The authors wish to acknowledge funding from the European Regional Development Fund &#8211; FNUSA-ICRC (no. CZ.1.05/ 1.1.00/ 02.0123), the American Heart Association Scientist Development Grant (AHA #06-35185N), and the National Institutes of Health (NIH #T32HL007111).

マグネタイトゲルの合成1。 <ol><li>エチルアルコールが続く脱イオン水、続いて濃塩酸を使用して、すべてのガラス器具を洗ってください。好ましくは乾燥炉中で、O / Nを乾燥することができます。 注意！塩酸は危険です - ドラフト内で個人用保護具や作業を着用。エチルアルコールは有害である - 個人用保護具を着用します。 </li><li>脱ガス、脱イオンH 2 Oを 500ミリリットルを静かに30分間N 2ガ ​​スをバブリングすることによりDreschelボトルを使用してください。 </li><li>セットアップマグネタイト合成装置を化学ヒュームフード内。 <ol><li> isomantleヒーター内500mlの三口丸底フラスコを置き、クランプを使用して、中央の口を確保し、スタンド。 </li><li>丸底フラスコの側面口の1つ、残りの側の首にゴム隔壁を還流冷却器にゴム隔膜を取り付けます。連続還流冷却器を通して冷たい水を実行します。 </li><li>パンク番目N 2ガ ​​スラインに接続された針を用いて電子丸底フラスコのゴム隔壁とガス流出を可視化するためにバブラー（水とのすなわち、フラスコ）に実行されているガスラインに接続された針で還流冷却器のゴム隔膜を穿刺。 </li><li>パドルアダプタを介して丸底フラスコの中央の口にブレードパドルを取り付けます。スタンドに取り付けられたオーバーヘッドスターラーをブレードパドルのシャフトを取り付けます。 </li></ol></li><li> N 2ガ ​​スを用いた丸底フラスコをパージし、低いが検出速度で流れるN 2ガ ​​スを残します。 </li><li>丸底フラスコから還流冷却器を取り外し、塩化鉄（III）、鉄の0.6125グラム（II）塩化物水和物の1.000グラムを追加し、脱気H 2 Oの50ミリリットル 注意！塩化鉄（III）および塩化鉄（II）四水和物は、有害である - 個人用保護具を着用します。 </li><li> 50に加熱しながら還流冷却器を取り付け、1000rpmで攪拌°C。これらの条件下で攪拌すると、10 nmの直径のマグネタイトナノ粒子を生成します。 </li><li>一旦、50℃で、さらに攪拌しながら丸底フラスコにゴム隔膜を介して注入することにより、28％水酸化アンモニウム溶液10mlを加えます。 注意！水酸化アンモニウムは有害である - 個人用保護具を着用します。 注：水酸化アンモニウム溶液は、マグネタイトを沈殿させるために使用され、溶液が黒くなるべきです。 </li><li>まだ攪拌しながらアンモニアガスを沸騰する90℃に丸底フラスコと熱からゴム隔壁および N 2ガ ​​スラインを外します。 注：これは、還流冷却器のゴム隔壁を穿刺することにより、丸底フラスコに、N 2の流れを維持するために、任意である、しかし、マグヘマイトへの磁鉄鉱 ​​の酸化は、このステップの間に無視できるものです。 </li><li>いったん90℃でまだ攪拌しながら、丸底フラスコにオレイン酸の1ミリリットルを追加します。オレイン酸は、マグネタイトNA被覆するために使用されていますマグネタイトのゲルを形成するnoparticles。 注意！オレイン酸は有害である - 個人用保護具を着用します。 </li><li>丸底フラスコにゴム隔壁および N 2ガ ​​スラインを交換し、還流冷却器を取り外します。 </li><li>熱をオフにして、2時間、500rpmで攪拌​​します。 </li><li> isomantleヒーターからの丸底フラスコを取り外し、マグネタイトゲルを保持するために、フラスコの底に対して保持強力な磁石を使用している間、残りの液体をデカント。 注意！損傷または傷害を避けるために、細心の注意を持つ強力な磁石を処理します。 </li><li>空気乾燥O / N（オプション）にマグネタイトゲルを許可します。 </li></ol>マグネタイトゲルの2精製<ol><li>マグネタイトゲルを溶解させた丸底フラスコに、ヘキサン40 mlを加え 注意！ヘキサンは有害である - ドラフト内で個人用保護具と仕事を着用してください。 </li><li>残留H 2 Oあちこち除去するために、脱気の H 2 O 40mLで分液漏斗を使用してくださいマグネタイト溶液メートル。 <ol><li>ゆっくりと分液漏斗内のH 2 Oにマグネタイト液を注ぎ、軽く5分間二相液体を旋回。 </li><li>外排出し、下部の水部分を破棄します。 </li><li>ゆっくりマグネタイトソリューションの下に、それが落ち着くように、分液漏斗に脱気したH 2 Oの40ミリリットルを加え、穏やかに旋回し、以前のようにドレイン。 </li><li>三度目の洗浄するために繰り返します。 </li></ol></li><li> 、三角フラスコにマグネタイト液を移し、無水硫酸ナトリウムの価値はいくつかへらを追加し、マグネタイト溶液から、残りの残留H 2 Oを除去するための渦。 </li><li>硫酸ナトリウム及び残留H 2 Oを除去するための濾過漏斗で1ミクロンの濾紙マグネタイト溶液を濾過 注：真空支援が推奨されます。 </li><li> 50ミリリットル蒸発フラスコにマグネタイト液を移し、ヘキサンを蒸発させるために、ロータリーエバポレーターを使用以下の条件で2時間：中程度の回転速度、真空度は50℃の水浴でフラスコを蒸発させ、塗布し、24℃の水が凝縮器を循環します。 注：必要に応じて、PLGAでコーティングする前にマグネタイトゲルを保存します。 </li></ol> PLGAシェルを使用したマグネタイトナノ粒子の3コーティング<ol><li> 1.5％（M / V）のソリューションを作成するために、酢酸エチル240mlの中のPLGAの3.60グラム（75/25ブレンド）を溶解します。注意：酢酸エチルは有害である - ドラフト内で個人用保護具と仕事を着用してください。 </li><li> 5.0％（M / V）溶液を作成するために、磁気スターラーを用いて脱気H 2 O 500ml中のPluronic F-127の25.00グラムを溶解します。 注：プルロニックF-127は、生体適合性界面活性剤として作用する非イオン性両親媒性ブロック共重合体です。なお、ステップ3.3.2で水中油型エマルジョンを安定化するのに役立ちます。 </li><li>ミクロを使用して、重み付けされたガラスバイアル内で6 0.040グラムのアリコートにマグネタイトゲルを収集します。 PERF各アリコートについては、以下のコーティング及び洗浄工程をORM。 注：一定分量は、ステップ4で劣化する前に凍結乾燥を最小限に抑えながら、純度と収率を最大れる、効率的な処理および磁気デカンテーションを確保するために必要です。 <ol><li> 10分間超音波洗浄器で0.040グラムのマグネタイトゲルのアリコートおよびプラスチックビーカー超音波処理にPLGA溶液の40ミリリットルを追加します。 </li><li>プラスチックビーカーのプルロニック溶液80 mlを加え、すぐに水中油型エマルジョンとしてマグネタイトナノ粒子上のPLGAコーティングを形成するために7分間最高設定で実験室用ミキサーで乳化します。 </li><li>すぐに酢酸エチルを蒸発させ、化学換気フード中で1時間脱イオンH 2 O及び超音波処理を1 LにSPION溶液を希釈します。 </li><li> SPION溶液に次の強力な磁石を置き、静かに磁石で茶色がかっSPIONsを収集するためにかき混ぜます。 注：これは、断続的に、数時間攪拌する必要があるかもしれません溶液前SはSPIONsのほとんどが収集されたことを示す白っぽくなります。 </li><li>磁石をビーカーにSPIONsを維持しながら水溶液をデカント。 </li><li>次のようにSPIONsを3回洗浄します。 <ol><li>脱イオンH 2 O 1LにSPIONsサスペンド</li><li> 20分間SPION液を超音波処理。 </li><li> SPION溶液に次の強力な磁石を置き、静かに磁石で茶色がかっSPIONsを収集するためにかき混ぜます。これは、溶液がSPIONsの大部分が回収されたことを示す明確なターン前に断続的に数時間撹拌することが必要であり得ます。 </li><li>磁石をビーカーにSPIONsを維持しながら水溶液をデカント。 </li></ol></li></ol></li><li>水性懸濁液のような単一の加重ガラス瓶に6マグネタイトゲルアリコートのそれぞれから合成SPIONsを収集します。必要に応じて、必要に応じて磁気的に余分な水分をデカント。 </li></ol> 4.フリーズSPIONsの-drying <ol><li> SPIONソリューションをフリーズします。 </li><li>凍結乾燥した凍結乾燥機でSPION液O / Nに。 </li><li>凍結乾燥SPIONsを計量。細胞標識に使用するまで凍結乾燥SPIONsを-20℃で保存することができます。 注：-20°C劇的での保存は、分解速度を減少させ、貯蔵寿命を向上させます。 </li></ol> SPIONsによる細胞の5ラベリング<ol><li> 40 mg / mlの濃度でリン酸緩衝生理食塩水（PBS）中SPIONsのアリコートを一時停止し、30分間超音波処理します。 </li><li>細胞培養培地を5μl/ mlの濃度で細胞のほぼコンフルエントなフラスコにSPION溶液を加えます。静かにフラスコを揺動することにより均一な分布を確認してください。 </li><li> 37℃で16時間細胞をインキュベートします。 </li><li>穏やかに培地を吸引し、PBSで細胞を2回洗浄します。 </li><li>磁気標識細胞を収集し、実験に使用します。 </li><li>未使用SPION溶液は​​4℃で保存することができ、米国でなければなりません数ヶ月以内にエド。各使用前に30分間超音波処理。 </li></ol>

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V., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Magnetically+targeted+endothelial+cell+localization+in+stented+vessels.">Magnetically targeted endothelial cell localization in stented vessels.</a> J Am Coll Cardiol. 48 (9), 1839-1845 (2006).</li><li>Pislaru, S. V., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Magnetic+forces+enable+rapid+endothelialization+of+synthetic+vascular+grafts.">Magnetic forces enable rapid endothelialization of synthetic vascular grafts.</a> Circulation. 114 (1 Suppl), 314-318 (2006).</li><li>Wang, Y. X., Xuan, S., Port, M., Idee, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recent+advances+in+superparamagnetic+iron+oxide+nanoparticles+for+cellular+imaging+and+targeted+therapy+research.">Recent advances in superparamagnetic iron oxide nanoparticles for cellular imaging and targeted therapy research.</a> Curr Pharm Des. 19 (37), 6575-6593 (2013).</li><li>Yellen, B. B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Targeted+drug+delivery+to+magnetic+implants+for+therapeutic+applications.">Targeted drug delivery to magnetic implants for therapeutic applications.</a> J Magn Magn Mater. 293 (1), 647-654 (2005).</li><li>Granot, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Clinically+viable+magnetic+poly(lactide-co-glycolide)+particles+for+MRI-based+cell+tracking.">Clinically viable magnetic poly(lactide-co-glycolide) particles for MRI-based cell tracking.</a> Magn Reson Med. , (2013).</li><li>Levy, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Long+term+in+vivo+biotransformation+of+iron+oxide+nanoparticles.">Long term in vivo biotransformation of iron oxide nanoparticles.</a> Biomaterials. 32 (16), 3988-3999 (2011).</li><li>Mirshafiee, V., Mahmoudi, M., Lou, K., Cheng, J., Kraft, M. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Protein+corona+significantly+reduces+active+targeting+yield.">Protein corona significantly reduces active targeting yield.</a> Chem Commun (Camb). 49 (25), 2557-2559 (2013).</li><li>Salvati, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transferrin-functionalized+nanoparticles+lose+their+targeting+capabilities+when+a+biomolecule+corona+adsorbs+on+the+surface.">Transferrin-functionalized nanoparticles lose their targeting capabilities when a biomolecule corona adsorbs on the surface.</a> Nat Nanotechnol. 8 (2), 137-143 (2013).</li><li>Landazuri, N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Magnetic+targeting+of+human+mesenchymal+stem+cells+with+internalized+superparamagnetic+iron+oxide+nanoparticles.">Magnetic targeting of human mesenchymal stem cells with internalized superparamagnetic iron oxide nanoparticles.</a> Small. 9 (23), 4017-4026 (2013).</li><li>Sun, J. H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vitro+labeling+of+endothelial+progenitor+cells+isolated+from+peripheral+blood+with+superparamagnetic+iron+oxide+nanoparticles.">In vitro labeling of endothelial progenitor cells isolated from peripheral blood with superparamagnetic iron oxide nanoparticles.</a> Mol Med Rep. 6 (2), 282-286 (2012).</li><li>Zhang, B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Detection+of+viability+of+transplanted+beta+cells+labeled+with+a+novel+contrast+agent+-+polyvinylpyrrolidone-coated+superparamagnetic+iron+oxide+nanoparticles+by+magnetic+resonance+imaging.">Detection of viability of transplanted beta cells labeled with a novel contrast agent - polyvinylpyrrolidone-coated superparamagnetic iron oxide nanoparticles by magnetic resonance imaging.</a> Contrast Media Mol Imaging. 7 (1), 35-44 (2012).</li><li>Song, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Labeling+efficacy+of+superparamagnetic+iron+oxide+nanoparticles+to+human+neural+stem+cells:+comparison+of+ferumoxides,+monocrystalline+iron+oxide,+cross-linked+iron+oxide+(CLIO)-NH2+and+tat-CLIO.">Labeling efficacy of superparamagnetic iron oxide nanoparticles to human neural stem cells: comparison of ferumoxides, monocrystalline iron oxide, cross-linked iron oxide (CLIO)-NH2 and tat-CLIO.</a> Korean J Radiol. 8 (5), 365-371 (2007).</li></ol>

The authors declare that they have no competing financial interests.

任意のナノ粒子合成プロトコルと同様に、反応物質の化学物質の純度は、最小限の細胞毒性効果を持つことになり、高品質のSPIONsを達成するために重要です。これは、オレイン酸（≥99％）、塩化鉄（II）四水和物（≥99.99％）、塩化鉄（III）（≥99.99％）、酢酸エチルなどの非常に純粋な試薬を購入することが重要である（HPLCグレード、≥99.9％ ）、ヘキサン（HPLCグレード、≥97.0％）、水酸化アンモニウム（≥99.99％）、及び硫酸ナトリウム（≥99.0％）。これは、比較的高価であり、非常に純粋な、高品質のPLGAを、購入するために特に重要です。また、すべてのガラス製品は、完全に塩酸、脱イオン水、エチルアルコールで洗浄し、使用前に乾燥させなければなりません。 同様に、プロトコル内の精製工程および洗浄工程は、最終的なSPIONsが高品質であること、最小限の細胞毒性作用を持つことになります確保するために重要です。マグネタイトゲルはあってはなりませんPLGAで被覆する前に可能な限り多くの水酸化アンモニウム、水、及びヘキサン等。したがって、プロトコルの多くはマグネタイトゲルの純度を確保することに専念しています。その後、PLGA-マグネタイトSPIONsは、酢酸エチル、プルロニック、過剰PLGAの自由でなければなりません。最終SPIONの洗浄工程は、プロトコルの中で最も時間のかかる部分ですが、高純度を確保するために完了する必要があります。具体的には、各洗浄工程の間に粒子の磁気回収は非常に時間がかかる可能性があります。溶液を攪拌して大幅に粒子収集の速度を上げることができるが、磁気攪拌棒を使用することができません。低速で動作するオーバーヘッド攪拌機は、急速な粒子収集のための最も有効な手段です。確認SPIONsの大きな茶色がかったコレクションが磁石に表示され、その溶液をデカント前に白またはクリア表示されます。これは多くの場合、攪拌の数時間を必要とすることができますが、より高い最終収量になります。磁気デカンテーションステップはまた、唯一のMAGNを確保するのに役立ちますすべての非磁性材料が廃棄されている間エティックな粒子が保持されます。 過剰な鉄レベルは、細胞傷害性であることができるので、この技術を用いて細胞に付与することができる磁気質量の量が制限されます。鉄の濃度は、特に敏感な細胞型で減少または特に弱い磁場で増加する必要があるかもしれませんが、ここで説明されたプロトコルは、安全性と有効性のバランスをとるための実証済みの出発点を提供します。このプロトコルによって合成SPIONsはPLGAのマグネタイトの質量比が1時15分を有する溶液から作られ、SPIONsは、細胞培養培地に200μg/ mlの濃度で細胞に導入されます。これらのパラメータのいずれかが必要に応じて、各細胞によってエンドサイトーシス、鉄の量を変化させるように調整することができます。 SPIONsは、人間の移植のための安全であり、時間（約40〜50日の半減期）31の上に生分解されます。マグネタイトおよびPLGAの両方が無害degradを形成エーションの製品とは、自然の経路32を介して体内から消去されます。 SPIONsの生分解性の性質は、任意の細胞毒性効果は時間とともに減少することを意味するだけでなく、数ヶ月を超えて、その磁気特性を維持するために、細胞を必要としないものへの潜在的なアプリケーションを制限します。 SPIONsはまた、細胞を標識し、表面タンパク質を必要とせず、その磁気効果を付与も生物学的環境33,34に暴露されると、タンパク質のコロナの形成を受けやすいリガンドを標的にするという利点を有します。 細胞に磁気特性を付与することは、標的細胞の配信を必要とするか、29をソートする生物医学的用途の幅広いするのに便利です。種々の細胞型が安全に間葉系幹細胞35、内皮前駆細胞36、β島細胞37、及び神経幹細胞38を含むSPIONsをエンドサイトーシスする能力を実証しました。磁気CEL配信条件の制御の高度が必要である場合、Lは、標的化技術を標的とする他​​の細胞よりも好ましいです。

Targeted delivery and capture of cells to specific sites within the body is desirable for a variety of biomedical applications. Delivery of neural stem cells to the brain by MRI-guided focused ultrasound has been proposed as a possible treatment option for neurodegenerative disease, traumatic brain injury, and stroke1. Mesenchymal stem cells are being studied for their ability to deliver anti-cancer drugs to tumors due to their natural tumor-tropic properties2,3. Cardiac stem cells have been delivered to the heart as a possible treatment for myocardial infarction4,5. Vascular stents have been developed with CD34 antibodies to capture circulating progenitor cells6. While promising, these cell targeting approaches present drawbacks including lack of cell specificity, inconsistent cell retention, and off-target cell delivery.
The overall goal of the current method is to enable magnetically directed targeting of cells for a variety of cell delivery and sorting applications. Magnetic targeting allows for controlled delivery of specific cells to a specific target site with minimal off-target effects7. The magnetic fields can be generated by implanted or external devices to safely direct the movement of magnetically-labeled cells within the body8. Numerous research efforts have focused on magnetically directed targeting of stem cells to injured tissues such as the heart9-14, retina15, lung16, skin17, spinal cord18,19, bone20, liver21, and muscle22,23 in order to improve regeneration outcomes.
Magnetic targeting of cells has also been studied extensively as a means to endothelialize implantable cardiovascular devices. A uniform and complete endothelium provides a barrier between the device and circulating blood elements to mitigate thrombosis and inflammation. Endothelial cells can be delivered to the device either prior to implantation or via the vascular system following implantation. In both cases, magnetic fields are used to capture cells to the surface of the device and retain the cells when subjected to the shear stress generated by circulating blood. Magnetic vascular stents24-27 and vascular grafts28 have both been fabricated and tested for this purpose.
Magnetic cell targeting requires a strategy for labeling cells with magnetic carrier particles. These particles can be bound to the surface of cells via antibodies or ligand/receptor pairs or they can be endocytosed into the cells. Superparamagnetic iron oxide nanoparticles (SPION) are biodegradable, biocompatible, and readily endocytosed by a variety of cell types29. These particles effectively render a cell responsive to magnetic fields and are naturally degraded over time. SPIONs provide a straightforward and safe means of magnetically labeling cells in culture for a variety of magnetic targeting and sorting applications. A method for synthesizing SPIONs with a magnetite (Fe3O4) core and poly(lactic-co-glycolic acid) (PLGA) shell is provided. In addition, a method for labeling cells in culture with SPIONs is provided.

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr>
			<td>Ammonium Hydroxide solution, 28% NH3 in H2O, &#8805;99.99% trace metal basis</td>
			<td>Sigma-Aldrich</td>
			<td>338818-100ML&#160;</td>
			<td>Harmful reagent - wear personal protective equipment</td>
		</tr>
		<tr>
			<td>Dreschel bottle, 500 mL</td>
			<td>Ace Glass</td>
			<td>5516-16</td>
			<td></td>
		</tr>
		<tr>
			<td>Ethyl Acetate, CHROMASOLVR Plus, for HPLC, 99.9%&#160;</td>
			<td>Sigma-Aldrich</td>
			<td>650528-1L</td>
			<td>Harmful reagent - wear personal protective equipment &#38; work in fume hood</td>
		</tr>
		<tr>
			<td>Ethyl alcohol</td>
			<td>Sigma-Aldrich</td>
			<td>E7023</td>
			<td>Harmful reagent - wear personal protective equipment</td>
		</tr>
		<tr>
			<td>Filter paper, 3 cm dia, grade 1</td>
			<td>Fisher</td>
			<td>09-805P</td>
			<td>For use with glass filter funnel</td>
		</tr>
		<tr>
			<td>Glass beakers, 1 L</td>
			<td>Fisher</td>
			<td>FB-101-1000</td>
			<td>For washing SPIONs</td>
		</tr>
		<tr>
			<td>Glass filter funnel, vacuum hose adapter, fits 24/40, 30 mL</td>
			<td>Fisher</td>
			<td>K954100-0344&#160;</td>
			<td></td>
		</tr>
		<tr>
			<td>Glass vial caps</td>
			<td>Fisher</td>
			<td>03-391-46</td>
			<td>For use with glass vials</td>
		</tr>
		<tr>
			<td>Glass vials, 2 mL</td>
			<td>Fisher</td>
			<td>03-391-44</td>
			<td>For collecting magnetite gel &#38; SPIONs</td>
		</tr>
		<tr>
			<td>Hexane, CHROMASOLVR, for HPLC, &#8805;97.0% (GC)</td>
			<td>Sigma-Aldrich</td>
			<td>34859-1L&#160;</td>
			<td>Harmful reagent - wear personal protective equipment &#38; work in fume hood</td>
		</tr>
		<tr>
			<td>Hydrochloric acid</td>
			<td>Sigma-Aldrich</td>
			<td>H1758</td>
			<td>Harmful reagent - wear personal protective equipment &#38; work in fume hood</td>
		</tr>
		<tr>
			<td>Iron(II) chloride tetrahydrate, &#8805;99.99% trace metals basis&#160;</td>
			<td>Sigma-Aldrich</td>
			<td>380024-5G</td>
			<td>Harmful reagent - wear personal protective equipment</td>
		</tr>
		<tr>
			<td>Iron(III) chloride anhydrous, powder, &#8805;99.99% trace metals basis</td>
			<td>Sigma-Aldrich</td>
			<td>451649-1G</td>
			<td>Harmful reagent - wear personal protective equipment</td>
		</tr>
		<tr>
			<td>Isomantle heater, 500 mL</td>
			<td>Voight Global</td>
			<td>EM0500/CEX1</td>
			<td></td>
		</tr>
		<tr>
			<td>Laboratory mixer</td>
			<td>Silverson</td>
			<td>L5M-A</td>
			<td></td>
		</tr>
		<tr>
			<td>Lyophilizer</td>
			<td>Labconco</td>
			<td>7670520</td>
			<td></td>
		</tr>
		<tr>
			<td>Microspatulas</td>
			<td>Fisher</td>
			<td>21-401-25A</td>
			<td>For transfering magnetite gel</td>
		</tr>
		<tr>
			<td>NdFeB magnet, 1 in x 1 in x 1 in</td>
			<td>Amazing Magnets</td>
			<td>C1000H-M</td>
			<td>Very strong magnet, handle with care</td>
		</tr>
		<tr>
			<td>Oleic acid, &#8805;99% (GC)</td>
			<td>Sigma-Aldrich</td>
			<td>O1008-5G&#160;</td>
			<td>Store in freezer; Harmful reagent - wear personal protective equipment</td>
		</tr>
		<tr>
			<td>Overhead stirrer</td>
			<td>IKA</td>
			<td>2572201</td>
			<td></td>
		</tr>
		<tr>
			<td>Overhead stirrer clamp</td>
			<td>IKA</td>
			<td>2664000</td>
			<td>For use with overhead stirrer</td>
		</tr>
		<tr>
			<td>Overhead stirrer H-stand</td>
			<td>IKA</td>
			<td>1412000</td>
			<td>For use with overhead stirrer</td>
		</tr>
		<tr>
			<td>Phosphate buffered saline</td>
			<td>Life Technologies</td>
			<td>10010-023</td>
			<td></td>
		</tr>
		<tr>
			<td>Plastic beakers, 250 mL</td>
			<td>Fisher</td>
			<td>02-591-28</td>
			<td></td>
		</tr>
		<tr>
			<td>PLGA PURASORB PDLG (75/25 blend)</td>
			<td>Purac</td>
			<td>PDLG 7502</td>
			<td>PDLG 7502A may be used as well; Store in freezer</td>
		</tr>
		<tr>
			<td>Pluronic F-127 powder, BioReagent, suitable for cell culture</td>
			<td>Sigma-Aldrich</td>
			<td>P2443-250G&#160;</td>
			<td></td>
		</tr>
		<tr>
			<td>PTFE expandable blade paddle, 8 mm dia</td>
			<td>SciQuip</td>
			<td>SP4018</td>
			<td></td>
		</tr>
		<tr>
			<td>PTFE vessel adapter, fits 24/40, 8 mm dia paddle</td>
			<td>Monmouth Scientific</td>
			<td>PTFE Vessel Adaptor A480</td>
			<td>For use with PTFE expandable blade paddle</td>
		</tr>
		<tr>
			<td>Recirculating chiller</td>
			<td>Clarkson</td>
			<td>696613</td>
			<td>For use with rotoevaporator</td>
		</tr>
		<tr>
			<td>Reflux condenser, fits 24/40, 250 mm</td>
			<td>Ace Glass</td>
			<td>5997-133</td>
			<td></td>
		</tr>
		<tr>
			<td>Rotoevaporator</td>
			<td>Clarkson</td>
			<td>216949</td>
			<td></td>
		</tr>
		<tr>
			<td>Round bottom flask, 50 mL, 24/40 joint</td>
			<td>Sigma-Aldrich</td>
			<td>Z414484</td>
			<td>For use with rotoevaporator</td>
		</tr>
		<tr>
			<td>Rubber septa, fits 24/40</td>
			<td>Ace Glass</td>
			<td>9096-56</td>
			<td></td>
		</tr>
		<tr>
			<td>Separatory funnel with stopper, 250 mL</td>
			<td>Fisher</td>
			<td>10-438E</td>
			<td></td>
		</tr>
		<tr>
			<td>Sodium sulfate ACS reagent, &#8805;99.0%, anhydrous, granular</td>
			<td>Sigma-Aldrich</td>
			<td>239313-500G&#160;</td>
			<td></td>
		</tr>
		<tr>
			<td>Three neck round bottom flask, angled, 24/40 joints, 500 mL</td>
			<td>Ace Glass</td>
			<td>6948-16</td>
			<td></td>
		</tr>
		<tr>
			<td>Ultrasonic cleaner perforated pan</td>
			<td>Fisher</td>
			<td>15-335-20A</td>
			<td>For use with ultrasonic cleaner</td>
		</tr>
		<tr>
			<td>Ultrasonic cleaner, 2.8 L</td>
			<td>Fisher</td>
			<td>15-335-20</td>
			<td></td>
		</tr>
		<tr>
			<td>Vacuum controller</td>
			<td>Clarkson</td>
			<td>216639</td>
			<td>For use with rotoevaporator (optional)</td>
		</tr>
		<tr>
			<td>Vacuum pump</td>
			<td>Clarkson</td>
			<td>219959</td>
			<td>For use with rotoevaporator</td>
		</tr>
	</tbody>
</table>

cell labeling and targeting with superparamagnetic iron oxide nanoparticles

細胞および治療剤の標的化送達は、オフターゲット部位への悪影響を最小限に抑えながら、標的部位で治療効果を集中することにより、生物医学的用途の広い範囲に利益をもたらします。磁気細胞標的化は、効率的で、安全で、簡単な配信技術です。超常磁性酸化鉄ナノ粒子（SPION）は、生体適合性、生分解性であり、および磁界に応答してレンダリングするために細胞内に取り込ませることができます。合成プロセスは、マグネタイト鉄（Fe 3 O 4）を作成することを含む、ポリ（乳酸-コ-グリコール酸）（PLGA）コーティングを形成するために、高速乳化続いナノ粒子。 PLGA-マグネタイトSPIONsは約10 nmの直径のマグネタイトコアを含む直径約120nmです。培養培地中に置かれたとき、SPIONsは、天然細胞によってエンドサイトーシスおよび細胞質エンドソーム内の小さなクラスターとして記憶されます。これらの粒子は、細胞に十分な磁気質量を与え磁場内にターゲットを可能にします。多数の細胞選別とターゲットアプリケーションは、磁場に反応する様々な細胞型をレンダリングすることで有効になっています。 SPIONsは、同様に、腫瘍の治療または組織はんだ付けのための医療用イメージング造影剤として使用する、標的薬物や遺伝子デリバリー、診断アッセイ、およびローカル温熱療法の生成を含む他の生物医学的用途の多様性を持っています。

マグネタイトナノ粒子は、50℃、1000回転（図1）での鉄（III）、塩化鉄（II）塩化物水和物の水溶液を攪拌した結果、直径が約10nmです。これらの結果は、マグネタイトナノ粒子の合成に成功を実証します。これは、最初に合成しようとすると、バッチの少量の試料から採取したマグネタイトナノ粒子のサイズおよび形状を確認することが重要です。透過型電子顕微鏡（TEM）は、これらの粒子を可視化するための好ましい方法です。バッチは破棄されるべきであり、 図1に示すように、マグネタイトナノ粒子は直径および球形で10nm程度でない場合、合成が再試行する必要があります。 120nmで（図2）の直径を有するPLGA-マグネタイトSPIONsの高速乳化剤結果を用いて、PLGAとマグネタイトナノ粒子をコーティングします。これらの結果は、成功した実証しますPLGA-マグネタイトSPIONsの合成。これは、初めて合成をしようとしたときにバッチの小さなサンプルから採取したPLGA-マグネタイトSPIONsの大きさや形状を確認することが重要です。走査型電子顕微鏡（SEM）は、これらの粒子を可視化するための好ましい方法です。バッチは廃棄されるべきであり、 図2に示すように、PLGA-マグネタイトSPIONsがより大きいまたはより小さい粒子は、特定の用途のために望ましいかもしれないが、組成が不明である。直径の球状で120nm程度でない場合、合成を再度試みるべきしたがって、細胞標識、磁化率、および細胞毒性は予測できません。 ナノ粒子のエンドサイトーシスにおける16時間の結果（図3）のためのSPIONsと血液伸長内皮細胞のインキュベーション。これらの結果は、SPIONsでの細胞の成功したラベルを示しています。それから採取された細胞内SPIONsの存在を確認することが重要です初めての標識をしようとバッチの小さなサンプル。透過型電子顕微鏡では、これらのSPION標識細胞を可視化するための好ましい方法です。細胞は廃棄すべきであり、PLGA-mangetite SPIONsは、図3に示すように、細胞質エンドソーム内で一緒にクラスタ化された黒色粒子丸として表示されない場合は、ラベルを再度試みるべきである。また、SPIONsのより低い濃度は、磁気細胞標的化を可能にするために失敗し、 SPIONsのより高い濃度は、細胞傷害性であり得ます。必要に応じて、細胞を標識するために使用されるSPIONsの濃度に応じて調整することができます。 細胞内にロードされた鉄の量は、強磁性植え込み可能な医療装置（図4）と生存細胞の磁気捕捉を達成するのに十分です。これらの結果は、成功したSPION媒介磁気細胞標的化を実証します。効果をターゲットに強力な細胞が所望される場合、好ましい戦略はincreaことです生成または印加磁界8,30の強度や勾配をSE。細胞を標識するために使用さSPIONsの濃度を増加することのみによる細胞毒性の懸念への最後の手段として試みられるべきです。改善された細胞生存率が所望される場合、細胞を標識するために使用されるSPIONsの濃度を減少させるべきです。 <img alt="図1" src="/files/ftp_upload/53099/53099fig1.jpg" /> マグネタイトナノ粒子の図1のTEM像。マグネタイトナノ粒子は、透過電子顕微鏡（TEM）によって示されるように、直径が約10nmです。粒子のサイズは球状で均一です。スケールバー= 100 nmの。 <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/53099/53099fig1large.jpg" target="_blank">この図の拡大版をご覧になるにはこちらをクリックしてください。</a> <img alt="図2" src="/files/ftp_upload/53099/53099fig2.jpg" /><br<html> PLGA-マグネタイトSPIONsの /&gt; 図2のSEM像。PLGA被覆されたマグネタイトSPIONs走査電子顕微鏡（SEM）により見られるように、直径が約120nmです。粒子のサイズは球状で均一です。スケールバー=500μmの。 <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/53099/53099fig2large.jpg" target="_blank">この図の拡大版をご覧になるにはこちらをクリックしてください。</a> <img alt="図3" src="/files/ftp_upload/53099/53099fig3.jpg" /> 磁気的に標識された内皮細胞の図3のTEM像。透過型電子顕微鏡（TEM）によって可視化し、磁気標識された血液伸長内皮細胞。 SPIONsは自然に細胞によってエンドサイトーシスおよび細胞質エンドソーム内の小さなクラスターに格納されています。左スケールバー=2μmで、右のスケールバー= 0.5ミクロン。 24から許可を得て再印刷します。/files/ftp_upload/53099/53099fig3large.jpg「ターゲット= &quot;_空白&quot;&gt;この図の拡大版をご覧になるにはこちらをクリックしてください。 <img alt="図4" src="/files/ftp_upload/53099/53099fig4.jpg" /> 磁気細胞捕獲の図4蛍光顕微鏡画像は、磁気的に標識された内皮細胞は、非磁 ​​性ステント（左）よりも有意に高い率で強磁性血管ステント（右）に引き寄せられます。スケールバー=100μmです。再印刷24からの許可を得て。 <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/53099/53099fig4large.jpg" target="_blank">この図の拡大版をご覧になるにはこちらをクリックしてください。</a>

Watch this Scientific Journal Video about Cell Labeling and Targeting with Superparamagnetic Iron Oxide Nanoparticles at JoVE.com

Cell Labeling and Targeting with Superparamagnetic Iron Oxide Nanoparticles

Targeted cell delivery is useful in a variety of biomedical applications. The goal of this protocol is to use superparamagnetic iron oxide nanoparticles (SPION) to label cells and thereby enable magnetic cell targeting approaches for a high degree of control over cell delivery and localization.

細胞標識および超常磁性酸化鉄ナノ粒子とターゲティング

Targeted delivery of cells and therapeutic agents would benefit a wide range of biomedical applications by concentrating the therapeutic effect at the ...

cell-labeling-targeting-with-superparamagnetic-iron-oxide

Nanyang Technological University

Research

JoVE Journal

Bioengineering

12.0K ビュー.  Mayo Clinic. Targeted cell delivery is useful in a variety of biomedical applications. The goal of this protocol is to use superparamagnetic iron oxide nanoparticles (SPION) to label cells and thereby enable magnetic cell targeting approaches for a high degree of control over cell delivery and localization.

ビデオ: Cell Labeling and Targeting with Superparamagnetic Iron Oxide Nanoparticles

PLGA Nanoparticles Formed by Single- or Double-emulsion with Vitamin E-TPGS

Poly(lactic-co-glycolic acid) (PLGA) is a biocompatible member of the aliphatic polyester family of biodegradable polymers. PLGA has long been a popular choice for drug delivery applications, particularly since it is already FDA-approved for use in humans in the form of resorbable sutures. Hydrophobic and hydrophilic drugs are encapsulated in PLGA particles via single- or double-emulsion. Briefly, the drug is dissolved with polymer or emulsified with polymer in an organic phase that is then emulsified with the aqueous phase. After the solvent has evaporated, particles are washed and collected via centrifugation for lyophilization and long term storage. PLGA degrades slowly via hydrolysis in aqueous environments, and encapsulated agents are released over a period of weeks to months. Although PLGA is a material that possesses many advantages for drug delivery, reproducible formation of nanoparticles can be challenging; considerable variability is introduced by the use of different equipment, reagents batch, and precise method of emulsification. Here, we describe in great detail the formation and characterization of microparticles and nanoparticles formed by single- or double-emulsion using the emulsifying agent vitamin E-TPGS. Particle morphology and size are determined with scanning electron microscopy (SEM). We provide representative SEM images for nanoparticles produced with varying emulsifier concentration, as well as examples of imaging artifacts and failed emulsifications. This protocol can be readily adapted to use alternative emulsifiers (e.g. poly(vinyl alcohol), PVA) or solvents (e.g.&#160;dichloromethane, DCM).

We describe the production and characterization of nanoparticles and microparticles composed of poly(lactic-co-glycolic acid) using vitamin E-TPGS as an emulsifier. By varying formulation parameters such as the concentration of emulsifier, it is possible to produce nanoparticles with mean diameters ranging from 220 nm to&#160;1.98 &#181;m.

Poly(lactic-co-glycolic acid) (PLGA) is a biocompatible member of the aliphatic polyester family of biodegradable polymers. PLGA has long been a popular ...

生物工学

Harmonic Nanoparticles for Regenerative Research

In this visualized experiment, protocol details are provided for in vitro labeling of human embryonic stem cells (hESC) with second harmonic generation nanoparticles (HNPs). The latter are a new family of probes recently introduced for labeling biological samples for multi-photon imaging. HNPs are capable of doubling the frequency of excitation light by the nonlinear optical process of second harmonic generation with no restriction on the excitation wavelength.
Multi-photon based methodologies for hESC differentiation into cardiac clusters (maintained as long term air-liquid cultures) are presented in detail. In particular, evidence on how to maximize the intense second harmonic (SH) emission of isolated HNPs during 3D monitoring of beating cardiac tissue in 3D is shown. The analysis of the resulting images to retrieve 3D displacement patterns is also detailed.

Protocol details are provided for in vitro labeling human embryonic stem cells with second harmonic generating nanoparticles. Methodologies for hESC investigation by multi-photon microscopy and their differentiation into cardiac clusters are also presented.

回生研究ハーモニックナノ粒子

In this visualized experiment, protocol details are provided for in vitro labeling of human embryonic stem cells (hESC) with second harmonic generation ...

Production and Targeting of Monovalent Quantum Dots

The multivalent nature of commercial quantum dots (QDs) and the difficulties associated with producing monovalent dots have limited their applications in biology, where clustering and the spatial organization of biomolecules is often the object of study. We describe here a protocol to produce monovalent quantum dots (mQDs) that can be accomplished in most biological research laboratories via a simple mixing of CdSe/ZnS core/shell QDs with phosphorothioate DNA (ptDNA) of defined length. After a single ptDNA strand has wrapped the QD, additional strands are excluded from the surface. Production of mQDs in this manner can be accomplished at small and large scale, with commercial reagents, and in minimal steps. These mQDs can be specifically directed to biological targets by hybridization to a complementary single stranded targeting DNA. We demonstrate the use of these mQDs as imaging probes by labeling SNAP-tagged Notch receptors on live mammalian cells, targeted by mQDs bearing a benzylguanine moiety.

We provide detailed instructions for the preparation of monovalent targeted quantum dots (mQDs) from phosphorothioate DNA of defined length. DNA wrapping occurs in high yield, and therefore, products do not require purification. We demonstrate the use of the SNAP tag to target mQDs to cell-surface receptors for live-cell imaging applications.

生産と一価量子ドットの標的

The multivalent nature of commercial quantum dots (QDs) and the difficulties associated with producing monovalent dots have limited their applications in ...

Fabrication of a Functionalized Magnetic Bacterial Nanocellulose with Iron Oxide Nanoparticles

In this study, bacterial nanocellulose (BNC) produced by the bacteria Gluconacetobacter xylinus is synthesized and impregnated in situ with iron oxide nanoparticles (IONP) (Fe3O4) to yield a magnetic bacterial nanocellulose (MBNC). The synthesis of MBNC is a precise and specifically designed multi-step process. Briefly, bacterial nanocellulose (BNC) pellicles are formed from preserved G. xylinus strain according to our experimental requirements of size and morphology. A solution of iron(III) chloride hexahydrate (FeCl3&#183;6H2O) and iron(II) chloride tetrahydrate (FeCl2&#183;4H2O) with a 2:1 molar ratio is prepared and diluted in deoxygenated high purity water. A BNC pellicle is then introduced in the vessel with the reactants. This mixture is stirred and heated at 80 &#176;C in a silicon oil bath and ammonium hydroxide (14%) is then added by dropping to precipitate the ferrous ions into the BNC mesh. This last step allows forming in situ magnetite nanoparticles (Fe3O4) inside the bacterial nanocellulose mesh to confer magnetic properties to BNC pellicle. A toxicological assay was used to evaluate the biocompatibility of the BNC-IONP pellicle. Polyethylene glycol (PEG) was used to cover the IONPs in order to improve their biocompatibility. Scanning electron microscopy (SEM) images showed that the IONP were located preferentially in the fibril interlacing spaces of the BNC matrix, but some of them were also found along the BNC ribbons. Magnetic force microscope measurements performed on the MBNC detected the presence magnetic domains with high and weak intensity magnetic field, confirming the magnetic nature of the MBNC pellicle. Young&#39;s modulus values obtained in this work are also in a reasonable agreement with those reported for several blood vessels in previous studies.

Here, we present a protocol to make a bacterial nanocellulose (BNC) magnetic for applications in damaged blood vessel reconstruction. The BNC was synthesized by G. xylinus strain. On the other hand, magnetization of the BNC was realized through in situ precipitation of Fe2+ and Fe3+ ferrous ions inside the BNC mesh.

酸化鉄ナノ粒子との機能を有する磁性細菌Nanocelluloseの作製

In this study, bacterial nanocellulose (BNC) produced by the bacteria Gluconacetobacter xylinus is synthesized and impregnated in situ with iron oxide ...

Solid Lipid Nanoparticles (SLNs) for Intracellular Targeting Applications

Nanoparticle-based delivery vehicles have shown great promise for intracellular targeting applications, providing a mechanism to specifically alter cellular signaling and gene expression. In a previous investigation, the synthesis of ultra-small solid lipid nanoparticles (SLNs) for topical drug delivery and biomarker detection applications was demonstrated. SLNs are a well-studied example of a nanoparticle delivery system that has emerged as a promising drug delivery vehicle. In this study, SLNs were loaded with a fluorescent dye and used as a model to investigate particle-cell interactions. The phase inversion temperature (PIT) method was used for the synthesis of ultra-small populations of biocompatible nanoparticles. A 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenylphenyltetrazolium bromide (MTT) assay was utilized in order to establish appropriate dosing levels prior to the nanoparticle-cell interaction studies. Furthermore, primary human dermal fibroblasts and mouse dendritic cells were exposed to dye-loaded SLN over time and the interactions with respect to toxicity and particle uptake were characterized using fluorescence microscopy and flow cytometry. This study demonstrated that ultra-small SLNs, as a nanoparticle delivery system, are suitable for intracellular targeting of different cell types.

Solid Lipid Nanoparticles SLNs for Intracellular Targeting Applications

In this study, a method for synthesizing ultra-small populations of biocompatible nanoparticles was described, as well as several in vitro methods by which to assess their cellular interactions.

細胞内ターゲティングアプリケーションのための固体脂質ナノ粒子（SLNs）

Nanoparticle-based delivery vehicles have shown great promise for intracellular targeting applications, providing a mechanism to specifically alter ...

Identification of Metal Oxide Nanoparticles in Histological Samples by Enhanced Darkfield Microscopy and Hyperspectral Mapping

Nanomaterials are increasingly prevalent throughout industry, manufacturing, and biomedical research. The need for tools and techniques that aid in the identification, localization, and characterization of nanoscale materials in biological samples is on the rise. Currently available methods, such as electron microscopy, tend to be resource-intensive, making their use prohibitive for much of the research community. Enhanced darkfield microscopy complemented with a hyperspectral imaging system may provide a solution to this bottleneck by enabling rapid and less expensive characterization of nanoparticles in histological samples. This method allows for high-contrast nanoscale imaging as well as nanomaterial identification. For this technique, histological tissue samples are prepared as they would be for light-based microscopy. First, positive control samples are analyzed to generate the reference spectra that will enable the detection of a material of interest in the sample. Negative controls without the material of interest are also analyzed in order to improve specificity (reduce false positives). Samples can then be imaged and analyzed using methods and software for hyperspectral microscopy or matched against these reference spectra in order to provide maps of the location of materials of interest in a sample. The technique is particularly well-suited for materials with highly unique reflectance spectra, such as noble metals, but is also applicable to other materials, such as semi-metallic oxides. This technique provides information that is difficult to acquire from histological samples without the use of electron microscopy techniques, which may provide higher sensitivity and resolution, but are vastly more resource-intensive and time-consuming than light microscopy.

Enhanced darkfield microscopy and hyperspectral imaging with spectral mapping enable screening, localization, and identification of nanoscale materials in histological samples with improved speed and accuracy over traditional methods. The goal of this paper is to provide methods for darkfield imaging and hyperspectral mapping of metal oxide nanoparticles in histological samples.

強化された暗視野顕微鏡とハイパースペクトルマッピングにより組織学的試料中の金属酸化物ナノ粒子の同定

Nanomaterials are increasingly prevalent throughout industry, manufacturing, and biomedical research. The need for tools and techniques that aid in the ...

Microwave-driven Synthesis of Iron Oxide Nanoparticles for Fast Detection of Atherosclerosis

A fast and reproducible microwave-driven protocol has been developed for the synthesis of neridronate-functionalized nanoparticles. Starting from the synthesis of hydrophobic nanoparticles, our method is based on an adaptation from thermal decomposition method to microwave driven synthesis. The new methodology produces a decrease in the reaction times in comparison with traditional procedures. Moreover, the use of the microwave technology increases the reproducibility of the reactions, something important from the point of view of clinical applications. The novelty of this iron oxide nanoparticle is the attachment of Neridronate. The use of this molecule leads a bisphosphonate moiety towards the outside of the nanoparticle that provides Ca2+ binding properties in vitro and selective accumulation in vivo in the atheroma plaque. The protocol allows the synthesis and plaque detection in about 3 hr since the initial synthesis from organic precursors. Their accumulation in the atherosclerotic area in less than 1 hr provides a contrast agent particularly suitable for clinical applications.

Microwave technology enables extremely fast synthesis of iron oxide nanoparticles for atherosclerosis plaque characterization. The use of an aminobisphosphonate in the external side of the nanoparticle provides a fast accumulation in the atherosclerotic area.

アテローム性動脈硬化症の高速検出のための酸化鉄ナノ粒子のマイクロ波駆動型の合成

A fast and reproducible microwave-driven protocol has been developed for the synthesis of neridronate-functionalized nanoparticles. Starting from the ...

Initial Evaluation of Antibody-conjugates Modified with Viral-derived Peptides for Increasing Cellular Accumulation and Improving Tumor Targeting

Antibody-conjugates (ACs) modified with virus-derived peptides are a potentially powerful class of tumor cell delivery agents for molecular payloads used in cancer treatment and imaging due to increased cellular accumulation over current ACs. During early AC in vitro development, fluorescence techniques and radioimmunoassays are sufficient for determining intracellular localization, accumulation efficiency, and target cell specificity. Currently, there is no consensus on standardized methods for preparing cells for evaluating AC intracellular accumulation and localization. The initial testing of ACs modified with virus-derived peptides is critical especially if several candidates have been constructed. Determining intracellular accumulation by fluorescence can be affected by background signal from ACs at the cell surface and complicate the interpretation of accumulation. For radioimmunoassays, typically treated cells are fractionated and the radioactivity in different cell compartments measured. However, cell lysis varies from cell to cell and often nuclear and cytoplasmic compartments are not adequately isolated. This can produce misleading data on payload delivery properties. The intravenous injection of radiolabeled virus-derived peptide-modified ACs in tumor bearing mice followed by radionuclide imaging is a powerful method for determining tumor targeting and payload delivery properties at the in vivo phase of development. However, this is a relatively recent advancement and few groups have evaluated virus-derived peptide-modified ACs in this manner. We describe the processing of treated cells to more accurately evaluate virus-derived peptide-modified AC accumulation when using confocal microscopy and radioimmunoassays. Specifically, a method for trypsinizing cells to remove cell surface bound ACs. We also provide a method for improving cellular fractionation. Lastly, this protocol provides an in vivo method using positron emission tomography (PET) for evaluating initial tumor targeting properties in tumor-bearing mice. We use the radioisotope 64Cu (t1/2 = 12.7 h) as an example payload in this protocol.

Viral-derived peptides coupled to antibody-conjugates (ACs) is an approach gaining momentum due to the potential of delivering molecular payloads with increased tumor cell accumulation. Utilizing common methods to evaluate peptide conjugation, AC and payload intracellular accumulation, and tumor targeting, this protocol helps researchers during the key initial development phases.

細胞集積量の増加と腫瘍標的化の改善のためウイルス由来ペプチド修飾抗体複合体の初期評価

Antibody-conjugates (ACs) modified with virus-derived peptides are a potentially powerful class of tumor cell delivery agents for molecular payloads used ...

Protocol for MicroRNA Transfer into Adult Bone Marrow-derived Hematopoietic Stem Cells to Enable Cell Engineering Combined with Magnetic Targeting

While CD133+ hematopoietic stem cells (SCs) have been proven to provide high potential in the field of regenerative medicine, their low retention rates after injection into injured tissues as well as the observed massive cell death rates lead to very restricted therapeutic effects. To overcome these limitations, we sought to establish a non-viral based protocol for suitable cell engineering prior to their administration. The modification of human CD133+ expressing SCs using microRNA (miR) loaded magnetic polyplexes was addressed with respect to uptake efficiency and safety as well as the targeting potential of the cells. Relying on our protocol, we can achieve high miR uptake rates of 80&#8211;90% while the CD133+ stem cell properties remain unaffected. Moreover, these modified cells offer the option of magnetic targeting. We describe here a safe and highly efficient procedure for the modification of CD133+ SCs. We expect this approach to provide a standard technology for optimization of therapeutic stem cell effects and for monitoring of the administered cell product via magnetic resonance imaging (MRI).

This protocol illustrates a safe and efficient procedure to modify CD133+ hematopoietic stem cells. The presented non-viral, magnetic polyplex-based approach may provide a basis for the optimization of therapeutic stem cell effects as well as for monitoring the administered cell product via magnetic resonance imaging.

成人骨髄由来造血幹細胞が細胞工学磁気ターゲッティングと結合を有効にするにマイクロ Rna の転送のためのプロトコル

While CD133+ hematopoietic stem cells (SCs) have been proven to provide high potential in the field of regenerative medicine, their low retention rates ...

Catalytic Scavenging of Plant Reactive Oxygen Species In Vivo by Anionic Cerium Oxide Nanoparticles

Reactive oxygen species (ROS) accumulation is a hallmark of plant abiotic stress response. ROS play&#160;a dual role in plants by acting as signaling molecules at low levels and damaging molecules at high levels. Accumulation of ROS in stressed plants can damage metabolites, enzymes, lipids, and DNA, causing a reduction of plant growth and yield. The ability of cerium oxide nanoparticles (nanoceria) to catalytically scavenge ROS in vivo provides a unique tool to understand and bioengineer plant abiotic stress tolerance. Here, we present a protocol to synthesize and characterize poly (acrylic) acid coated nanoceria (PNC), interface the nanoparticles with plants via leaf lamina infiltration, and monitor their distribution and ROS scavenging in vivo using confocal microscopy. Current molecular tools for manipulating ROS accumulation in plants are limited to model species and require laborious transformation methods. This protocol for in vivo ROS scavenging has the potential to be applied to wild type plants with broad leaves and leaf structure like Arabidopsis thaliana.

Catalytic Scavenging of Plant Reactive Oxygen Species In Vivo by Anionic Cerium Oxide Nanoparticles

Here, we present a protocol for the synthesis and characterization of cerium oxide nanoparticles (nanoceria) for ROS (reactive oxygen species) scavenging in vivo, nanoceria imaging in plant tissues by confocal microscopy, and in vivo monitoring of nanoceria ROS scavenging by confocal microscopy.

植物活性酸素種体内はアニオン性セリウム酸化物ナノ粒子の触媒の清掃

Reactive oxygen species (ROS) accumulation is a hallmark of plant abiotic stress response. ROS play&#160;a dual role in plants by acting as signaling ...