Aplicaciones de imágenes

Multimodal, molecular imaging allows the visualization of biological processes at cellular, subcellular, and molecular-level resolutions using multiple, ...

In vivo 19F MRI for Cell Tracking

In vivo 19F MRI allows quantitative cell tracking without the use of ionizing radiation. It is a noninvasive technique that can be applied to humans. Here, we describe a general protocol for cell labeling, imaging, and image processing. The technique is applicable to various cell types and animal models, although here we focus on a typical mouse model for tracking murine immune cells. The most important issues for cell labeling are described, as these are relevant to all models. Similarly, key imaging parameters are listed, although the details will vary depending on the MRI system and the individual setup. Finally, we include an image processing protocol for quantification. Variations for this, and other parts of the protocol, are assessed in the Discussion section. Based on the detailed procedure described here, the user will need to adapt the protocol for each specific cell type, cell label, animal model, and imaging setup. Note that the protocol can also be adapted for human use, as long as clinical restrictions are met.

In vivo 19F MRI for Cell Tracking

We describe a general protocol for in vivo cell tracking using MRI in a mouse model with ex vivo labeled cells. A typical protocol for cell labeling, image acquisition processing and quantification is included.

In vivo MRI de 19F para el seguimiento de la célula

In vivo 19F MRI allows quantitative cell tracking without the use of ionizing radiation. It is a noninvasive technique that can be applied to humans. ...

<meta charset="utf8"></head><body>Nanopartículas de óxido de hierro para la administración de terapia guiada por imágenes en el glioblastoma murino

Nanoparticle Delivery of an Oligonucleotide Payload in a Glioblastoma Multiforme Animal Model

Glioblastoma multiforme (GBM) is the most common and aggressive form of primary brain malignancy for which there is no cure. The blood-brain barrier is a significant hurdle in the delivery of therapies to GBM. Reported here is an image-guided, iron oxide-based therapeutic delivery nano platform capable of bypassing this physiological barrier by virtue of size and accumulating in the tumor region, delivering its payload. This 25 nm nano platform consists of crosslinked dextran-coated iron oxide nanoparticles labeled with Cy5.5 fluorescent dye and containing antisense oligonucleotide as a payload. The magnetic iron oxide core enables tracking of the nanoparticles through in vivo magnetic resonance imaging, while Cy5.5 dye allows tracking by optical imaging. This report details the monitoring of the accumulation of this nanoparticle platform (termed MN-anti-miR10b) in orthotopically implanted glioblastoma tumors following intravenous injection. In addition, it provides insight into the in vivo delivery of RNA oligonucleotides, a problem that has hampered the translation of RNA therapeutics into the clinic.

<meta charset="utf8"></head><body>Autor destacado: Terapias innovadoras contra el cáncer con nanopartículas de óxido de hierro para el tratamiento del glioblastoma

The blood-brain barrier is a significant hurdle in the delivery of therapies for glioblastoma, a disease for which there is no cure. Here, we report an in vivo image-guided iron oxide therapeutic nano platform that can bypass this physiological barrier by virtue of size and accumulate in the tumor.

Entrega de nanopartículas de una carga útil de oligonucleótidos en un modelo animal de glioblastoma multiforme

Glioblastoma multiforme (GBM) is the most common and aggressive form of primary brain malignancy for which there is no cure. The blood-brain barrier is a ...

Preparación y

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Capítulos en este video

Bioimagen registradas de Nanomateriales para el Monitoreo de Diagnóstico y Terapéutica

Síntesis, Entrega y Celular

En el etiquetado in vitro de células estaminales embrionarias humanas de Resonancia Magnética

De las Migraciones células dendríticas mediante resonancia 19F / 1H Magnetic

MR Imagen Molecular del cáncer de próstata con un agente de contraste dirigidos Pequeño Molecular CLT1 Péptido

Biofuncionalizadas prusiana nanopartículas azul para Multimodal Molecular Aplicaciones de imágenes

In vivo MRI ^{de 19F} para el seguimiento de la célula

Entrega de nanopartículas de una carga útil de oligonucleótidos en un modelo animal de glioblastoma multiforme

Entrega de nanopartículas de una carga útil de oligonucleótidos en un modelo animal de glioblastoma multiforme

Entrega de nanopartículas de una carga útil de oligonucleótidos en un modelo animal de glioblastoma multiforme