カナダ衛生研究所（CIHR）、自然科学と工学研究評議会（NSERC）：著者は、次の資金源に感謝したいと思います。

1。 LabVIEWプログラムの開発<ol><li>マスフローコントローラ（MKS M100Bマスフロコントローラ）は、正確なガス流量を確保するために、ヘリウムガスラインに取り付けられている。このユニットは、0から5 V.のLabViewプログラム内の制御ループは、任意の時点で必要な電圧を決定するの範囲の入力電圧によって制御される。コンピュータ及びマスフローコントローラ間のインタフェースは、データ収集装置（NIのUSB-6009）によって行われ、12 V電源は、マスフローコントローラに電力を提供する。 </li><li>二つの位置決めリニアスライドを6ウェルプレート、各方向に1つの動きを制御するために使用される。各アセンブリは、ステッピングモータと連結MA15シリーズVelmex Unislideアセンブリで構成されており、両方のアセンブリは、モータコントローラステッピングシングルVelmex VXMによって制御されます。コントローラは、各モータのマニュアルジョギングを可能にし、または外部シリアルコマンドの文字列を受け取り、特定の動きPを可能にするとの組み合わせatterns。いくつかのパターンは、所望のトーチ速度と経路の寸法を提供するようにユーザに要求する、のLabViewプログラムにプログラムすることができる。 </li></ol> 2。機材の準備<ol><li>ヘリウムボンベとレギュレータの両方を開きます。 </li><li>モータコントローラをオンにします。 </li><li> LabVIEWプログラムを開いて、すべての条件を確認してください。 </li><li>プラットフォームが中心となっていることを確認します。チェック各モータステージを見て、各キャリッジは、ステージ両端付近ではないことを確認します。プログラムセンター馬車持っているか、手動モータコントローラの前面にあるジョギングコントロールを使用して、どちらかの調整。 </li><li>これはその日の最初に実行された場合は、セットアップが正しく動作していることを確認するために、細胞なしで一度プログラムを実行することをお勧めします。 </li></ol> 3。ガスジェットキャピラリーノズル高さの調製<ol><li>ホルダーから毛細血管を削除し、高さのダイヤルをゼロに。 </li><li> 6ウェルプレートを置きoをNプラットフォーム。 </li><li>それはカバーガラスに当たるまで井戸の底にガスジェットキャピラリーを交換し、下げます。ホルダーにキャピラリーを固定します。 </li><li>高さのダイヤルを使用して、キャピラリー3ミリメートルを上げる。キャピラリーベースにこの高さをマーク。 </li><li>安全な高さに毛細血管を上げた後、6ウェルプレートを取り外します。 </li></ol> 4。細胞透過化プロトコル<ol><li>標準的な培養技術を用いて6ウェルプレート中でガラスカバースリップ上でコンフルエント培養する接着細胞株。 HeLa細胞については、ウェル当たり2×10 5細胞で6ウェルプレートに播種し、処理の前に48時間インキュベートする。 </li><li>所望のベクターを含有する溶液の適切なボリュームを準備します。 hrGFPII-1の場合は、1×PBS中50 NG /μLの濃度は、HeLa細胞にトランスフェクション後24時間後に強い蛍光シグナルを提供しています。デキストラン研究のために、10 kDaの緑色蛍光デキストランの80μg/ mlのをお勧めします。以後、この溶液と呼ぶことにするS「ベクター溶液」。 </li><li>ウェルから細胞培養培地を除去し、1×PBSで3回リンスする。 </li><li>井戸にステップ4.2で調製したベクター溶液を1370μlのピペット。これは、約1.3ミリメートルの液体深さをもたらすはずである。 </li><li>プラットフォームの中心にベクター溶液を含む井戸を配置します。スライド上の3ミリメートルのノズル高さを示す以前にマークされたレベルにガスジェットノズルを下げます。 </li><li>のLabViewプログラム内のヘリウムの流量を設定し、使用する所望の移動パターンを選択。とき透過性プロトコルを開始する準備ができて「ファイル名を指定して実行」を選択してください。マスフローコントローラが、必要な流量を提供する準備をしている間、初期誘導期が存在することになる。適切な流量に達すると、のLabViewプログラムは、所望の透過性パターンでウェルを移動させるようにステッパモータを活性化するであろう。プラットフォームが停止すると、約30秒待ってから、ベクター溶液を除去。注：最適な透過性は、毛細管の直径に応じて、ノズル出口で100〜200 Paでの動圧の近くで発生する。 </li><li> 1X PBSでよく3回洗浄する。 </li><li>新鮮な培養培地とよく埋める。 </li><li>実験の目的の数の4.6 - を繰り返して4.3を繰り返します。注：それらの上で実行されているガスジェットずにベクター溶液が充填されたウェルで構成されて対照試料を含めるようにしてください。ステップ4.5および4.6に進み、その後、約1分間の対照ウェル内の溶液を残す。 </li><li> hrGFPのトランスフェクション実験を実行している場合は、トランスフェクトされた物質は、細胞によって転写されるように24時間インキュベーターに6ウェルプレートを返す。デキストラン透過性実験を実行している場合は、15分間インキュベーターに6ウェルプレートを返す。 </li></ol> 5。細胞画像化<ol><li>必要に応じて、すぐに画像化する前に、細胞死を評価するために、適切な生/死染色で対比染色。 </li><li> appropと画像セルトランスフェクション/透過化の有効性を調査するriate顕微鏡。 </li></ol>

<ol>
	<li>Rosenberg, S. 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=Gene+transfer+into+humans--immunotherapy+of+patients+with+advanced+melanoma,+using+tumor-infiltrating+lymphocytes+modified+by+retroviral+gene+transduction.">Gene transfer into humans--immunotherapy of patients with advanced melanoma, using tumor-infiltrating lymphocytes modified by retroviral gene transduction.</a> The New England Journal of Medicine. 323, 570-578 (1990).</li><li>Yang, Y., 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=Cellular+immunity+to+viral+antigens+limits+E1-deleted+adenoviruses+for+gene+therapy.">Cellular immunity to viral antigens limits E1-deleted adenoviruses for gene therapy.</a> Proceedings of the National Academy of Sciences of the United States of America. 91, 4407-4411 (1994).</li><li>Chen, C., Okayama, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High-efficiency+transformation+of+mammalian+cells+by+plasmid+DNA.">High-efficiency transformation of mammalian cells by plasmid DNA.</a> Molecular and cellular biology. 7, 2745-2752 (1987).</li><li>Walev, I., 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=Delivery+of+proteins+into+living+cells+by+reversible+membrane+permeabilization+with+streptolysin-O.">Delivery of proteins into living cells by reversible membrane permeabilization with streptolysin-O.</a> Proceedings of the National Academy of Sciences of the United States of America. 98, 3185-3190 (2001).</li><li>Felgner, P. L., 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=Lipofection:+a+highly+efficient,+lipid-mediated+DNA-transfection+procedure.">Lipofection: a highly efficient, lipid-mediated DNA-transfection procedure.</a> Proceedings of the National Academy of Sciences of the United States of America. 84, 7413-7417 (1987).</li><li>Hamm, A., Krott, N., Breibach, I., Blindt, R., Bosserhoff, A. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Efficient+transfection+method+for+primary+cells.">Efficient transfection method for primary cells.</a> Tissue engineering. 8, 235-245 (2002).</li><li>Rauth, S., Kucherlapati, R. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Expression+of+DNA+Transferred+into+Mammalian-Cells.">Expression of DNA Transferred into Mammalian-Cells.</a> J. Bioscience. 6, 543-567 (1984).</li><li>Spandidos, D. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electric+field-mediated+gene+transfer+(electroporation)+into+mouse+Friend+and+human+K562+erythroleukemic+cells.">Electric field-mediated gene transfer (electroporation) into mouse Friend and human K562 erythroleukemic cells.</a> Gene analysis techniques. 4, 50-56 (1987).</li><li>Chu, G., Hayakawa, H., Berg, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electroporation+for+the+efficient+transfection+of+mammalian+cells+with+DNA.">Electroporation for the efficient transfection of mammalian cells with DNA.</a> Nucleic Acids Research. 15, 1311-1326 (1987).</li><li>Fechheimer, 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=Transfection+of+mammalian+cells+with+plasmid+DNA+by+scrape+loading+and+sonication+loading.">Transfection of mammalian cells with plasmid DNA by scrape loading and sonication loading.</a> Proceedings of the National Academy of Sciences of the United States of America. 84, 8463-8467 (1987).</li><li>Koch, S., Pohl, P., Cobet, U., Rainov, N. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ultrasound+enhancement+of+liposome-mediated+cell+transfection+is+caused+by+cavitation+effects.">Ultrasound enhancement of liposome-mediated cell transfection is caused by cavitation effects.</a> Ultrasound in Medicine &amp; Biology. 26, 897-903 (2000).</li><li>Greenleaf, W. J., Bolander, M. E., Sarkar, G., Goldring, M. B., Greenleaf, J. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Artificial+cavitation+nuclei+significantly+enhance+acoustically+induced+cell+transfection.">Artificial cavitation nuclei significantly enhance acoustically induced cell transfection.</a> Ultrasound in Medicine &amp; Biology. 24, 587-595 (1998).</li><li>Yang, N. S., Burkholder, J., Roberts, B., Martinell, B., McCabe, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vivo+and+in+vitro+gene+transfer+to+mammalian+somatic+cells+by+particle+bombardment.">In vivo and in vitro gene transfer to mammalian somatic cells by particle bombardment.</a> Proceedings of the National Academy of Sciences of the United States of America. 87, 9568-9572 (1990).</li><li>Hallow, D. 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=Shear-induced+intracellular+loading+of+cells+with+molecules+by+controlled+microfluidics.">Shear-induced intracellular loading of cells with molecules by controlled microfluidics.</a> Biotechnology and Bioengineering. 99, 846-854 (2008).</li><li>Chouinard-Pelletier, G. L., Guay, M., Coulombe, D., Leask, S., L, R., Jones, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Use+of+inert+gas+jets+to+measure+the+forces+required+for+mechanical+gene+transfection.">Use of inert gas jets to measure the forces required for mechanical gene transfection.</a> Biomedical Engineering Online. 11, (2012).</li><li>Leduc, M., Coulombe, S., Leask, R. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Atmospheric+Pressure+Plasma+Jet+Deposition+of+Patterned+Polymer+Films+for+Cell+Culture+Applications.">Atmospheric Pressure Plasma Jet Deposition of Patterned Polymer Films for Cell Culture Applications.</a> Ieee T. Plasma Sci. 37, 927-933 (2009).</li><li>Lu, 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=Microfluidic+shear+devices+for+quantitative+analysis+of+cell+adhesion.">Microfluidic shear devices for quantitative analysis of cell adhesion.</a> Analytical Chemistry. 76, 5257-5264 (2004).</li><li>Sankin, G. N., Yuan, F., Zhong, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pulsating+tandem+microbubble+for+localized+and+directional+single-cell+membrane+poration.">Pulsating tandem microbubble for localized and directional single-cell membrane poration.</a> Physical Review Letters. 105, 078101 (2010).</li></ol>

著者は、彼らが競合する金融利害関係はありません宣言します。

不活性ガスジェット透過化は、付着細胞のトランスフェクションのために有用な技術である。これは、潜在的に有害な化学物質又はウイルスベクターの必要性を排除する機械的な力の使用で細胞に生体分子を転送する能力を提供する。技術は、潜在的に研究者や臨床医に正確に細胞をトランスフェクトするための効率的かつ比較的簡単な方法を与えることができる。透過化の選択性はまた、?...

生物医学の進化と細胞の力学を理解し、細胞への生体分子の送達は、多くの研究分野や医学療法に不可欠となっています。異なる技術は、原形質膜を通って細胞サイトゾル内に外来分子を導入するために開発されてきた。ウイルス、化学的または機械的技術：これらは一般的にのいずれかとして分類することができる。ウイルス技術は、ウイルスベクター1を用いたRNAやDNAなどの遺伝物質をトランスフェクトすることができる。ウイルス技術は、しかしながら、それらは免疫および炎症反応の2の可能性を持っている、ある種の細胞株において高い効率を有する傾向がある。一般的な化学的トランスフェクション法は、リン酸カルシウム3、細菌外毒素4とリポフェクション5での沈殿が含まれています。これらの技術は有効であることが証明されているが、特定の問題は、細胞毒性および非特異性として生じる。さらに、このようなカルシウムのような技術phosphat電子沈殿はほとんどの初代細胞6に、最大70％までしか特定の細胞株においてトランスフェクション効率を有することが見出されている。これは、特に臨床用途およびDNAの機能の研究のための様々な治療を設計する場合には、一次細胞中に入れられている研究努力を増大させるように注目すべきである。 機械的刺激を介して細胞膜の一時的な破壊は、細胞に外来分子を導入するための代替手段である。技法としては、分子が7のマイクロインジェクション、膜8,9を破壊電界を用いてエレクトロポレーション、ソノポレーションが結合した粒子を撮影する「遺伝子銃」によって示されるように、細胞膜10-12、粒子ボンバードメントを破壊するために超音波を使用してセル13への遺伝子、およびより最近では、時間的に哺乳動物細胞を14,15を透過することが示されている流体せん断応力を印加する。メカニックもののらの方法は、前述の問題の一部を回避するため、それらは一般的に低い効率と、非常に複雑で専門的なセットアップを伴う。大気圧グロー放電トーチ（APGD-T）は、表面を機能化し、インビトロ 16 に付着した細胞を剥離の初期目標にマギルで開発されました。偶然、それが使用されている生/死染色は、何らかの形で浸透化剤が添加されずに細胞に取り込まれていたことが発見されました。さらに、これが唯一のトーチ·パスと一致するように起こった井戸の制限区域で発生しているように見えた。 APGD-tは透過処理能力の調査を継続し、コントロール研究においては、励起することなく、プラズマの不活性キャリアガスジェットはまた、細胞を透過することができたことがわかった。これは、プラズマジェットによって作成された反応種を一時的に膜の機能を損なわ初期仮説に矛盾を提示単にそのmechani校正力は、細胞透過を引き起こすのに十分であった。ここから、研究は試してみて、定量化し、透過処理、不活性ガスジェットの効率だけでなく、そのトランスフェクション能力16を見て特徴づけるために私たちの研究室で継続。 これらの研究を通して、それは微細孔が原形質膜における実際の形で行うことが見出されており、これらの孔は、約5〜15秒以内に再密封する傾向がある。我々は、ニワトリ胚の漿尿膜のin vitroおよびin vivoでの技術の有用性を実証した。

<table border="1">
	<tbody>
		<tr>
			<td>Vitality hrGFPII-1</td>
			<td>Agilent Technologies Canada</td>
			<td>240143-57</td>
			<td>Green fluorescent protein for transfection experiments on HeLa cells</td>
		</tr>
		<tr>
			<td>Dextran, AlexaFluor 488; 10,000 MW, Anionic, Fixable</td>
			<td>Life Technologies Inc.</td>
			<td>D22910</td>
			<td>dextran for permeabilization experiments</td>
		</tr>
		<tr>
			<td>LIVE/DEAD Viability/Cytotoxicity Kit</td>
			<td>Life Technologies Inc.</td>
			<td>L3224</td>
			<td>for counterstaining of mammalian cells</td>
		</tr>
		<tr>
			<td>Prolong Gold Antifade Reagent</td>
			<td>Invitrogen</td>
			<td>P36930</td>
			<td>for mounting slides when imaging</td>
		</tr>
		<tr>
			<td>Ultra High Purity Helium</td>
			<td>Praxair Canada Inc.</td>
			<td>HE 5.0UH-T</td>
			<td></td>
		</tr>
		<tr>
			<td>Hyclone DMEM/ High Glucose Media - 500 ml</td>
			<td>Thermo Scientific</td>
			<td>SH30022.01</td>
			<td>for HeLa cells</td>
		</tr>
		<tr>
			<td>Fetal Bovine Serum</td>
			<td>Invitrogen</td>
			<td>26140079</td>
			<td>For DMEM media</td>
		</tr>
		<tr>
			<td>Penicillin-Streptomycin, liquid</td>
			<td>Invitrogen</td>
			<td>15140-122</td>
			<td>For DMEM media</td>
		</tr>
		<tr>
			<td>Phosphate-Buffered Saline (PBS) 1x</td>
			<td></td>
			<td></td>
			<td>Produced in lab</td>
		</tr>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td>Table 1. List of required reagents</td>
		</tr>
		<tr>
			<td>6-Well Clear TC-Treated Microplates</td>
			<td>Corning</td>
			<td>3506</td>
			<td></td>
		</tr>
		<tr>
			<td>#1 22 x 22 Coverslips</td>
			<td>Fisher</td>
			<td>12-542B</td>
			<td></td>
		</tr>
		<tr>
			<td>Glass Capillaries</td>
			<td>World Precision Instruments</td>
			<td></td>
			<td>WPI Sizing Information</td>
		</tr>
		<tr>
			<td>ID (mm): 1, 0.86, 0.68, 0.5 Order #: 1B200, 1B150, 1B120, 1B100</td>
		</tr>
		<tr>
			<td>Mass-Flo Controller</td>
			<td>MKS</td>
			<td>M100B01314CS1BV</td>
			<td>Mass flow controller, Series M100B, requires an external 12 V power supply</td>
		</tr>
		<tr>
			<td>USB-6009 DAQ Device</td>
			<td>National Instruments</td>
			<td>779026-01</td>
			<td></td>
		</tr>
		<tr>
			<td>UniSlide Assembly with stepping motor and controller</td>
			<td>Velmex</td>
			<td></td>
			<td>Two series MA15 UniSlide Assemblies, fitted with Vexta 1.8&#176; stepping motors provided by Velmex, and controlled by a VXM Stepping Motor Controller</td>
		</tr>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td>Table 2. List of required equipment</td>
		</tr>
	</tbody>
</table>

permeabilization of adhered cells using an inert gas jet

様々な細胞トランスフェクション技術が存在し、これらは3つのカテゴリーに分けることができます：ウイルス、化学的および機械的。このプロトコルは、時間的に細胞内に通常は非透過性の巨大分子の伝達を容易にすることができる不活性ガスジェットを用いて付着細胞を透過性にするための機械的方法を記載する。我々は、この技術は、マイクロポアの一時的な形成をもたらす、接着細胞の原形質膜上に剪断力を付与することによって機能すると考えている。これらの孔が作成されると、次いで、細胞を遺伝物質および他の生体分子に対して透過性である。関係する機械的な力は、その基板から完全に損傷または取り外し細胞のリスクを実行します。技術が有効である不活性気体力学の狭い範囲は、したがって、存在する。不活性ガスジェットは、HeLa、HEK293およびヒト腹部大動脈内皮細胞を含む種々の接着性細胞株を効率的に透過性であることが証明されている。このプロトコルは、Pに適しています我々は、研究のために、潜在的に将来の臨床用途に使用することができる示し、 インビボで実証したように、両方のin vitroでの接着細胞のermeabilizationと、。また、貴重な研究ツールであることを証明する可能性が、空間的に限定的に細胞を透過性という利点があります。

0.86ミリメートルの内径を有する毛管ヘリウムガスジェットを用いた10kDaの緑色蛍光デキストランHeLa細胞の透過処理は、 図1に示されている。細胞は、細胞死を可視化する2μL/ mlののEthD-1溶液（生/死生存率/細胞毒性キット）で、すぐに透過処理した後に染色した。すぐに対比以下、カバースリップをマウントし、画像化した。この図は、対照試料と比較して、三つの異なる出口圧...

Watch this Scientific Journal Video about Permeabilization of Adhered Cells Using an Inert Gas Jet at JoVE.com

Permeabilization of Adhered Cells Using an Inert Gas Jet

このプロトコルは、不活性ガスジェットを用いた接着細胞の一時的な透過化のための方法を記載している。この技術は、原形質膜を破壊する機械的な力を利用することにより接着性哺乳動物細胞への遺伝物質および生体分子の移動を容易にする。

不活性ガスジェットを用いて接着した細胞の透過性

Various cell transfection techniques exist and these can be broken down to three broad categories: viral, chemical and mechanical. This protocol describes ...

permeabilization-of-adhered-cells-using-an-inert-gas-jet

Research

JoVE Journal

Bioengineering

9.6K ビュー.  McGill University. このプロトコルは、不活性ガスジェットを用いた接着細胞の一時的な透過化のための方法を記載している。この技術は、原形質膜を破壊する機械的な力を利用することにより接着性哺乳動物細胞への遺伝物質および生体分子の移動を容易にする。 

ビデオ: Permeabilization of Adhered Cells Using an Inert Gas Jet

Qualitative Characterization of the Aqueous Fraction from Hydrothermal Liquefaction of Algae Using 2D Gas Chromatography with Time-of-flight Mass Spectrometry

Two-dimensional gas chromatography coupled with time-of-flight mass spectrometry is a powerful tool for identifying and quantifying chemical components in complex mixtures. It is often used to analyze gasoline, jet fuel, diesel, bio-diesel and the organic fraction of bio-crude/bio-oil. In most of those analyses, the first dimension of separation is non-polar, followed by a polar separation. The aqueous fractions of bio-crude and other aqueous samples from biofuels production have been examined with similar column combinations. However, sample preparation techniques such as derivatization, solvent extraction, and solid-phase extraction were necessary prior to analysis. In this study, aqueous fractions obtained from the hydrothermal liquefaction of algae were characterized by two-dimensional gas chromatography coupled with time-of-flight mass spectrometry without prior sample preparation techniques using a polar separation in the first dimension followed by a non-polar separation in the second. Two-dimensional plots from this analysis were compared with those obtained from the more traditional column configuration. Results from qualitative characterization of the aqueous fractions of algal bio-crude are discussed in detail. The advantages of using a polar separation followed by a non-polar separation for characterization of organics in aqueous samples by two-dimensional gas chromatography coupled with time-of-flight mass spectrometry are highlighted.

A two-dimensional gas chromatography-time-of-flight mass spectrometry method is described for characterization of the aqueous fraction of bio-crude produced from hydrothermal liquefaction of algae. This protocol can also be employed to analyze the aqueous fraction of liquid products from fast pyrolysis, catalytic fast pyrolysis, catalytic deoxygenation and hydro-treating.

飛行時間型質量分析法と2Dガスクロマトグラフィーを用いて藻類の水熱液化からの水性画分の質的特性評価

Two-dimensional gas chromatography coupled with time-of-flight mass spectrometry is a powerful tool for identifying and quantifying chemical components in ...

生物工学

Quantifying Microorganisms at Low Concentrations Using Digital Holographic Microscopy (DHM)

Accurately detecting and counting sparse bacterial samples has many applications in the food, beverage, and pharmaceutical processing industries, in medical diagnostics, and for life detection by robotic missions to other planets and moons of the solar system. Currently, sparse bacterial samples are counted by culture plating or epifluorescence microscopy. Culture plates require long incubation times (days to weeks), and epifluorescence microscopy requires extensive staining and concentration of the sample. Here, we demonstrate how to use off-axis digital holographic microscopy (DHM) to enumerate bacteria in very dilute cultures (100-104 cells/mL). First, the construction of the custom DHM is discussed, along with detailed instructions on building a low-cost instrument. The principles of holography are discussed, and a statistical model is used to estimate how long videos should be to detect cells, based on the optical performance characteristics of the instrument and the concentration of the bacterial solution (Table 2). Video detection of cells at 105, 104, 103, and 100 cells/mL is demonstrated in real time using un-reconstructed holograms. Reconstruction of amplitude and phase images is demonstrated using an open-source software package.

Quantifying Microorganisms at Low Concentrations Using Digital Holographic Microscopy DHM

Digital holographic microscopy (DHM) is a volumetric technique that allows imaging samples 50-100X thicker than brightfield microscopy at comparable resolution, with focusing performed post-processing. Here DHM is used for identifying, counting, and tracking microorganisms at very low densities and compared with optical density measurements, plate count, and direct count.

デジタル ホログラフィー顕微鏡 (DHM) を用いた低濃度で微生物の定量化

Accurately detecting and counting sparse bacterial samples has many applications in the food, beverage, and pharmaceutical processing industries, in ...

High-resolution Patterning Using Two Modes of Electrohydrodynamic Jet: Drop on Demand and Near-field Electrospinning

Electrohydrodynamic (EHD) jet printing has drawn attention in various fields because it can be used as a high-resolution and low-cost direct patterning tool. EHD printing uses a fluidic supplier to maintain the extruded meniscus by pushing the ink out of the nozzle tip. The electric field is then used to pull the meniscus down to the substrate to produce high-resolution patterns. Two modes of EHD printing have been used for fine patterning: continuous near-field electrospinning (NFES) and dot-based drop-on-demand (DOD) EHD printing. According to the printing modes, the requirements for the printing equipment and ink viscosity will differ. Even though two different modes can be implemented with a single EHD printer, the realization methods significantly differ in terms of ink, fluidic system, and driving voltage. Consequently, without a proper understanding of the jetting requirements and limitations, it is difficult to obtain the desired results. The purpose of this paper is to present a guideline so that inexperienced researchers can reduce the trial and error efforts to use the EHD jet for their specific research and development purposes. To demonstrate the fine-patterning implementation, we use Ag nanoparticle ink for the conductive patterning in the protocol. In addition, we also present the generalized printing guidelines that can be used for other types of ink for various fine-patterning applications.

Here, we present a protocol to produce high-resolution conductive patterns using electrohydrodynamic (EHD) jet printing. The protocol includes two modes of EHD jet printing: the continuous near-field electrospinning (NFES) and the dot-based drop-on-demand (DOD) EHD printing.

パターン化する電気流体力学的ジェットの 2 つのモードを使用して高解像度: 需要と近傍電界紡糸ドロップ

Electrohydrodynamic (EHD) jet printing has drawn attention in various fields because it can be used as a high-resolution and low-cost direct patterning ...

A Novel Surgical Technique As a Foundation for In Vivo Partial Liver Engineering in Rat

Organ engineering is a novel strategy to generate liver organ substitutes that can potentially be used in transplantation. Recently, in vivo liver engineering, including in vivo organ decellularization followed by repopulation, has emerged as a promising approach over ex vivo liver engineering. However, postoperative survival was not achieved. The aim of this study is to develop a novel surgical technique of in vivo selective liver lobe perfusion in rats as a prerequisite for in vivo liver engineering. We generate a circuit bypass only through the left lateral lobe. Then, the left lateral lobe is perfused with heparinized saline. The experiment is performed with 4 groups (n = 3 rats per group) based on different perfusion times of 20 min, 2 h, 3 h, and 4 h. Survival, as well as the macroscopically visible change of color and the histologically determined absence of blood cells in the portal triad and the sinusoids, is taken as an indicator for a successful model establishment. After selective perfusion of the left lateral lobe, we observe that the left lateral lobe, indeed, turned from red to faint yellow. In a histological assessment, no blood cells are visible in the branch of the portal vein, the central vein, and the sinusoids. The left lateral lobe turns red after reopening the blocked vessels. 12/12 rats survived the procedure for more than one week. We are the first to report a surgical model for in vivo single liver lobe perfusion with a long survival period of more than one week. In contrast to the previously published report, the most important advantage of the technique presented here is that perfusion of 70% of the liver is maintained throughout the whole procedure. The establishment of this technique provides a foundation for in vivo partial liver engineering in rats, including decellularization and recellularization.

A Novel Surgical Technique As a Foundation for In Vivo Partial Liver Engineering in Rat

We establish a novel surgical technique for an in vivo single liver lobe perfusion model in rat as a prerequisite for further studying in vivo partial liver engineering in the future.

ラットでの肝部分工学生体内での基盤として新しい手術手技

Organ engineering is a novel strategy to generate liver organ substitutes that can potentially be used in transplantation. Recently, in vivo liver ...

Purification and Analytics of a Monoclonal Antibody from Chinese Hamster Ovary Cells Using an Automated Microbioreactor System

Monoclonal antibodies (mAbs) are one of the most popular and well-characterized biological products manufactured today. Most commonly produced using Chinese hamster ovary (CHO) cells, culture and process conditions must be optimized to maximize antibody titers and achieve target quality profiles. Typically, this optimization uses automated microscale bioreactors (15 mL) to screen multiple process conditions in parallel. Optimization criteria include culture performance and the critical quality attributes (CQAs) of the monoclonal antibody (mAb) product, which may impact its efficacy and safety. Culture performance metrics include cell growth and nutrient consumption, while the CQAs include the mAb's N-glycosylation and aggregation profiles, charge variants, and molecular weight. This detailed protocol describes how to purify and subsequently analyze HCCF samples produced by an automated microbioreactor system to gain valuable performance metrics and outputs. First, an automated protein A fast protein liquid chromatography (FPLC) method is used to purify the mAb from harvested cell culture samples. Once concentrated, the glycan profiles are analyzed by mass spectrometry using a specific platform (refer to the Table of Materials). Antibody molecular weights and aggregation profiles are determined using size exclusion chromatography-multiple angle light scattering (SEC-MALS), while charge variants are analyzed using microchip capillary zone electrophoresis (mCZE). In addition to the culture performance metrics captured during the bioreactor process (i.e., culture viability, cell counts, and common metabolites including glutamine, glucose, lactate, and ammonia), spent media is analyzed to identify limiting nutrients to improve the feeding strategies and overall process design. Therefore, a detailed protocol for the absolute quantification of amino acids by liquid chromatography-mass spectrometry (LC-MS) of spent media is also described. The methods used in this protocol take advantage of high-throughput platforms that are compatible for large numbers of small-volume samples.

A detailed protocol for the purification and subsequent analysis of a monoclonal antibody from harvested cell culture fluid (HCCF) of automated microbioreactors has been described. Use of analytics to determine critical quality attributes (CQAs) and maximizing limited sample volume to extract vital information is also presented.

自動化された微生物叢システムを用いた中国ハムスター卵巣細胞からのモノクローナル抗体の精製と分析

Monoclonal antibodies (mAbs) are one of the most popular and well-characterized biological products manufactured today. Most commonly produced using ...

Screening and Identification of Small Peptides Targeting Fibroblast Growth Factor Receptor2 using a Phage Display Peptide Library

The human Fibroblast Growth Factor Receptor (FGFR) family comprises four members, namely, FGFR1, FGFR2, FGFR3, and FGFR4, that are involved in various biological activities including cell proliferation, survival, migration and differentiation. Several aberrations in the FGFR signaling pathway, owing to mutations or gene amplification events, have been identified in various types of cancers. Hence, recent research has focused on developing strategies involving therapeutic targeting of FGFRs. Current FGFR inhibitors at various stages of pre-clinical and clinical development include either small molecule inhibitors of tyrosine kinases or monoclonal antibodies, with only a few peptide- based inhibitors in the pipeline. Here, we provide a protocol using phage display technology to screen small peptides as antagonists of FGFR2. Briefly, a library of phage-displayed peptides was incubated in a plate coated with FGFR2. Subsequently, unbound phage was washed off by TBST (TBS + 0.1% [v/v] Tween-20), and bound phage was eluted with 0.2 M glycine-HCl buffer (pH 2.2). The eluted phage was further amplified and used as input for the next round of biopanning. Following three rounds of biopanning, the peptide sequences of individual phage clones were identified by DNA sequencing. Finally, the screened peptides were synthesized and analyzed for affinity and biological activity.

Herein, we present a detailed protocol for screening small peptides that bind to FGFR2 using a phage display peptide library. We further analyze the affinity of the selected peptides toward FGFR2 in vitro and its ability to suppress cell proliferation.

ファージ表示ペプチドライブラリーを用いて線維芽細胞増殖因子受容体2を標的とする小ペプチドのスクリーニングと同定

The human Fibroblast Growth Factor Receptor (FGFR) family comprises four members, namely, FGFR1, FGFR2, FGFR3, and FGFR4, that are involved in various ...

The Fabrication and Operation of a Continuous Flow, Micro-Electroporation System with Permeabilization Detection

Current therapeutic innovations, such as CAR-T cell therapy, are heavily reliant on viral-mediated gene delivery. Although efficient, this technique is accompanied by high manufacturing costs, which has brought about an interest in using alternative methods for gene delivery. Electroporation is an electro-physical, non-viral approach for the intracellular delivery of genes and other exogenous materials. Upon the application of an electric field, the cell membrane temporarily allows molecular delivery into the cell. Typically, electroporation is performed on the macroscale to process large numbers of cells. However, this approach requires extensive empirical protocol development, which is costly when working with primary and difficult-to-transfect cell types. Lengthy protocol development, coupled with the requirement of large voltages to achieve sufficient electric-field strengths to permeabilize the cells, has led to the development of micro-scale electroporation devices. These micro-electroporation devices are manufactured using common microfabrication techniques and allow for greater experimental control with the potential to maintain high throughput capabilities. This work builds off a microfluidic-electroporation technology capable of detecting the level of cell membrane permeabilization at a single-cell level under continuous flow. However, this technology was limited to 4 cells processed per second, and thus a new approach for increasing the system throughput is proposed and presented here. This new technique, denoted as cell-population-based feedback control, considers the cell permeabilization response to a variety of electroporation pulsing conditions and determines the best-suited electroporation pulse conditions for the cell type under test. A higher-throughput mode is then used, where this 'optimal' pulse is applied to the cell suspension in transit. The steps for fabricating the device, setting up and running the microfluidic experiments, and analyzing the results are presented in detail. Finally, this micro-electroporation technology is demonstrated by delivering a DNA plasmid encoding for green fluorescent protein (GFP) into HEK293 cells.

This protocol describes the microfabrication techniques required to build a lab-on-a-chip, microfluidic electroporation device. The experimental setup performs controlled, single-cell-level transfections in a continuous flow and can be extended to higher throughputs with population-based control. An analysis is provided showcasing the ability to electrically monitor the degree of cell membrane permeabilization in real-time.

透過処理検出機能付き連続フローマイクロエレクトロポレーションシステムの構築と運用

Current therapeutic innovations, such as CAR-T cell therapy, are heavily reliant on viral-mediated gene delivery. Although efficient, this technique is ...

Formulating and Characterizing an Exosome-based Dopamine Carrier System

Exosomes between 40 and 200 nm in size constitute the smallest subgroup of extracellular vesicles. These bioactive vesicles secreted by cells play an active role in intercellular cargo and communication. Exosomes are mostly found in body fluids such as plasma, cerebrospinal fluid, urine, saliva, amniotic fluid, colostrum, breast milk, joint fluid, semen, and pleural acid. Considering the size of exosomes, it is thought that they may play an important role in central nervous system diseases because they can pass through the blood-brain barrier (BBB). Hence, this study aimed to develop an exosome-based nanocarrier system by encapsulating dopamine into exosomes isolated from Wharton's jelly mesenchymal stem cells (WJ-MSCs). Exosomes that passed the characterization process were incubated with dopamine. The dopamine-loaded exosomes were recharacterized at the end of incubation. Dopamine-loaded exosomes were investigated in drug release and cytotoxicity assays. The results showed that dopamine could be successfully encapsulated within the exosomes and that the dopamine-loaded exosomes did not affect fibroblast viability.

Here, we aimed to obtain a formulation by dopamine loading of the isolated exosomes of stem cells from Wharton's jelly mesenchymal stem cells. Exosome isolation and characterization, drug loading into the resulting exosomes, and the cytotoxic activity of the developed formulation are described in this protocol.

エクソソームベースのドーパミンキャリアシステムの定式化と特性評価

Exosomes between 40 and 200 nm in size constitute the smallest subgroup of extracellular vesicles. These bioactive vesicles secreted by cells play an ...

CIJおよびμMIVMミキサー技術を用いた脂質ナノ粒子の合成

Synthesizing Lipid Nanoparticles by Turbulent Flow in Confined Impinging Jet Mixers

Lipid nanoparticles (LNPs) have demonstrated their enormous potential as therapeutic delivery vehicles, as evidenced by the approval and global usage of two COVID-19 messenger RNA (mRNA) vaccines. On a small scale, LNPs are often made using microfluidics; however, the limitations of these devices preclude their use on a large scale. The COVID-19 vaccines are manufactured in large quantities using confined impinging jet (CIJ) turbulent mixers. CIJ technology enables production at a laboratory scale with the confidence that it can be scaled to production volumes. The key concepts in CIJ mixing are that the mixing length and time scale are determined by the turbulence intensity in the mixing cavity and that the nanoparticle formation occurs away from walls, eliminating the problem of deposition on surfaces and fouling. This work demonstrates the process of making LNPs using confined impinging jet mixer technology with two geometries: the two-jet CIJ and the four-jet multi-inlet vortex mixer (MIVM). The advantages and disadvantages of each mixing geometry are discussed. In these geometries, LNPs are formed by rapid mixing of an organic solvent stream (usually ethanol containing the ionizable lipids, co-lipids, and stabilizing PEG-lipids) with an aqueous anti-solvent stream (aqueous buffer containing RNA or DNA). The operating parameters for the CIJ and MIVM mixers are presented to prepare reproducible LNPs with controlled size, zeta potential, stability, and transfection effectiveness. The differences between LNPs made with poor mixing (pipetting solutions) compared to CIJ mixing are also presented.

著者スポットライト:閉じ込められた形状における乱流混合による脂質ナノ粒子形成の促進

A detailed protocol for synthesizing lipid nanoparticles (LNPs) using confined impinging jet (CIJ) mixer technologies, including a two-jet CIJ and a four-jet multi-inlet vortex mixer (&#181;MIVM), is demonstrated. The CIJ mixers generate reproducible, turbulent micro-mixing environments, resulting in the production of monodisperse LNPs.

閉じ込めインピンギングジェットミキサーにおける乱流による脂質ナノ粒子の合成

Lipid nanoparticles (LNPs) have demonstrated their enormous potential as therapeutic delivery vehicles, as evidenced by the approval and global usage of ...