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.

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The authors have nothing to disclose.

덴드리머 MRI 조영제의 제조 모노머 유닛의 적절한 선택을 요구한다 (즉, 하나님에 대한 킬 레이터 (III)). 그들은이 상자성 이온의 독성을 감소시키고, 현재까지 비 환식의 다양한 및 거대 고리 킬 레이터는 이러한 목적으로 제공 1-3. 이들 중, 거대 고리 형 DOTA 킬레이트는 높은 열역학적 안정성 및 불활성 운동을 보유하고, 따라서, 불활성 MRI 조영제 1,18의 제조에 가장 바람직?...

자기 공명 영상 (MRI)은 인해 비침 특성이 우수한 고유 연조직 콘트라스트 널리 생물 의학 연구 및 임상 진단에 사용하는 강력한 비 이온화 이미징 기술이다. 가장 일반적으로 사용되는 MRI 방법은 수분 신호의 밀도의 차이에 기초하여, 조직 내에서 고해상도 이미지 및 상세 정보의 제공 물 양자로부터 얻어지는 신호를 이용한다. 신호 강도 및 MRI 실험의 특이성은 또한 조영제 (CAS)를 사용하여 개선 될 수있다. 이러한 상자성 또는 초상 자성 길이 (T 1)와 횡 방향에 영향을 종 (T 2) 완화 시간은 각각 1,2이다. 폴리 카르 복실 산 리간드 란탄 족 이온의 가돌리늄 착물은 가장 일반적으로 사용되는 하나의 CA T이다. 가돌리늄 (III)는 T 1 휴식을 단축물 양성자의 시간, 따라서 MRI 실험 3에서의 신호의 콘트라스트를 증가시킨다. 그러나, 이온 성 가돌리늄은 독성; 크기는 (II) 칼슘의 근사하고 심각 칼슘 보조 세포에서 신호에 영향을줍니다. 따라서, 비 환상 및 마크로 킬레이트이 독성을 중화시키기 위해 사용된다. 다양한 여러 자리 리간드는 높은 열역학적 안정성 운동 불활성 1 가돌리늄 (III) 착체의 결과, 지금까지 개발되어왔다. 특히 그 테트라 파생 DOTA (1,4,7,10-tetraazacyclododecane-1,4,7,10-테트라)에서 12 원 azamacrocycle cyclen에 따라 사람들은,이 CA 클래스의 대부분의 연구와 적용 단지입니다. 그럼에도 GdDOTA 형 CA는 낮은 콘트라스트 효율과 빠른 신장 배출 특정 단점을 표시 저분자 시스템이다. 고분자와 다가 CA는 이러한 문제 4에 좋은 해결책이 될 수 있습니다. CA의 biodistribu 이후기 주로 자신의 크기에 의해 결정되고, 고분자 CA는 조직 내에서 더 이상 유지 시간을 표시합니다. 마찬가지로 중요한 것은, 실질적으로 획득 된 MR 신호 및 측정 품질을 향상시키는 단량체 MR 프로브 (예 GdDOTA 착체)의 증가 된 국소 농도 이러한 에이전트 결과 multivalency. 덴드리머는 MRI 4,5에 대한 다가 CA의 준비를위한 가장 바람직한 발판 사이에 있습니다. 잘 정의 된 크기의이 매우 분기 거대 분자는 표면에 다양한 커플 링 반응하는 경향이 있습니다. 이 작품에서 우리는 한 세대 4 (G4) 폴리 (아미도 아민) GdDOTA 같은 킬레이트 (DCA)에 결합 (PAMAM) 덴드리머로 구성된 MRI에 대한 덴드리머 CA의 제조, 정제 및 특성을보고합니다. 우리는 반응성 DOTA 유도체의 합성 및 PAMAM 덴드리머과의 커플 링을 설명합니다. 하나님 (III), 표준 물리 화학적 특성과 착화시 proceduDCA 재 수행 하였다. 마지막으로, MRI 실험 저분자 CA에 의한 것보다 더 강한 콘트라스트 MR 화상을 생성하기 DCA의 능력을 입증 하였다.

<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

비 고리 또는 마크로 킬레이트와 가돌리늄 (III) 상자성의 착물은 자기 공명 영상 (MRI)에 대한 가장 일반적으로 사용되는 조영제 (CAS)이다. 그들의 목적 따라서 MR 화상 콘트라스트 및 MRI 측정의 특이성을 증가 조직 물의 양자의 이완 율을 향상시킬 수있다. 현재 임상 적으로 승인 된 조영제 빠르게 본체로부터 클리어 저 분자량 분자이다. 상자성 킬레이트 제의 담체로서 덴드리머의 사용이 더 효율적인 MRI 조영제의 미래 개발에 중요한 역할을 할 수있다. 특히, 높은 신호 대비 상자성 종 결과의 국소 농도의 증가. 또한,이 CA는 고 분자량과 크기 때문에 장기간 조직 체류 시간을 제공한다. 여기서는 폴리 (아미도 아민)에 기초한 고분자 MRI 조영제 (PAMAM) monomacro 함께 덴드리머를 제조하기위한 편리한 방법을 보여순환 DOTA 형 킬레이트 (DOTA - 1,4,7,10-tetraazacyclododecane-1,4,7,10-테트라). 킬레이트 부 티오 브리지를 형성 PAMAM 덴드리머의 아민 표면기를 향해 이소 티오 시아 네이트 (NCS) 기의 반응성을 이용하여 추가 하였다. 덴드리머 제품 그래피, 핵 자기 공명 스펙트럼, 질량 분석, 및 원소 분석에 의해 분석 하였다. 마지막으로, 고해상도 자기 공명 영상을 기록하고, 제조 된 덴드리머와 시판 제제 단량체로부터 얻어지는 신호 대조와 비교 하였다.

DCA의 제조는 두 단계로 구성되었다 : 1) 단량체 DOTA 형 킬레이트의 합성 (도 1)과 G4의 PAMAM 덴드리머와 복잡 덴드리머 하나님 (III)의 후속 제조와 킬레이트 2) 커플 링 (도 2) . 첫 번째 단계에서, 네 카복실산 함유 cyclen 기반 DOTA 형 킬레이트 및 상기 합성 변형 적합한 직교 그룹을 제조 하였다. 부틸 2- 브로 모 -4- (4- 니트로 페닐) 부?...

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

이 프로토콜은 상자성 가돌리늄 이온을 배위 cyclen 계 마크로 킬레이트를 운반하는 덴드리머 자기 공명 영상 (MRI) 조영제의 제조 및 특성을 설명한다. 시판되는 모노머 아날로그에 비해 시험 관내 MRI의 일련의 실험에서이 에이전트는 MRI 증폭 신호를 생성했다.

준비 및<em&gt; 체외</em&gt; 자기 공명 영상에 대한 덴드리머 기반 대조 대리인의 특성

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

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JoVE Journal

Chemistry

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

9.8K 조회수.  Max Planck Institute for Biological Cybernetics.  이 프로토콜은 상자성 가돌리늄 이온을 배위 cyclen 계 마크로 킬레이트를 운반하는 덴드리머 자기 공명 영상 (MRI) 조영제의 제조 및 특성을 설명한다. 시판되는 모노머 아날로그에 비해 시험 관내 MRI의 일련의 실험에서이 에이전트는 MRI 증폭 신호를 생성했다. 

비디오: 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.

Registered Bioimaging of Nanomaterials for Diagnostic and Therapeutic Monitoring

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.

진단 및 치료 모니터링을위한 Nanomaterials 등록 Bioimaging

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

연구

생체공학

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.

합성, 세포 전달 및<em&gt; 생체 내</em&gt; 덴드리머 기반 pH 센서의 응용 프로그램

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

화학

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.

자기 공명 영상을위한 인간 배아 줄기 세포의 체외 라벨에

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

생물학

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.

사용 모니터링 수지상 세포 이동<sup&gt; 19</sup&gt; F /<sup&gt; 1</sup&gt; H 자기 공명 영상

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

면역학 및 감염병학

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.

작은 분자 CLT1 펩타이드 표적 조영제와 전립선 암의 MR 분자 영상

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

의학

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.

멀티 모달 분자 이미징 애플리케이션을위한 Biofunctionalized 프 러시안 블루 나노 입자

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.

세포 추적을위한 생체 19 F MRI에서

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>쥐 교모세포종에서 영상 유도 치료 전달을 위한 산화철 나노입자

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>저자 스포트라이트: 교모세포종 치료를 위한 산화철 나노입자를 사용한 혁신적인 암 치료법

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.

Glioblastoma multiforme animal model에서 oligonucleotide payload의 나노입자 전달

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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진단 및 치료 모니터링을위한 Nanomaterials 등록 Bioimaging

합성, 세포 전달 및

자기 공명 영상을위한 인간 배아 줄기 세포의 체외 라벨에

사용 모니터링 수지상 세포 이동

작은 분자 CLT1 펩타이드 표적 조영제와 전립선 암의 MR 분자 영상

멀티 모달 분자 이미징 애플리케이션을위한 Biofunctionalized 프 러시안 블루 나노 입자

세포 추적을위한 생체 ¹⁹ F MRI에서

Glioblastoma multiforme animal model에서 oligonucleotide payload의 나노입자 전달

Glioblastoma multiforme animal model에서 oligonucleotide payload의 나노입자 전달

Glioblastoma multiforme animal model에서 oligonucleotide payload의 나노입자 전달