This work was supported by the EC within the framework of the STIFF-FLOP FP7-ICT-2011.2.1 European Project (#287728).

注：このプロトコルは、チャネル、作動パイプラインと外部シースを補強、流体室を含む単一モジュールの製造段階を説明しています。次の手順は、ドラフトおよび安全上の理由から白衣、手袋を着用して下で実行されなければなりません。前述したように、エラストマーユニットの製造工程は、CADソフトウェアで設計金型の連続使用に基づいています。これらは、 図2に示し、表1に列挙される 13個で構成されています。 シリコーンの調製<ol><li>同じプラスチックガラスやシャーレに部分Aを12gとパートBを12gを秤量し、それらを一緒に混合、撹拌。 注：パートA（塩基）及びパートB（触媒）：素材の割合は、使用される特定のシリコーンに応じて変化することができ、この場合には、2つの部分からなります。重量1B：これらは、比例1Aに使用されています。 </li><li>ミックスを含有するガラスを置きます1バールの真空圧力で脱ガス装置にシリコーン材料を編すべてのバブルは、シリコーン材料から除去されるまで真空下でガラスを保管​​してください。採用シリコーンについて脱ガス処理は、約10分かかります。材料は気泡の存在から完全に自由になったら、マシンに大気圧を回復したシリコーンを使用しています。 </li></ol> Siliconicモジュールの2製作<ol><li>金型の組立体。 <ol><li> cap_Aに補剛筒と室の上部を挿入します（ 図3a）。 </li><li> cap_Aの第二の層の周りにシェルを閉じます。 </li></ol></li><li>まずシリコーンキャスティング。 <ol><li>シェル（ 図3b）の端に組み立てられた金型までの内部のシリコーンを注ぎます。 </li><li>約30分間60℃のオーブンで金型を置きます。 </li></ol></li><li>金型の転位。 <ol><li>外部シェルを削除し、cap_A（ 図3C）。 </li><li>室の拠点とcap_B（ 図3d）の内部補強シリンダーからシリンダーを挿入します。 </li><li>モジュールの上面とシェル（ 図3E）のエッジ間10mmのギャップを持つために上方10mmのそれらを滑り、モジュールの周りに再び殻を閉じます。 </li></ol></li><li>第二に、シリコーンキャスティング。 <ol><li>上側のシェルの端に再配置の金型までの内側にシリコンを注ぐ（すなわちまた、補強シリンダーまで）（ 図3F）。 </li><li>約30分間60℃のオーブンに型を入れてください。 </li><li>外部シェルを削除し、cap_Bと（補強筒を除く）室（ 図3G）。 </li></ol></li></ol>チューブの挿入3. <ol><li>同じ所望の長さ（例えば300ミリメートル）に3つの管をカットします。 </li><li> OBのない、10ミリメートルのために各管の一方の端部の周りにsiliconic接着剤を入れてチューブをstructing。 </li><li> siliconicユニット（ 図3H）で2ミリメートル専用チャネルの内側にチューブを挿入します。 </li><li>室温で12分の硬化時間を許可するか、より高い温度でオーブン内部のモジュールを置く - 乾燥プロセスをスピードアップするために（50°〜60°）。 </li></ol>圧着編組シースの4作製<ol><li>拡張可能な編組シース（モジュールの約15倍の高さ）の700ミリメートルをカット。 </li><li>直径30mmとシース内部の長さは250ミリメートルの金属製の円筒を挿入します。 </li><li>押し下げと捲縮を作成するために、筒の上にスライドさせてシースを強制します。 </li><li>永久変形が得られるまで、機械的に2〜3分間、350℃で加熱ガンでクランプし、熱のある場所でシースを固定します。 </li><li>シースはクールダウンし、内筒を削除してみましょう。 </li></ol>外部シースの5統合<ol><li>合格しますcap_Cのスルーホールチューブ。 </li><li> cap_Cにシリコンの3グラムを注ぎます。 </li><li>作業面よりも高いサポートにcap_Cを固定します。 </li><li>以前cap_Cに加工モジュールの底面側を挿入します。 </li><li>モジュールの周りにクリンプシースをスライドさせます。 </li><li> cap_C内側シースの最初のひだを押して、新鮮に注ぎ、シリコーン（ 図3I）にそれらを浸し。 </li><li>約20分間60℃のオーブンに型を入れてください。 </li><li> cap_D（ 図3J）を使用して 、上側にシースを固定するためのポイント5.1から5.6と同じ手順を繰り返します。 </li><li> cap_Cとcap_Dを削除します。 </li><li>中央のシリンダ（ 図3K）を取り外します。 </li></ol>粒状ジャミング膜の作製6 <ol><li>プラスチックグラスに液体ラテックスの5グラムを注ぎます。 </li><li>表面まで液体ラテックス内側の膜（ 図2に示されている最後のピース）のためにシリンダーを浸し完全に覆われています。 </li><li> 20分間のボンネットの下にそれが乾燥してみましょう。 </li><li>ポイント6.2と6.3を繰り返します。 </li><li>金型からの膜を除去します。 </li></ol>粒状ジャミング膜の7.挿入<ol><li>所望の長さ（例えば300ミリメートル）にチューブ（直径2 mm）をカットします。 </li><li>約100mm 2のナイロン組織の二乗の部分をカットし、プラスチックパラフィンフィルムや瞬間接着剤を使用して、この組織をチューブの一端を閉じます。 </li><li>コー​​ヒー粉末の4グラムを計量し、膜を埋めます。 </li><li>満たされた膜の内側チューブ（フィルタが付いている）を挿入し、プラスチックパラフィンフィルムを使用してチューブの周囲にそれを修正。 </li><li> （膜がより堅くなり）チューブの反対側に真空を適用します。 </li><li> siliconicモジュール（ 図3リットル ）の空の中央チャネルの内側の膜を挿入します。 </li><li>シリコーンモジュールに硬化膜の端部を接着。 </li><li>トップの周りのリングを閉じますモジュール（ 図3メートル ）の側面。 </li><li>表面を平らにするためにリングにシリコンの2グラムを注ぎます。 </li><li>フードの下、60℃でオーブンでシリコーンドライをしてみましょう。 </li><li>リングを取り外します。 </li><li>ポイント底辺のための7.11から7.8（ 図3N）から繰り返します。 </li></ol>

<ol>
	<li>Scott, D. J., 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=Completely+transvaginal+NOTES+cholecystectomy+using+magnetically+anchored+instruments.">Completely transvaginal NOTES cholecystectomy using magnetically anchored instruments.</a> Surgical Endoscopy. 21, 2308-2316 (2007).</li><li>Vitiello, V., Lee, S., Cundy, T., Yang, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Emerging+Robotic+Platforms+for+Minimally+Invasive+Surgery.">Emerging Robotic Platforms for Minimally Invasive Surgery.</a> IEEE Reviews in Biomedical Engineering. 6, 111-126 (2013).</li><li>Vyas, L., Aquino, D., Kuo, C. -. H., Dai, J. S., Dasgupta, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Flexible+Robotics.">Flexible Robotics.</a> BJU International. 107, 187-189 (2011).</li><li>Degani, A., Choset, H., Wolf, A., Zenati, M. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Highly+articulated+robotic+probe+for+minimally+invasive+surgery.">Highly articulated robotic probe for minimally invasive surgery.</a> Proceedings of IEEE International Conference on Robotics and Automation. , 4167-4172 (2006).</li><li>Bajo, A., Dharamsi, L. M., Netterville, J. L., Garrett, C. G., Simaan, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Robotic-assisted+micro-surgery+of+the+throat:+The+trans-nasal+approach.">Robotic-assisted micro-surgery of the throat: The trans-nasal approach.</a> , 232-238 (2013).</li><li>Burgner, J., Swaney, P. J., Lathrop, R. A., Weaver, K. D., Webster, R. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Debulking+From+Within:+A+Robotic+Steerable+Cannula+for+Intracerebral+Hemorrhage+Evacuation.">Debulking From Within: A Robotic Steerable Cannula for Intracerebral Hemorrhage Evacuation.</a> IEEE Transactions on Biomedical Engineering. 60, 2567-2575 (2013).</li><li>Tortora, G., Ranzani, T., De Falco, I., Dario, P., Menciassi, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Miniature+Robot+for+Retraction+Tasks+under+Vision+Assistance+in+Minimally+Invasive+Surgery.">A Miniature Robot for Retraction Tasks under Vision Assistance in Minimally Invasive Surgery.</a> Robotics. 3, 70-82 (2014).</li><li>Laschi, C., Cianchetti, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Soft+Robotics:+new+perspectives+for+robot+bodyware+and+control.">Soft Robotics: new perspectives for robot bodyware and control.</a> Frontiers in Bioengineering and Biotechnology. 2, (2014).</li><li>Loeve, A., Breedveld, P., Dankelman, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Scopes+too+flexible...and+too+stiff.">Scopes too flexible...and too stiff.</a> Pulse, IEEE. 1, 26-41 (2010).</li><li>Cianchetti, M., Follador, M., Mazzolai, B., Dario, P., Laschi, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Design+and+development+of+a+soft+robotic+octopus+arm+exploiting+embodied+intelligence.">Design and development of a soft robotic octopus arm exploiting embodied intelligence.</a> , 5271-5276 (2012).</li><li>Smith, K., Kier, W. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Trunks,+tongues,+and+tentacles:+Moving+with+skeletons+of+muscle.">Trunks, tongues, and tentacles: Moving with skeletons of muscle.</a> American Scientist. 77, 28-35 (1989).</li><li>Walker, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Some+issues+in+creating+&#8220;invertebrate&#8221;+robots.">Some issues in creating &#8220;invertebrate&#8221; robots.</a> , (2000).</li><li>McMahan, W., Jones, B., Walker, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Design+and+implementation+of+a+multi-section+continuum+robot:+Air-octor.">Design and implementation of a multi-section continuum robot: Air-octor.</a> IEEE/RSJ International Conference on Intelligent Robots and Systems. , 2578-2585 (2005).</li><li>Laschi, C., Mazzolai, B., Cianchetti, M., Margheri, L., Follador, M., Dario, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Soft+Robot+Arm+Inspired+by+the+Octopus.">A Soft Robot Arm Inspired by the Octopus.</a> Advanced Robotics (Special Issue on Soft Robotics). 26, 709-727 (2012).</li><li>Chianchetti, 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=Soft+robotics+technologies+to+address+shortcomings+in+today&#8217;s+minimally+invasive+surgery:+the+STIFF-FLOP+approach.">Soft robotics technologies to address shortcomings in today&#8217;s minimally invasive surgery: the STIFF-FLOP approach.</a> Soft Robotics. 1, 122-131 (2014).</li><li>Cheng, N. G., 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=Design+and+Analysis+of+a+Robust,+Low-cost,+Highly+Articulated+manipulator+enabled+by+jamming+of+granular+media.">Design and Analysis of a Robust, Low-cost, Highly Articulated manipulator enabled by jamming of granular media.</a> , 4328-4333 (2012).</li><li>Cianchetti, M., Ranzani, T., Gerboni, G., De Falco, I., Laschi, C., Menciassi, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=STIFF-FLOP+Surgical+Manipulator:+mechanical+design+and+experimental+characterization+of+the+single+module.">STIFF-FLOP Surgical Manipulator: mechanical design and experimental characterization of the single module.</a> Proceedings of IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS. , 3576-3581 (2013).</li><li>De Falco, I., Cianchetti, M., Menciassi, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+soft+and+controllable+stiffness+manipulator+for+minimally+invasive+surgery:+preliminary+characterization+of+the+modular+design).">A soft and controllable stiffness manipulator for minimally invasive surgery: preliminary characterization of the modular design).</a> Proceedings of 36th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC). , (2014).</li><li>De Falco, I., Cianchetti, M., Menciassi, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=STIFF-FLOP+surgical+manipulator:+design+and+preliminary+motion+evaluation).">STIFF-FLOP surgical manipulator: design and preliminary motion evaluation).</a> Proceedings of 4th WorkShop on Computer/Robot Assisted Surgery (CRAS). , 131-134 (2014).</li></ol>

The authors have nothing to disclose.

The technique described in this protocol enables the fabrication of a pneumatically actuated soft unit usable for modular compliant structures. Thanks to the design of the molds and their simple assembly, it is possible to fabricate one complete module in about 4 hours with 7 main steps. The process of fabrication involves specific materials, which are easily available, and work should be carried out under a fume hood. An external set up including air valves, air compressor and vacuum pump is necessary to activate the mo...

医療分野における最近の傾向は、外科手術の侵襲性の低減を推進しています。低侵襲手術（MIS）が正常に腹部の操作のために、ここ数年で改善されました。 MIS手順は腹壁上に配置された四、五アクセスポイント（トロカール）を介して導入されたツールの使用に基づいています。トロカールの数を減らすために、器具は、シングルポート腹腔鏡（SPL）または自然開口腔的内視鏡手術（NOTES）1を挿入することができます。これらの手順は、外部見える傷を防ぐが、手術を実行する際に臨床医のための難しさを増加させます。この制限は、アクセスの減少したポイントにし、回避または臓器2、3の周囲を通過することができない楽器の剛性及び半剛性の性質のために主にある。敏捷および運動性は関節型とハイパー冗長使用して改善することができますより広い、より複雑な作業領域をカバーすることができるロボット、目私たちは、体内の特定のターゲットをより簡単に4、5、6に到達することにし、7必要な後退システムとして動作することが可能となります。柔軟マニピュレータは、このように、従来のツールでより安全に接触すること、組織のコンプライアンスを向上させることができます。 しかし、これらのマニピュレータは、多くの場合、目標が達成される安定性を欠いており、一般的に、彼らは周囲の組織8との接触を制御することはできません9。研究は、このようなタコのアーム10と象のトランク11のような生物学的構造、上、最近のデザインにインスピレーションを与えてきましたフリーダム（自由度）の程度の冗長数、および制御可能な剛性12と、柔軟に変形可能と準拠のマニピュレータ。デバイスのこれらの種類は、受動的なバネ、 ​​スマート材料、空気圧要素、または腱13、14、15を使用しています。一般的に、ソフトで柔軟性のある材料で製作マニピュレータは、大きな力が発生するのを保証するものではありません。 T彼STIFFプ（手術用剛性制御柔軟で学習可能なマニピュレータ）はマニピュレータは最近、タコの機能に触発NOTESとSPLのための新規な外科用デバイスとして提示されています。以前のソフトマニピュレータの限界を克服するためには、高い器用さ、高い力制御剛性16と同様にソフトボディを有しています。 マニピュレータのアーキテクチャはモジュール方式に基づいています。同じ構造と機能を持つ複数のユニットは、一体化されています。単一のユニットは、 図1に示されている。これは、マルチ加工によって得られるエラストマー性シリンダーに基づいています。金型部品の組立工程や鋳造プロセスは、3つの空室（流体作動のため）と埋め込 ​​まれる（粒状のジャムベース機構 18 を収容するための）1の中空中央チャネル17を有効にします 。チャンバはそのように、120°に配置されていますIR組み合わせたインフレ率は、無指向性運動と伸びを生成します。また、外部編組シースは、このように（曲げ及び伸び）モジュールモーションで室の作動の効果を最適化し、加圧されたときに、流体室の外側に半径方向拡張を制限するために、外部に配置されます。 中央チャネルは、粒状材料を充填した外膜からなる円筒デバイスを収容します。真空圧が印加されると、それは、モジュール全体の特性に影響を与える硬化を引き起こし、その弾性特性が変化します。 運動及び剛性性能を補強チャネル内の真空を活性化するためのチャンバと、1つの真空ポンプを作動させるための空気圧縮機と3つの圧力弁を含む、外部の設定によって制御されます。直感的なユーザーインターフェイスは、モジュール内の作動および真空圧力の制御を可能にします。 本稿ではfabricatioの詳細このマニピュレータとレポートの基本的な運動能力の最も重要な結果の一つのモジュールのn個のプロセス。デバイスのモジュールの性質を考えると、ただ1つのモジュールの製造および性能の評価はまた、結果を拡張すると、二つ以上のモジュールを統合したマルチモジュールマニピュレータの基本的な挙動を予測することができます。

<table border="0">
	<tbody>
		<tr>
			<td>Ecoflex 00-50 Trial Kit</td>
			<td>SmoothOn</td>
			<td></td>
			<td>Used for the fabrication of the soft unit, combining equal amounts of liquid parts A (the base) and B (the catalyst)</td>
		</tr>
		<tr>
			<td>Latex</td>
			<td>Antichit&#224; Belsito</td>
			<td></td>
			<td>Used for the fabrication of the granular jamming membrane</td>
		</tr>
		<tr>
			<td>Peroxide-Cured Silicone Tubing</td>
			<td>Cole Parmer</td>
			<td>T-06411-59</td>
			<td>Used for actuating the chambers and applying vacuum</td>
		</tr>
		<tr>
			<td>PET expandable braided sleeving</td>
			<td>RS</td>
			<td>408-249</td>
			<td>Used for the fabrication of the external braided sheath</td>
		</tr>
		<tr>
			<td>Silicone Rubber</td>
			<td>Momentive</td>
			<td>127374</td>
			<td>Used to fix the actuation tubes to the module</td>
		</tr>
		<tr>
			<td>Parafilm</td>
			<td>Cole Parmer</td>
			<td>EW-06720-40</td>
			<td>Used to fix the latex membrane to the vacuum tube</td>
		</tr>
		<tr>
			<td>Fume hood Secuflow</td>
			<td>Groupe Waldner</td>
			<td></td>
			<td>Working space</td>
		</tr>
		<tr>
			<td>Precision scale</td>
			<td>KERN EW</td>
			<td></td>
			<td>Used to weight silicone, latex and coffee powder</td>
		</tr>
		<tr>
			<td>Oven/degasser</td>
			<td>Heraeus</td>
			<td></td>
			<td>Used to degass the silicone and reduce its cure time</td>
		</tr>
		<tr>
			<td>Vacuum pump</td>
			<td>DVP Vacuum Technology</td>
			<td></td>
			<td>Used to apply vacuum to the latex membrane</td>
		</tr>
	</tbody>
</table>

design and fabrication of an elastomeric unit for soft modular robots in minimally invasive surgery

近年では、ソフトロボット技術が原因で構造化されていない環境では、その本質的に安全な相互作用のために医療分野への関心を高めること喚起しています。同時に、新しい手順および技術は、外科手術の侵襲性を低減するために開発されてきました。低侵襲手術（MIS）が正常腹部の介入のために使用されている、しかし、標準的なMIS手順は、主に臨床医の器用さを制限する剛性または半剛性のツールに基づいています。本稿では、MISのための柔らかく、高い器用なマニピュレータを提供します。マニピュレータは、タコの腕の生物学的機能に触発された、およびモジュール方式で設計されています。各モジュールは、複数のモジュールが統合されているときにこのように高い器用さと汎用性を実現し、同じ機能特性を提供します。論文は、キャスティによって作製された単一ユニットの開発のために必要な設計、製造プロセスや材料の内訳を特定の型の内部グラムシリコーン。結果は、伸びとユニットの無指向性の屈曲を可能にする3つの柔軟性空気圧アクチュエータを含むエラストマー気筒で構成されています。外部編組シースは、モジュールの動作を改善します。各モジュールの中央には粒状のジャムベースのメ​​カニズムは、タスク中の構造の剛性を変化させます。テストモジュール120°まで曲げ、初期長さの66％まで伸長することが可能であることを示しています。モジュールは、47 Nの最大の力を発生し、その剛性は36％まで増加させることができます。

プロトコールに記載製造の様々な段階は、 図3に示されています。 手法の有効性および最終プロトタイプの成果を評価するために、モジュールは、異なる作業条件下で試験しました。外部セットアップは、モジュールの作動と剛性の両方を制御することができます。これは3つのバルブを作動させるエアコンプレッサとを含みます。彼らは、チャンバー内に統...

Watch this Scientific Journal Video about Design and Fabrication of an Elastomeric Unit for Soft Modular Robots in Minimally Invasive Surgery at JoVE.com

Design and Fabrication of an Elastomeric Unit for Soft Modular Robots in Minimally Invasive Surgery

This paper describes the design and fabrication of a soft unit for surgical manipulators. The base module includes three flexible fluidic actuators to achieve omnidirectional bending and elongation, and a granular jamming-based mechanism to enable stiffness control. A complete mechanical characterization is also reported.

低侵襲手術でのソフトモジュラーロボットのエラストマーユニットの設計と製作

In recent years, soft robotics technologies have aroused increasing interest in the medical field due to their intrinsically safe interaction in ...

design-fabrication-an-elastomeric-unit-for-soft-modular-robots

Research

JoVE Journal

Bioengineering

8.9K ビュー.  Scuola Superiore Sant'Anna. This paper describes the design and fabrication of a soft unit for surgical manipulators. The base module includes three flexible fluidic actuators to achieve omnidirectional bending and elongation, and a granular jamming-based mechanism to enable stiffness control. A complete mechanical characterization is also reported. 

ビデオ: Design and Fabrication of an Elastomeric Unit for Soft Modular Robots in Minimally Invasive Surgery

Elastomeric PGS Scaffolds in Arterial Tissue Engineering

Cardiovascular disease is one of the leading cause of mortality in the US and especially, coronary artery disease increases with an aging population and increasing obesity1. Currently, bypass surgery using autologous vessels, allografts, and synthetic grafts are known as a commonly used for arterial substitutes2. However, these grafts have limited applications when an inner diameter of arteries is less than 6 mm due to low availability, thrombotic complications, compliance mismatch, and late intimal hyperplasia3,4. To overcome these limitations, tissue engineering has been successfully applied as a promising alternative to develop small-diameter arterial constructs that are nonthrombogenic, robust, and compliant. Several previous studies have developed small-diameter arterial constructs with tri-lamellar structure, excellent mechanical properties and burst pressure comparable to native arteries5,6. While high tensile strength and burst pressure by increasing collagen production from a rigid material or cell sheet scaffold, these constructs still had low elastin production and compliance, which is a major problem to cause graft failure after implantation. Considering these issues, we hypothesized that an elastometric biomaterial combined with mechanical conditioning would provide elasticity and conduct mechanical signals more efficiently to vascular cells, which increase extracellular matrix production and support cellular orientation.
The objective of this report is to introduce a fabrication technique of porous tubular scaffolds and a dynamic mechanical conditioning for applying them to arterial tissue engineering. We used a biodegradable elastomer, poly (glycerol sebacate) (PGS)7 for fabricating porous tubular scaffolds from the salt fusion method. Adult primary baboon smooth muscle cells (SMCs) were seeded on the lumen of scaffolds, which cultured in our designed pulsatile flow bioreactor for 3 weeks. PGS scaffolds had consistent thickness and randomly distributed macro- and micro-pores. Mechanical conditioning from pulsatile flow bioreactor supported SMC orientation and enhanced ECM production in scaffolds. These results suggest that elastomeric scaffolds and mechanical conditioning of bioreactor culture may be a promising method for arterial tissue engineering.

Elastomeric PGS scaffolds with vascular smooth muscle cells cultured in a pulsatile flow bioreactor may lead to promising small-diameter arterial constructs with native ECM production in a relatively short culture period.

動脈組織工学におけるエラストマーのPGSの足場

Cardiovascular disease is one of the leading cause of mortality in the US and especially, coronary artery disease increases with an aging population and ...

生物工学

Polymeric Microneedle Array Fabrication by Photolithography

This manuscript describes the fabrication of polymeric microneedle (MN) arrays by photolithography. It involves a simple mold-free process by using a photomask consisting of embedded micro-lenses. Embedded micro-lenses were found to influence MN geometry (sharpness). Robust MN arrays with tip diameters ranging between 41.5 &#181;m &#177; 8.4 &#181;m and 71.6 &#181;m &#177; 13.7 &#181;m, with two different lengths (1,336 &#181;m &#177; 193 &#181;m and 957 &#181;m &#177; 171 &#181;m) were fabricated. These MN arrays may provide potential applications in delivery of low molecular and macromolecular therapeutic agents through skin.

Here, we present a protocol describing a mold-free fabrication process of the polymeric microneedles by photolithography.

フォトリソグラフィ法により高分子マイクロニードルアレイの作製

This manuscript describes the fabrication of polymeric microneedle (MN) arrays by photolithography. It involves a simple mold-free process by using a ...

Rod-based Fabrication of Customizable Soft Robotic Pneumatic Gripper Devices for Delicate Tissue Manipulation

Soft compliant gripping is essential in delicate surgical manipulation for minimizing the risk of tissue grip damage caused by high stress concentrations at the point of contact. It can be achieved by complementing traditional rigid grippers with soft robotic pneumatic gripper devices. This manuscript describes a rod-based approach that combined both 3D-printing and a modified soft lithography technique to fabricate the soft pneumatic gripper. In brief, the pneumatic featureless mold with chamber component is 3D-printed and the rods were used to create the pneumatic channels that connect to the chamber. This protocol eliminates the risk of channels occluding during the sealing process and the need for external air source or related control circuit. The soft gripper consists of a chamber filled with air, and one or more gripper arms with a pneumatic channel in each arm connected to the chamber. The pneumatic channel is positioned close to the outer wall to create different stiffness in the gripper arm. Upon compression of the chamber which generates pressure on the pneumatic channel, the gripper arm will bend inward to form a close grip posture because the outer wall area is more compliant. The soft gripper can be inserted into a 3D-printed handling tool with two different control modes for chamber compression: manual gripper mode with a movable piston, and robotic gripper mode with a linear actuator. The double-arm gripper with two actuatable arms was able to pick up objects of sizes up to 2 mm and yet generate lower compressive forces as compared to elastomer-coated and non-coated rigid grippers. The feasibility of having other designs, such as single-arm or hook gripper, was also demonstrated, which further highlighted the customizability of the soft gripper device, and it's potential to be used in delicate surgical manipulation to reduce the risk of tissue grip damage.

This protocol describes a rod-based approach, combining 3D-printing and soft lithography techniques for fabricating the soft gripper devices. This approach eliminates the need for an external air source by incorporating a chamber component and reduces the chance of occlusion during the sealing process, particularly for miniaturized pneumatic channels.

繊細な組織操作のためのカスタマイズ可能なソフトロボット空気圧グリッパ装置のロッドベースの試作

Soft compliant gripping is essential in delicate surgical manipulation for minimizing the risk of tissue grip damage caused by high stress concentrations ...

Automated Robotic Liquid Handling Assembly of Modular DNA Devices

Recent advances in modular DNA assembly techniques have enabled synthetic biologists to test significantly more of the available &#34;design space&#34; represented by &#34;devices&#34; created as combinations of individual genetic components. However, manual assembly of such large numbers of devices is time-intensive, error-prone, and costly. The increasing sophistication and scale of synthetic biology research necessitates an efficient, reproducible way to accommodate large-scale, complex, and high throughput device construction.
Here, a DNA assembly protocol using the Type-IIS restriction endonuclease based Modular Cloning (MoClo) technique is automated on two liquid-handling robotic platforms. Automated liquid-handling robots require careful, often times tedious optimization of pipetting parameters for liquids of different viscosities (e.g. enzymes, DNA, water, buffers), as well as explicit programming to ensure correct aspiration and dispensing of DNA parts and reagents. This makes manual script writing for complex assemblies just as problematic as manual DNA assembly, and necessitates a software tool that can automate script generation. To this end, we have developed a web-based software tool, http://mocloassembly.com, for generating combinatorial DNA device libraries from basic DNA parts uploaded as Genbank files. We provide access to the tool, and an export file from our liquid handler software which includes optimized liquid classes, labware parameters, and deck layout. All DNA parts used are available through Addgene, and their digital maps can be accessed via the Boston University BDC ICE Registry. Together, these elements provide a foundation for other organizations to automate modular cloning experiments and similar protocols.
The automated DNA assembly workflow presented here enables the repeatable, automated, high-throughput production of DNA devices, and reduces the risk of human error arising from repetitive manual pipetting. Sequencing data show the automated DNA assembly reactions generated from this workflow are ~95% correct and require as little as 4% as much hands-on time, compared to manual reaction preparation.

Here, an automated workflow to perform modular DNA &#34;device&#34; assembly using a modular cloning DNA assembly method on liquid-handling robots is presented. The protocol uses an intuitive software tool for generating liquid handler picklists for combinatorial DNA device library generation, which we demonstrate using two liquid handling platforms.

モジュラー DNA デバイスの液体ハンドリング アセンブリを自動化

Recent advances in modular DNA assembly techniques have enabled synthetic biologists to test significantly more of the available &#34;design space&#34; ...

Biomechanical Characterization of Human Soft Tissues Using Indentation and Tensile Testing

Regenerative medicine aims to engineer materials to replace or restore damaged or diseased organs. The mechanical properties of such materials should mimic the human tissues they are aiming to replace; to provide the required anatomical shape, the materials must be able to sustain the mechanical forces they will experience when implanted at the defect site. Although the mechanical properties of tissue-engineered scaffolds are of great importance, many human tissues that undergo restoration with engineered materials have not been fully biomechanically characterized. Several compressive and tensile protocols are reported for evaluating materials, but with large variability it is difficult to compare results between studies. Further complicating the studies is the often destructive nature of mechanical testing. Whilst an understanding of tissue failure is important, it is also important to have knowledge of the elastic and viscoelastic properties under more physiological loading conditions.
This report aims to provide a minimally destructive protocol to evaluate the compressive and tensile properties of human soft tissues. As examples of this technique, the tensile testing of skin and the compressive testing of cartilage are described. These protocols can also be directly applied to synthetic materials to ensure that the mechanical properties are similar to the native tissue. Protocols to assess the mechanical properties of human native tissue will allow a benchmark by which to create suitable tissue-engineered substitutes.

Tissue biomechanics is important for maintaining cell shape and function and for determining phenotype. This report demonstrates non-destructive mechanical protocols for characterizing elastic and viscoelastic properties of human soft tissues, which can be directly applied to tissue-engineered substrates to allow a close matching of engineered materials to native tissue.

インデントと引張試験を用いたヒト軟部組織の生体力学的特性評価

Regenerative medicine aims to engineer materials to replace or restore damaged or diseased organs. The mechanical properties of such materials should ...

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 ...

Bioinspired Soft Robot with Incorporated Microelectrodes

Bioinspired soft robotic systems that mimic living organisms using engineered muscle tissue and biomaterials are revolutionizing the current biorobotics paradigm, especially in biomedical research. Recreating artificial life-like actuation dynamics is crucial for a soft-robotic system. However, the precise control and tuning of actuation behavior still represents one of the main challenges of modern soft robotic systems. This method describes a low-cost, highly scalable, and easy-to-use procedure to fabricate an electrically controllable soft robot with life-like movements that is activated and controlled by the contraction of cardiac muscle tissue on a micropatterned sting ray-like hydrogel scaffold. The use of soft photolithography methods makes it possible to successfully integrate multiple components in the soft robotic system, including micropatterned hydrogel-based scaffolds with carbon nanotubes (CNTs) embedded gelatin methacryloyl (CNT-GelMA), poly(ethylene glycol) diacrylate (PEGDA), flexible gold (Au) microelectrodes, and cardiac muscle tissue. In particular, the hydrogels alignment and micropattern are designed to mimic the muscle and cartilage structure of the sting ray. The electrically conductive CNT-GelMA hydrogel acts as a cell scaffold that improves the maturation and contraction behavior of cardiomyocytes, while the mechanically robust PEGDA hydrogel provides structural cartilage-like support to the whole soft robot. To overcome the hard and brittle nature of metal-based microelectrodes, we designed a serpentine pattern that has high flexibility and can avoid hampering the beating dynamics of cardiomyocytes. The incorporated flexible Au microelectrodes provide electrical stimulation across the soft robot, making it easier to control the contraction behavior of cardiac tissue.

A bioinspired scaffold is fabricated by a soft photolithography technique using mechanically robust and electrically conductive hydrogels. The micropatterned hydrogels provide directional cardiomyocyte cell alignment, resulting in a tailored direction of actuation. Flexible microelectrodes are also integrated into the scaffold to bring electrical controllability for a self-actuating cardiac tissue.

生体にインスパイアされたマイクロ電極を用いたソフトロボット

Bioinspired soft robotic systems that mimic living organisms using engineered muscle tissue and biomaterials are revolutionizing the current biorobotics ...

Simple, Affordable, and Modular Patterning of Cells using DNA

The relative positioning of cells is a key feature of the microenvironment that organizes cell-cell interactions. To study the interactions between cells of the same or different type, micropatterning techniques have proved useful. DNA Programmed Assembly of Cells (DPAC) is a micropatterning technique that targets the adhesion of cells to a substrate or other cells using DNA hybridization. The most basic operations in DPAC begin with decorating cell membranes with lipid-modified oligonucleotides, then flowing them over a substrate that has been patterned with complementary DNA sequences. Cells adhere selectively to the substrate only where they find a complementary DNA sequence. Non-adherent cells are washed away, revealing a pattern of adherent cells. Additional operations include further rounds of cell-substrate or cell-cell adhesion, as well as transferring the patterns formed by DPAC to an embedding hydrogel for long-term culture. Previously, methods for patterning oligonucleotides on surfaces and decorating cells with DNA sequences required specialized equipment and custom DNA synthesis, respectively. We report an updated version of the protocol, utilizing an inexpensive benchtop photolithography setup and commercially available cholesterol modified oligonucleotides (CMOs) deployed using a modular format. CMO-labeled cells adhere with high efficiency to DNA-patterned substrates. This approach can be used to pattern multiple cell types at once with high precision and to create arrays of microtissues embedded within an extracellular matrix. Advantages of this method include its high resolution, ability to embed cells into a three-dimensional microenvironment without disrupting the micropattern, and flexibility in patterning any cell type.

Here we present a protocol to micropattern cells at single-cell resolution using DNA-programmed adhesion. This protocol uses a benchtop photolithography platform to create patterns of DNA oligonucleotides on a glass slide and then labels cell membranes with commercially available complementary oligonucleotides. Hybridization of the oligos results in programmed cell adhesion.

DNAを用いた細胞のシンプル、手頃な価格、モジュール式パターニング

The relative positioning of cells is a key feature of the microenvironment that organizes cell-cell interactions. To study the interactions between cells ...

Voxel Printing Anatomy: Design and Fabrication of Realistic, Presurgical Planning Models through Bitmap Printing

Most applications of 3-dimensional (3D) printing for presurgical planning have been limited to bony structures and simple morphological descriptions of complex organs due to the fundamental limitations in accuracy, quality, and efficiency of the current modeling paradigm. This has largely ignored the soft tissue critical to most surgical specialties where the interior of an object matters and anatomical boundaries transition gradually. Therefore, the needs of the biomedical industry to replicate human tissue, which displays multiple scales of organization and varying material distributions, necessitate new forms of representation. 
Presented here is a novel technique to create 3D models directly from medical images, which are superior in spatial and contrast resolution to current 3D modeling methods and contain previously unachievable spatial fidelity and soft tissue differentiation. Also presented are empirical measurements of novel, additively manufactured composites that span the gamut of material stiffnesses seen in soft biological tissues from MRI and CT. These unique volumetric design and printing methods allow for deterministic and continuous adjustment of material stiffness and color. This capability enables an entirely new application of additive manufacturing to presurgical planning: mechanical realism. As a natural complement to existing models that provide appearance matching, these new models also allow medical professionals to "feel" the spatially varying material properties of a tissue simulant-a critical addition to a field in which tactile sensation plays a key role.

This method demonstrates a voxel-based 3D printing workflow, which prints directly from medical images with exact spatial fidelity and spatial/contrast resolution. This enables the precise, graduated control of material distributions through morphologically complex, graduated materials correlated to radiodensity without loss or alteration of data.

ボクセル印刷の解剖学:ビットマップ印刷による現実的な手術前計画モデルの設計と製造

Most applications of 3-dimensional (3D) printing for presurgical planning have been limited to bony structures and simple morphological descriptions of ...

Synthesis of Strong Adhesive Hydrogel, Gelatin O-Nitrosobenzaldehyde

Adhesive materials have become popular biomaterials in the field of biomedical and tissue engineering. In our previous work, we presented a new material - gelatin o-nitrosobenzaldehyde (gelatin-NB) - which is mainly used for tissue regeneration and has been validated in animal models of corneal injury and inflammatory bowel disease. This is a novel hydrogel formed by modifying biological gelatin with o-nitrosobenzaldehyde (NB). Gelatin-NB was synthesized by activating the carboxyl group of NB-COOH and reacting with gelatin through 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC) and N-hydroxysuccinimide (NHS). The obtained compound was purified to generate the final product, which can be stably stored for at least 18 months. NB has a strong adhesion to -NH2 on the tissue, which can form many C = N bonds, thus increasing the adhesion of gelatin-NB to the tissue interface. The preparation process comprises steps for the synthesis of the NB-COOH group, modification of the group, synthesis of gelatin-NB, and purification of the compound. The goal is to describe the specific synthesis process of gelatin-NB in detail and to demonstrate the application of gelatin-NB to damage repair. Moreover, the protocol is presented to further strengthen and expand the nature of the material produced by the scientific community for more applicable scenarios.

The protocol presented here shows the synthesis of a strong adhesive hydrogel gelatin o-nitrosobenzaldehyde (gelatin-NB). Gelatin-NB has rapid and efficient tissue adhesion ability, which can form a strong physical barrier to protect wound surfaces, so it is expected to be applied to the field of injury repair biotechnology.

強接着性ハイドロゲルゼラチンO-ニトロソベンズアルデヒドの合成

Adhesive materials have become popular biomaterials in the field of biomedical and tissue engineering. In our previous work, we presented a new material - ...