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.

Dendrimeric MRT-kontrast maddesinin hazırlanması monomerik birimin uygun seçimi gerektirir (örneğin, GD şelatör (III)). Bu paramanyetik iyonun toksisitesini azaltmak ve bugüne kadar, asiklik çeşitli ve makrosiklik kenetleme maddeleri bu amaca 1-3 karşılık vermektedir. Bunlar arasında, makrosiklik DOTA tip kıskaçlar yüksek termodinamik kararlılık ve kinetik hareketsizlik sahip ve bu nedenle, eylemsiz bir MRT-kontrast maddesinin 1,18 hazırlanması için en çok tercih edi...

Manyetik rezonans görüntüleme (MRG) nedeniyle invazif olmayan doğası ve mükemmel iç yumuşak doku kontrast yaygın biyomedikal araştırmalar ve klinik teşhis kullanılan güçlü ve iyonize olmayan bir görüntüleme tekniğidir. En sık kullanılan MRG yöntemleri su sinyallerinin yoğunluğu farklılıklara dayalı dokular içinde yüksek çözünürlüklü görüntüler ve ayrıntılı bilgi veren, su proton elde edilen sinyalin kullanmaktadır. sinyal yoğunluğu ve MR deneyler özgüllüğü, bundan başka kontrast maddeleri (CA) kullanılarak geliştirilebilir. Bunlar paramanyetik veya Süperparamanyetik uzunlamasına (T 1) ve enine etkileyen türler (T 2) gevşeme süreleri sırasıyla 1,2 bulunmaktadır. Poli polikarboksilik asit ligandları ile lantanide iyon gadolinyum kompleksleri en sık kullanılan T 1 CA vardır. Gadolinyum (III) T1 gevşeme kısaltırSu protonların zaman, böylece MR deneylerde 3 sinyal kontrastını artırarak. Bununla birlikte, iyonik gadolinyum zehirlidir; boyutu (ii) kalsiyum yaklaşır ve ciddi kalsiyum destekli hücrelerde sinyal etkiler. Bu nedenle, asiklik ve makrosiklik şelatları Bu toksisite nötralize etmek için kullanılır. Çeşitli multidentat ligandlar yüksek termodinamik stabilite ve kinetik inertlik 1 gadolinyum (III) kompleksleri ile sonuçlanır kadar geliştirilmiştir. Özellikle onun tetrakarboksilik türevi DOTA (1,4,7,10-tetraazasiklododekan-1,4,7,10-tetraasetat) 12 üyeli azamacrocycle Cyclen dayalı olanlar, bu CA sınıfının en araştırılmış ve uygulamalı kompleksleri bulunmaktadır. Bununla birlikte, GdDOTA-tipi CA, düşük kontrast verimliliği ve hızlı renal atılım gibi bazı dezavantajları gösteren düşük moleküler ağırlıklı sistemlerdir. Makromoleküler ve çok değerlikli CA bu sorunlara 4 için iyi bir çözüm olabilir. CA biodistribu yanation esas olarak boyutuna göre belirlenir, makromoleküler CA dokular içinde çok daha uzun saklama süreleri gösterir. Eşit derecede önemli, büyük ölçüde elde edilen MR sinyal ve ölçüm kalitesinin iyileştirilmesi monomerik MR prob (örneğin, GdDOTA kompleks), bir artış lokal konsantrasyonunu bu maddeler sonuçlarının çok değerlilik. Dendrimers MRG 4,5 için çok değerlikli CA&#39;ların hazırlanması için en çok tercih edilen iskeleler arasındadır. iyi tanımlanmış boyutları ile bu yüksek ölçüde dallı makromoleküller yüzeyleri çeşitli birleştirme reaksiyonları yatkındır. Bu çalışmada, bir nesil 4 (G4) poli (amidoamin) GdDOTA benzeri şelatları (DCA) birleştirilmiş (tein) dendrimer oluşan MRG için bir dendrimeric CA hazırlanmasını, saflaştırma ve karakterizasyonu rapor. Bu reaktif DOTA türevinin sentezi ve tein dendrimer olan kuplaj tarif eder. Gd (III), standart fiziksel karakterizasyonu ile kompleks halinde süreçleDCA yeniden yapıldı. Son olarak, MR deneyler düşük molekül ağırlıklı bir CA elde edilenlere nazaran daha güçlü bir kontrast MR görüntüleri üretmek için DCA yeteneğini göstermek için yapıldı.

<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

asiklik veya makrosiklik şelatlar ile gadolinyum (III) paramanyetik kompleksleri manyetik rezonans görüntüleme (MRG) için en sık kullanılan kontrast maddeler (CA) bulunmaktadır. Bunların amacı, böylece MR kontrast ve MR, ölçümlerin özgüllüğünün arttırılması, doku su protonlarının gevşeme oranının arttırılmasıdır. Mevcut Klinik olarak onaylanmış kontrast maddeleri hızlı bir şekilde vücuttan, düşük molekül ağırlıklı moleküllerdir. para-manyetik kenetleyiciler taşıyıcıları olarak dendrimerler kullanılması daha verimli MRT-kontrast maddeleri gelecekteki gelişimi önemli bir rol oynayabilir. Spesifik olarak, daha yüksek bir sinyal aksine paramanyetik türler sonuçları yerel konsantrasyonu artar. Ayrıca, bu, CA, yüksek molekül ağırlığı ve büyüklüğü nedeniyle daha uzun bir doku tutma süresi sağlar. Burada, poli (amido) göre makromoleküler MRI kontrast ajanları (tein) monomacro dendrimerlerinde hazırlanması için uygun bir prosedür göstermekhalkalı DOTA-tipi kıskaçlar (DOTA - 1,4,7,10-tetraazasiklododekan-1,4,7,10-tetraasetat). kenetleme birimi tiyoüre köprüleri oluşturmak için tein dendrimer amin yüzey gruplarına yönelik izotiyosiyanat (NCS) grubun reaktivitesini istismar ederek sonuna eklenmiştir. Dendrimeric ürünleri saflaştınldı ve nükleer manyetik rezonans spektroskopisi, kütle spektrometrisi ve elementel analiz vasıtasıyla analiz edildi. Son olarak, yüksek çözünürlüklü MR görüntüleri kaydedildi ve hazırlanan dendrimeric ve piyasada mevcut monomerik ajanlar elde edilen sinyal kontrastlar karşılaştırıldı.

DCA hazırlanması iki aşamadan oluşmaktadır: 1) monomerik DOTA tipi tuzunun sentezi (Şekil 1) ve G4 tein dendrimer ve karmaşık dendrimeric Gd (III) daha sonra hazırlanması kenetleyici 2) bağlantı elemanı (Şekil 2) . İlk aşamada, dört karboksilik asitler ihtiva eden bir Cyclen tabanlı DOTA tipi şelatlayıcı olabilir ve başka bir sentetik modifikasyon için uygun olan bir dik grup elde edilmiştir. Tert-butil 2...

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

Bu protokol paramanyetik gadolinyum iyonları koordine Cyclen tabanlı makrosiklik şelatları taşıyan bir dendrimeric manyetik rezonans görüntüleme (MRG) kontrast madde hazırlanması ve karakterizasyonu açıklar. Ticari olarak temin edilebilen monomerik analog ile karşılaştırıldığında, in vitro olarak MR deneyler serisinde, bu madde bir güçlendirilmiş MR sinyal üretti.

Hazırlama ve<em&gt; İn Vitro</em&gt; Manyetik Rezonans Görüntüleme için Dendrimer tabanlı Kontrast Ajanlar Karakterizasyonu

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

Research

JoVE Journal

Chemistry

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

9.8K Görüntüleme.  Max Planck Institute for Biological Cybernetics.  Bu protokol paramanyetik gadolinyum iyonları koordine Cyclen tabanlı makrosiklik şelatları taşıyan bir dendrimeric manyetik rezonans görüntüleme (MRG) kontrast madde hazırlanması ve karakterizasyonu açıklar. Ticari olarak temin edilebilen monomerik analog ile karşılaştırıldığında, in vitro olarak MR deneyler serisinde, bu madde bir güçlendirilmiş MR sinyal üretti. 

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.

Teşhis ve Tedavi İzleme Nanomalzemelerin Kayıtlı bio

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

Biyomühendislik

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.

Sentez, Hücresel Teslimat ve<em&gt; In vivo</em&gt; Dendrimer tabanlı pH Sensörlerin Uygulamaları

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

Kimya

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.

İnsan Embriyonik Kök Hücreleri Manyetik Rezonans Görüntüleme için in vitro Etiketleme

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

Biyoloji

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.

Kullanarak İzleme Dendritik Hücre Göç<sup&gt; 19</sup&gt; F /<sup&gt; 1</sup&gt; H Manyetik Rezonans Görüntüleme

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

İmmünoloji ve Enfeksiyon

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.

Küçük Moleküler CLT1 Peptide Hedefli Kontrast Agent ile Prostat Kanseri MR Moleküler Görüntüleme

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

Tıp

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.

Modlu Moleküler Görüntüleme Uygulamaları için Biofunctionalized Prusya Mavisi Nanopartikülleri

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.

Hücre Takip için vivo 19 F MRG

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>Murin Glioblastomunda Görüntü Kılavuzluğunda Tedavi Uygulaması için Demir Oksit Nanopartikülleri

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>Yazar Spotlight: Glioblastoma Tedavisi için Demir Oksit Nanopartikülleri ile Yenilikçi Kanser Tedavileri

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.

Bir Glioblastoma Multiforme Hayvan Modelinde Bir Oligonükleotid Yükünün Nanopartikül Teslimi

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 ...

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Teşhis ve Tedavi İzleme Nanomalzemelerin Kayıtlı bio

Sentez, Hücresel Teslimat ve

İnsan Embriyonik Kök Hücreleri Manyetik Rezonans Görüntüleme için in vitro Etiketleme

Kullanarak İzleme Dendritik Hücre Göç

Küçük Moleküler CLT1 Peptide Hedefli Kontrast Agent ile Prostat Kanseri MR Moleküler Görüntüleme

Modlu Moleküler Görüntüleme Uygulamaları için Biofunctionalized Prusya Mavisi Nanopartikülleri

Hücre Takip için vivo ¹⁹ F MRG

Bir Glioblastoma Multiforme Hayvan Modelinde Bir Oligonükleotid Yükünün Nanopartikül Teslimi

Bir Glioblastoma Multiforme Hayvan Modelinde Bir Oligonükleotid Yükünün Nanopartikül Teslimi

Bir Glioblastoma Multiforme Hayvan Modelinde Bir Oligonükleotid Yükünün Nanopartikül Teslimi