著者はLJRフォスターに国立保健オーストラリアの医学研究評議会（NHMRC＃1000674）からの助成金を認めている。

1。 SurgiLux溶液の調製<ol><li>きれいなガラスビーカーに脱イオン水を用いて酢酸の2％（v / v）の溶液を調製し、汚染を避けるために、層流フードを使用しています。 </li><li>発色団の0.02％（w / v）を秤量し、滅菌エッペンドルフチュー​​ブに、ICG、インドシアニングリーン、チューブはどんな光の侵入を防ぐために、銀ホイルに包まれていることを確認します。 </li><li>きれいで、使い捨てピペットを用いて、色素を溶解そっと振るとホイルに包まれた保つためにチューブに希酢酸溶液約1mlを転送します。 </li><li>ビーカーの中に可溶化されたICGを移し、無菌のマグネチックスターラーを追加する前に、キトサン粉末を2％（w / v）を追加します。 </li><li>パラフィルムでビーカーをカバーした後、層流フード内で室温で72時間約125 rpmで内容物を混合する前に、銀ホイルで包む。 </li><li> 4℃で15分間、15,000×gでクリーンな遠心チューブと遠心分離機に内容を転送℃の任意particulaを削除するteの問題。 </li><li>慎重にきれいなガラスビーカーに緑SurgiLuxソリューションを譲渡、溶液の粘度を高めるために12時間、冷蔵庫で保管する前に、銀ホイルで包むその後パラフィルムを使用してカバーしています。 </li></ol> 2。 SurgiLuxフィルムの鋳造<ol><li>無菌の注射器を用いて、95ミリメートル径のクリーン、ペトリ皿に冷たいSurgiLuxの溶液8mlを分配、ゆっくりと溶液によって完全なカバレッジを確保するためにプレートを傾けてください。鋳造領域に溶液体積の比を変化させること、膜厚の制御を可能にし、 図1を参照してください。 </li><li>無菌針の先端を使用して溶液中で目に見える気泡を除去する。残留ミクロンサイズの気泡を除去するために冷蔵庫で銀箔と所定の位置に皿をカバーしています。 </li><li> 20分は慎重に冷蔵庫からシャーレを削除した後、層流フード内の場所は、銀ホイルで覆い、3週間蒸発するソリューションを残す。 </li><li> CO後にmplete蒸発、離れる皿表面からフィルム &#39;ピール&#39;優しくスコアシャーレ内の明確な緑SurgiLuxフィルムの外側の縁と。 </li><li> SurgiLux膜が裂けたり壊すことなく、柔軟かつ容易に操作する必要があります。 </li><li>使用直前まで、乾燥条件下で銀ホイルに包まれたペトリ皿に円形SurgiLuxフィルムを保管してください。 </li></ol> 3。 SurgiLux接着フィルムのレーザー活性化<ol><li>レーザー活性化のプロセスを説明するために、我々はこのような幅15mmと20mmの長さのサイズにカットステーキなどウシ組織片を使用します。 10ミリメートルで15の2個を生成するために、数字の10外科用ブレードを使用して、直線で組織を切開する。 </li><li>おおよそそれらの縁が触れなく重なり、そして綿棒やガーゼを使用しているように、組織の2つの部分は、優しく余分な体液を吸収する。 </li><li>次に、SurgiLux膜7×9 mmの部分をカットし、慎重に二分されたP間のフィルム縦に置く組織の電子通信学会論文誌、その後乾いた綿棒で軽く下に押します。 </li><li> SurgiLuxフィルムが120 mWの設定で赤外ダイオードレーザーを使用して活性化される。これはクラスIIIbのレーザーであるため、適切な安全対策を全職員に対して適切な安全メガネの使用を含めて、取られるべきである。 </li><li>隅から、120 mWで設定赤外レーザーと直径1mmのビームスポットサイズとSurgiLuxを照射します。毎秒約1ミリメートルの割合で緑の膜上のビームスポットを渡します。照射工程を2回繰り返します。 </li></ol> 4。修理の強さ<ol><li>慎重に引張試験器のクランプに組織の両端を固定します。我々は、50ニュートンのロードセルでインストロンMini55システムを使用しています。破断時の最大荷重、引張強さ、および拡張がBluehillコンピュータソフトウェア（米国）を用いて計算した。少なくとも10個のサンプルから手段（n = 10）に決定した。 </li><li> &quot;たるみ&quot;を取るその後、完全に独立したSurgiLuxストリップによって一緒に保持された組織の2枚まで、毎秒1ミリメートルの割合で組織片を分離する。 </li></ol>

<ol>
	<li>Kjaergard, H. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Suture+support:+is+it+advantageous.">Suture support: is it advantageous.</a> Am. J. Surg. 182, 15S-20S (2001).</li><li>Lauto, A., Mawad, D., Foster, L. J. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Adhesive+biomaterials+for+tissue+reconstruction.">Adhesive biomaterials for tissue reconstruction.</a> J. Chem. Tech. Biotech. 83, 464-472 (2008).</li><li>Fung, L. C., Mingin, G. C., Massicotte, M., Felsen, D., Poppas, D. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+temperature+on+tissue+thermal+injury+and+wound+strength+after+photochemical+wound+closure.">Effects of temperature on tissue thermal injury and wound strength after photochemical wound closure.</a> Lasers Surg. Med. 25, 285-290 (1999).</li><li>Piribo, <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Glues &amp; Sealants: Industry Background Report. , (2005).</li><li>Lauto, A., Hook, J., Doran, M., Camacho, F., Poole-Warren, L. A., Avolio, A., Foster, L. J. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chitosan+adhesive+for+laser+tissue-welding:+in+vitro+characterisation.">Chitosan adhesive for laser tissue-welding: in vitro characterisation.</a> Lasers Surg. Med. 36, 193-201 (2005).</li><li>Lauto, A., Stoodley, M., Marcel, H., Avolio, A., Sarris, M., McKenzie, G., Sampson, D. D., Foster, L. J. R. <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+and+in+vivo+tissue+repair+with+laser-activated+chitosan+adhesive.">In vitro and in vivo tissue repair with laser-activated chitosan adhesive.</a> Lasers Surg. Med. 39, 19-27 (2007).</li><li>Lauto, A., Foster, L. J. R., Avolio, A., Sampson, D., Raston, C., Sarris, M., McKenzie, G., Stoodley, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sutureless+Nerve+Repair+with+Laser-Activated+Chitosan+Adhesive:+A+Pilot+in+vivo+Study.">Sutureless Nerve Repair with Laser-Activated Chitosan Adhesive: A Pilot in vivo Study.</a> J. Photomed. Laser. Surg. 26 (3), 227-234 (2008).</li><li>Mar&#231;al, H., Badylak, S. F., Sellaro, T. L., Lauto, A., Foster, L. J. R., Mahler, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+coalescence+of+decellularized+tissue+scaffolds,+laser-activated+chitosan+bioadhesive+and+olfactory+ensheathing+cells+for+tissue+repair+and+regeneration+of+the+spinal+cord.">The coalescence of decellularized tissue scaffolds, laser-activated chitosan bioadhesive and olfactory ensheathing cells for tissue repair and regeneration of the spinal cord.</a> Lasers Med. Sci. 23 (1), 96 (2008).</li><li>Foster, L. J. R., Thomson, K., Marcal, H., Butt, J., Watson, S., Wakefield, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+chitosan-vancomycin+composite+biomaterial+as+a+laser+activated+surgical+adhesive+with+regional+antimicrobial+activity.">A chitosan-vancomycin composite biomaterial as a laser activated surgical adhesive with regional antimicrobial activity.</a> Biomacromolecules. 11 (12), 3563-3570 (2010).</li><li>Shahbazi, J., Marcal, H., Watson, S., Wakefield, D., Sarris, M., Foster, L. J. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sutureless+sealing+of+penetrating+corneal+wounds+using+a+laser-activated+thin+film+adhesive.">Sutureless sealing of penetrating corneal wounds using a laser-activated thin film adhesive.</a> Lasers Surg. Med. , .</li><li>Meyers, M. A., Chen, P. -. Y., Lin, A. Y. -. M., Seki, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biological+materials:+Structure+and+mechanical+properties.">Biological materials: Structure and mechanical properties.</a> Prog. Mater. Sci. 53 (1), 1-206 (2008).</li></ol>

特別な利害関係は宣言されません。

キトサンは分子量の様々なとdeactylation度の異なる（DDA）を使って取得できます。キトサンの純度のばらつきがSurgiLux溶液中の微粒子の存在につながる可能性があり、遠心分離は、これらを排除し、透明な緑色の溶液をもたらすべきである使用されています。しかし、ろ過も追加または代替の製造ステップとして使用することができます。どんな材料加工と同様に、例えばキトサンDDAと分子量?...

<table border="1"><tbody><tr><td> 試薬/機器の名称 </td><td> 会社 </td><td> カタログ番号 </td><td> コメント（オプション） </td></tr><tr><td>キトサン</td><td>シグマアルドリッチ</td><td> 448877 </td><td></td></tr><tr><td>インドシアニングリーン</td><td>シグマアルドリッチ</td><td> I2633 </td><td>またCardiogreenとして知られている</td></tr><tr><td>酢酸</td><td>シグマアルドリッチ</td><td> 320099 </td><td></td></tr><tr><td>繊維配達の赤外ダイオードレーザー。 （808 nmで、120 mWで、ビームコア200μm）の</td><td> CNIレーザー</td><td> FC-808 </td><td>可変システム最大5 W電源</td></tr><tr><td>レーザー安全メガネ</td><td> CNIレーザー</td><td> LS-G </td><td></td></tr><tr><td>引張試験装置</td><td>インストロンPty Ltdの</td><td> 5542 </td><td> 50Nのロードセル</td></tr></tbody></table>

a chitosan based, laser activated thin film surgical adhesive, 'surgilux': preparation and demonstration

縫合糸は、その修理強度（〜100 kPa）のおかげで、創傷の閉鎖のための &quot;ゴールド·スタンダード&quot;のまま4000年の古い技術である。しかし、縫合糸が感染の病巣として作用することができると多くの手続きにおいて創傷修復を行うか、または機能的な組織の再生を妨害することはできません。例えば、フィブリン及びシアノアクリレートに基づくものなど1外科接着剤および接着剤は、用縫合糸の代替品として開発されてきたこのような傷の修理。しかし、現在市販されている接着剤はまた、ウイルスやプリオン伝達とフィブリン糊と同様に修理の強度不足から組織毒性及びシアノアクリレート系接着剤のための生体適合性の欠如に至るまで、大きなデメリットがあります。また、現在利用可能な外科用接着剤は、ゲルをベースになる傾向があり、それらのアプリケーションを制限硬化時間を延長したことができます2同様に、 &quot;タンパク質ベースまたはアルブミンゾル架橋メカニズムを容易にするためにUVレーザーを使用することレーザー組 ​​織溶接（LTW）が組織への熱損傷を素因としながら&#39;がDNA損傷につながることができます。3はその欠点や接着剤、LTWもかかわらdersは、取得した創傷閉鎖市場の約30％は、年間50億ドルの過剰であることが報告縫合技術の必要性への重要な証し。4 縫合技術の追求では、柔軟性のある、薄膜、 &#39;SurgiLux &quot;と呼ばれるレーザーで活性化外科用接着剤の開発のための生体材料としてキトサンを利用してきた。この小説の生体接着剤は、FDAが生物医学アプリケーションと様々な製品で承認され、成功裏に使用されている生体材料、フォトニクスのユニークな組み合わせを使用しています。 SurgiLuxは、縫合糸と現在の外科用接着剤（ 表1を参照）に関連付けられているすべての欠点を克服する。 本発表ではSurgiLuxの製作のための比較的単純なプロトコルを報告し、実証そのレーザーの活性化と組織溶接強度。 SurgiLux膜は、架橋と照射により比較的低パワー（120 mW）の赤外線レーザーの代わりに紫外光を使用するなど、このような化学修飾することなく、コラーゲン組織に付着する。キトサンフィルムがコラーゲン（約3 kPa）までの自然が、弱い接着剤の魅力を持っている、キトサンベースSurgiLuxフィルムのレーザー活性化は、過渡熱膨張の結果としてポリマー鎖間の相互作用を介してこの接着の強さを強調している。5は、この&quot;活性化&quot;のプロセスがなければ、SurgiLux膜が容易に除去されます6月9日 SurgiLuxが神経、腸、硬膜や角膜など、様々な組織に、in vitroおよびin vivoの両方でテストされています。すべてのケースでは、優れた生体適合性と照射の結果として無視できる熱損傷を示した。6-10

遠心分離は4-6での貯蔵後の粘度を増加させる透明な緑色の溶液、℃につながる3週間放置した後、ビデオで示したように緑色の溶液は、約20ミクロンの厚さで透明な緑色SurgiLuxフィルムに変換され、容易に柔軟です。 組織へのSurgiLux膜結合レーザー照射により、。これは、組織が ​​レーザービームがフィルム（ 図2）の上を通過するように収縮するように表?...

Watch this Scientific Journal Video about A Chitosan Based, Laser Activated Thin Film Surgical Adhesive, 'SurgiLux': Preparation and Demonstration at JoVE.com

A Chitosan Based, Laser Activated Thin Film Surgical Adhesive, &#039;SurgiLux&#039;: Preparation and Demonstration

小説の製造、FDAが承認した成分からフレキシブル薄膜外科用接着剤、キトサンおよびインドシアニングリーンが記載されている。低出力の赤外線レーザーで簡単なアクティベーションプロセスによりコラーゲン組織にこの接着剤の接着性を示す。

キトサンベース、レーザー活性薄膜外科用接着剤、 &#39;SurgiLux&#39;：準備とデモ

Sutures are a 4,000 year old technology that remain the 'gold-standard' for wound closure by virtue of their repair strength (~100 KPa). However, sutures ...

a-chitosan-based-laser-activated-thin-film-surgical-adhesive-surgilux

Research

JoVE Journal

Bioengineering

A Chitosan Based, Laser Activated Thin Film Surgical Adhesive, 'SurgiLux': Preparation and Demonstration

13.1K ビュー.  University of New South Wales. 小説の製造、FDAが承認した成分からフレキシブル薄膜外科用接着剤、キトサンおよびインドシアニングリーンが記載されている。低出力の赤外線レーザーで簡単なアクティベーションプロセスによりコラーゲン組織にこの接着剤の接着性を示す。

ビデオ: A Chitosan Based, Laser Activated Thin Film Surgical Adhesive, 'SurgiLux': Preparation and Demonstration

Constructing a Collagen Hydrogel for the Delivery of Stem Cell-loaded Chitosan Microspheres

Multipotent stem cells have been shown to be extremely useful in the field of regenerative medicine1-3. However, in order to use these cells effectively for tissue regeneration, a number of variables must be taken into account. These variables include: the total volume and surface area of the implantation site, the mechanical properties of the tissue and the tissue microenvironment, which includes the amount of vascularization and the components of the extracellular matrix. Therefore, the materials being used to deliver these cells must be biocompatible with a defined chemical composition while maintaining a mechanical strength that mimics the host tissue. These materials must also be permeable to oxygen and nutrients to provide a favorable microenvironment for cells to attach and proliferate. Chitosan, a cationic polysaccharide with excellent biocompatibility, can be easily chemically modified and has a high affinity to bind with in vivo macromolecules4-5. Chitosan mimics the glycosaminoglycan portion of the extracellular matrix, enabling it to function as a substrate for cell adhesion, migration and proliferation. In this study we utilize chitosan in the form of microspheres to deliver adipose-derived stem cells (ASC) into a collagen based three-dimensional scaffold6. An ideal cell-to-microsphere ratio was determined with respect to incubation time and cell density to achieve maximum number of cells that could be loaded. Once ASC are seeded onto the chitosan microspheres (CSM), they are embedded in a collagen scaffold and can be maintained in culture for extended periods. In summary, this study provides a method to precisely deliver stem cells within a three dimensional biomaterial scaffold.

A major hurdle in current stem cell therapies is determining the most effective method to deliver these cells to host tissues. Here, we describe a chitosan-based delivery method that is efficient and simple in approach, while allowing adipose-derived stem cells to maintain their multipotency.

幹細胞にロードされたキトサンミクロスフェアの配信のためにコラーゲンハイドロゲルの構築

Multipotent stem cells have been shown to be extremely useful in the field of regenerative medicine1-3. However, in order to use these cells effectively ...

生物工学

Fabrication and Application of Rose Bengal-chitosan Films in Laser Tissue Repair

Photochemical tissue bonding (PTB) is a sutureless technique for tissue repair, which is achieved by applying a solution of rose bengal (RB) between two tissue edges1,2. These are then irradiated by a laser that is selectively absorbed by the RB. The resulting photochemical reactions supposedly crosslink the collagen fibers in the tissue with minimal heat production3. In this report, RB has been incorporated in thin chitosan films to fabricate a novel tissue adhesive that is laser-activated. Adhesive films, based on chitosan and containing ~0.1 wt% RB, are fabricated and bonded to calf intestine and rat tibial nerves by a solid state laser (&lambda;=532 nm, Fluence~110 J/cm2, spot size~0.5 cm). A single-column tensiometer, interfaced with a personal computer, is used to test the bonding strength. The RB-chitosan adhesive bonds firmly to the intestine with a strength of 15 &plusmn; 6 kPa, (n=30). The adhesion strength drops to 2 &plusmn; 2 kPa (n=30) when the laser is not applied to the adhesive. The anastomosis of tibial nerves can be also completed without the use of sutures. A novel chitosan adhesive has been fabricated that bonds photochemically to tissue and does not require sutures.

Sutures are usually needed to repair tissue during surgical procedures. However, their application can be problematic as they are invasive and may damage tissue. The fabrication and application methods of a novel tissue adhesive are here reported. This adhesive film is laser-activated and does not require the use of sutures.

レーザー組織修復にローズベンガル-キトサン膜の作製と応用

Photochemical tissue bonding (PTB) is a sutureless technique for tissue repair, which is achieved by applying a solution of rose bengal (RB) between two ...

Creating Adhesive and Soluble Gradients for Imaging Cell Migration with Fluorescence Microscopy

Cells can sense and migrate towards higher concentrations of adhesive cues such as the glycoproteins of the extracellular matrix and soluble cues such as growth factors. Here, we outline a method to create opposing gradients of adhesive and soluble cues in a microfluidic chamber, which is compatible with live cell imaging. A copolymer of poly-L-lysine and polyethylene glycol (PLL-PEG) is employed to passivate glass coverslips and prevent non-specific adsorption of biomolecules and cells. Next, microcontact printing or dip pen lithography are used to create tracks of streptavidin on the passivated surfaces to serve as anchoring points for the biotinylated peptide arginine-glycine-aspartic acid (RGD) as the adhesive cue. A microfluidic device is placed onto the modified surface and used to create the gradient of adhesive cues (100% RGD to 0% RGD) on the streptavidin tracks. Finally, the same microfluidic device is used to create a gradient of a chemoattractant such as fetal bovine serum (FBS), as the soluble cue in the opposite direction of the gradient of adhesive cues.

A method for the assembly of adhesive and soluble gradients in a microscopy chamber for live cell migration studies is described. The engineered environment combines antifouling surfaces and adhesive tracks with solution gradients and therefore allows one to determine the relative importance of guidance cues.

蛍光顕微鏡を用いたイメージング細胞遊走用接着剤及び可溶性グラデーションを作成する

Cells can sense and migrate towards higher concentrations of adhesive cues such as the glycoproteins of the extracellular matrix and soluble cues such as ...

Insertion of Flexible Neural Probes Using Rigid Stiffeners Attached with Biodissolvable Adhesive

Microelectrode arrays for neural interface devices that are made of biocompatible thin-film polymer are expected to have extended functional lifetime because the flexible material may minimize adverse tissue response caused by micromotion. However, their flexibility prevents them from being accurately inserted into neural tissue. This article demonstrates a method to temporarily attach a flexible microelectrode probe to a rigid stiffener using biodissolvable polyethylene glycol (PEG) to facilitate precise, surgical insertion of the probe. A unique stiffener design allows for uniform distribution of the PEG adhesive along the length of the probe. Flip-chip bonding, a common tool used in microelectronics packaging, enables accurate and repeatable alignment and attachment of the probe to the stiffener. The probe and stiffener are surgically implanted together, then the PEG is allowed to dissolve so that the stiffener can be extracted leaving the probe in place. Finally, an in vitro test method is used to evaluate stiffener extraction in an agarose gel model of brain tissue. This approach to implantation has proven particularly advantageous for longer flexible probes (&gt;3 mm). It also provides a feasible method to implant dual-sided flexible probes. To date, the technique has been used to obtain various in vivo recording data from the rat cortex.

Insertion of flexible neural microelectrode probes is enabled by attaching probes to rigid stiffeners with polyethylene glycol (PEG). A unique assembly process ensures uniform and repeatable attachment. After insertion into tissue, the PEG dissolves and the stiffener is extracted. An in vitro test method evaluates the technique in agarose gel.

生体溶解性接着剤で取り付けられている硬質補強材を用いた柔軟神経プローブの挿入

Microelectrode  arrays for neural interface devices that are made of biocompatible thin-film  polymer are expected to have extended functional lifetime ...

Development of Amelogenin-chitosan Hydrogel for In Vitro Enamel Regrowth with a Dense Interface

Biomimetic enamel reconstruction is a significant topic in material science and dentistry as a novel approach for the treatment of dental caries or erosion. Amelogenin has been proven to be a critical protein for controlling the organized growth of apatite crystals. In this paper, we present a detailed protocol for superficial enamel reconstruction by using a novel amelogenin-chitosan hydrogel. Compared to other conventional treatments, such as topical fluoride and mouthwash, this method not only has the potential to prevent the development of dental caries but also promotes significant and durable enamel restoration. The organized enamel-like microstructure regulated by amelogenin assemblies can significantly improve the mechanical properties of etched enamel, while the dense enamel-restoration interface formed by an in situ regrowth of apatite crystals can improve the effectiveness and durability of restorations. Furthermore, chitosan hydrogel is easy to use and can suppress bacterial infection, which is the major risk factor for the occurrence of dental caries. Therefore, this biocompatible and biodegradable amelogenin-chitosan hydrogel shows promise as a biomaterial for the prevention, restoration, and treatment of defective enamel.

Development of Amelogenin-chitosan Hydrogel for In Vitro Enamel Regrowth with a Dense Interface

In this article, we describe a protocol for fabricating an amelogenin-chitosan hydrogel for superficial enamel reconstruction. Organized in situ growth of apatite crystals in the hydrogel formed a dense enamel-restoration interface, which will improve the effectiveness and durability of restorations.

用アメロゲニン - キトサンハイドロゲルの開発<em&gt;体外</em高密度インターフェイス付き&gt;エナメル再成長

Biomimetic enamel reconstruction is a significant topic in material science and dentistry as a novel approach for the treatment of dental caries or ...

Custom-designed Laser-based Heating Apparatus for Triggered Release of Cisplatin from Thermosensitive Liposomes with Magnetic Resonance Image Guidance

Liposomes have been employed as drug delivery systems to target solid tumors through exploitation of the enhanced permeability and retention (EPR) effect resulting in significant reductions in systemic toxicity. Nonetheless, insufficient release of encapsulated drug from liposomes has limited their clinical efficacy. Temperature-sensitive liposomes have been engineered to provide site-specific release of drug in order to overcome the problem of limited tumor drug bioavailability. Our lab has designed and developed a heat-activated thermosensitive liposome formulation of cisplatin (CDDP), known as HTLC, to provide triggered release of CDDP at solid tumors. Heat-activated delivery in vivo was achieved in murine models using a custom-built laser-based heating apparatus that provides a conformal heating pattern at the tumor site as confirmed by MR thermometry (MRT). A fiber optic temperature monitoring device was used to measure the temperature in real-time during the entire heating period with online adjustment of heat delivery by alternating the laser power. Drug delivery was optimized under magnetic resonance (MR) image guidance by co-encapsulation of an MR contrast agent (i.e.,&#160;gadoteridol) along with CDDP into the thermosensitive liposomes as a means to validate the heating protocol and to assess tumor accumulation. The heating protocol consisted of a preheating period of 5 min prior to administration of HTLC and 20 min heating post-injection. This heating protocol resulted in effective release of the encapsulated agents with the highest MR signal change observed in the heated tumor in comparison to the unheated tumor and muscle. This study demonstrated the successful application of the laser-based heating apparatus for preclinical thermosensitive liposome development and the importance of MR-guided validation of the heating protocol for optimization of drug delivery.

AN MRI-compatible&#160;custom-designed laser-based heating apparatus has been developed to provide local heating of subcutaneous tumors in order to activate release of agents from thermosensitive liposomes specifically at the tumor region.

磁気共鳴画像誘導による感熱リポソームからのシスプラチンのトリガリリースのためのカスタム設計されたレーザーベースの加熱装置

Liposomes have been employed as drug delivery systems to target solid tumors through exploitation of the enhanced permeability and retention (EPR) effect ...

Automated Lipid Bilayer Membrane Formation Using a Polydimethylsiloxane Thin Film

An artificial lipid bilayer, or black lipid membrane (BLM), is a powerful tool for studying ion channels and protein interactions, as well as for biosensor applications. However, conventional BLM formation techniques have several drawbacks and they often require specific expertise and laborious processes. In particular, conventional BLMs suffer from low formation success rates and inconsistent membrane formation time. Here, we demonstrate a storable and transportable BLM formation system with controlled thinning-out time and enhanced BLM formation rate by replacing conventionally used films (polytetrafluoroethylene, polyoxymethylene, polystyrene) to polydimethylsiloxane (PDMS). In this experiment, a porous-structured polymer such as PDMS thin film is used. In addition, as opposed to conventionally used solvents with low viscosity, the use of squalene permitted a controlled thinning-out time via slow solvent absorption by PDMS, prolonging membrane lifetime. In addition, by using a mixture of squalene and hexadecane, the freezing point of the lipid solution was increased (~16 &#176;C), in addition, membrane precursors were produced that can be indefinitely stored and readily transported. These membrane precursors have reduced BLM formation time of &#60; 1 hr and achieved a BLM formation rate of ~80%. Moreover, ion channel experiments with gramicidin A demonstrated the feasibility of the membrane system.

We demonstrate a storable, transportable lipid bilayer formation system. A lipid bilayer membrane can be formed within 1 hr with over 80% success rate when a frozen membrane precursor is brought to ambient temperature. This system will reduce laborious processes and expertise associated with ion channels.

ポリジメチルシロキサン薄膜を用いた自動化された脂質二重膜の形成

An artificial lipid bilayer, or black lipid membrane (BLM), is a powerful tool for studying ion channels and protein interactions, as well as for ...

Image-guided, Laser-based Fabrication of Vascular-derived Microfluidic Networks

This detailed protocol outlines the implementation of image-guided, laser-based hydrogel degradation for the fabrication of vascular-derived microfluidic networks embedded in PEGDA hydrogels. Here, we describe the creation of virtual masks that allow for image-guided laser control; the photopolymerization of a micromolded PEGDA hydrogel, suitable for microfluidic network fabrication and pressure head-driven flow; the setup and use of a commercially available laser scanning confocal microscope paired with a femtosecond pulsed Ti:S laser to induce hydrogel degradation; and the imaging of fabricated microfluidic networks using fluorescent species and confocal microscopy. Much of the protocol is focused on the proper setup and implementation of the microscope software and microscope macro, as these are crucial steps in using a commercial microscope for microfluidic fabrication purposes that contain a number of intricacies. The image-guided component of this technique allows for the implementation of 3D image stacks or user-generated 3D models, thereby allowing for creative microfluidic design and for the fabrication of complex microfluidic systems of virtually any configuration. With an expected impact in tissue engineering, the methods outlined in this protocol could aid in the fabrication of advanced biomimetic microtissue constructs for organ- and human-on-a-chip devices. By mimicking the complex architecture, tortuosity, size, and density of in vivo vasculature, essential biological transport processes can be replicated in these constructs, leading to more accurate in vitro modeling of drug pharmacokinetics and disease.

This protocol outlines the implementation of image-guided, laser-based hydrogel degradation to fabricate vascular-derived, biomimetic microfluidic networks embedded in poly(ethylene glycol) diacrylate (PEGDA) hydrogels. These biomimetic microfluidic systems may be useful for tissue engineering applications, generation of in vitro disease models, and fabrication of advanced "on-a-chip" devices.

血管由来のマイクロ流体ネットワークの画像誘導、レーザーベースの試作

This detailed protocol outlines the implementation of image-guided, laser-based hydrogel degradation for the fabrication of vascular-derived microfluidic ...

Dry Film Photoresist-based Electrochemical Microfluidic Biosensor Platform: Device Fabrication, On-chip Assay Preparation, and System Operation

In recent years, biomarker diagnostics became an indispensable tool for the diagnosis of human disease, especially for the point-of-care diagnostics. An easy-to-use and low-cost sensor platform is highly desired to measure various types of analytes (e.g., biomarkers, hormones, and drugs) quantitatively and specifically. For this reason, dry film photoresist technology - enabling cheap, facile, and high-throughput fabrication - was used to manufacture the microfluidic biosensor presented here. Depending on the bioassay used afterwards, the versatile platform is capable of detecting various types of biomolecules. For the fabrication of the device, platinum electrodes are structured on a flexible polyimide (PI) foil in the only clean-room process step. The PI foil serves as a substrate for the electrodes, which are insulated with an epoxy-based photoresist. The microfluidic channel is subsequently generated by the development and lamination of dry film photoresist (DFR) foils onto the PI wafer. By using a hydrophobic stopping barrier in the channel, the channel is separated into two specific areas: an immobilization section for the enzyme-linked assay and an electrochemical measurement cell for the amperometric signal readout.
The on-chip bioassay immobilization is performed by the adsorption of the biomolecules to the channel surface. The glucose oxidase enzyme is used as a transducer for electrochemical signal generation. In the presence of the substrate, glucose, hydrogen peroxide is produced, which is detected at the platinum working electrode. The stop-flow technique is applied to obtain signal amplification along with rapid detection. Different biomolecules can quantitatively be measured by means of the introduced microfluidic system, giving an indication of different types of diseases, or, in regard to therapeutic drug monitoring, facilitating a personalized therapy.

A microfluidic biosensor platform was designed and fabricated using low-cost dry film photoresist technology for the rapid and sensitive quantification of various analytes. This single-use system allows for the electrochemical readout of on-chip-immobilized enzyme-linked assays by means of the stop-flow technique.

ドライ フィルムのレジストを用いた電気化学マイクロ流体バイオ プラットフォーム: デバイス作製、チップの試金の準備、およびシステム操作

In recent years, biomarker diagnostics became an indispensable tool for the diagnosis of human disease, especially for the point-of-care diagnostics. An ...

Rat Model of Adhesive Capsulitis of the Shoulder

This proposal aims to create an in vivo rat model of adhesive capsulitis for researching potential treatment options for this condition and other etiologies of comparable arthrofibrosis. The model includes extra-articular fixation of the shoulder in rats via scapular to humeral suturing, resulting in a secondary contracture without invading the intra-articular space and resulting in decreased rotational ROM and increased joint stiffness.
We used 10 Sprague-Dawley rats for the purpose of this study. Baseline ROM measurements were taken before glenohumeral immobilization. The rats were subjected to 8 weeks of immobilization before the fixation sutures were removed and changes in ROM and joint stiffness were evaluated. To evaluate whether immobilization resulted in a significant reduction in ROM, changes in kinematics were calculated. ROM was measured at each time point in the follow-up period and was compared to the baseline internal and external ROM measurements. In order to evaluate the stiffness, joint kinetics were calculated by determining the differences in torque (text and tint ) needed to reach the initial external rotation of 60&#176; and initial internal rotation of 80&#176;.
After the removal of the extra-articular suture fixation on follow-up day 0, we found a 63% decrease in total ROM compared to baseline. We observed continuous improvement until week 5 of follow-up, with the progress slowing down around a 19% restriction. On week 8 of follow-up, there was still an 18% restriction of ROM. Additionally, on follow-up day 0, we found the torque increased by 13.3 Nmm when compared to baseline. On week 8, the total torque was measured to be 1.4 &#177; 0.2 Nmm higher than initial measurements. This work introduces a rat model of shoulder adhesive capsulitis with lasting reduced ROM and increased stiffness.

This protocol presents an in vivo rat model of adhesive capsulitis. The model includes an internal fixation of the glenohumeral joint with extra-articular suture fixation for an extended time, resulting in a decreased rotational range of motion (ROM) and increased joint stiffness.