この作品は、化学科からと研究局（RCAP 13から8032）からの内部サポートを含め、科学と工学のウェスタンケンタッキー大学のオグデン大学によってサポートされています。 WKU顕微鏡施設でドクター・ジョンAndersland（SEM像）と、燃焼科学と工学（BET分析）のためWKU研究所の准教授ヤン曹操の支援は、この作業を行うの中心となっています。

エマルジョンの調製<ol><li>エマルジョンの内容<ol><li>質量は、塩の適切な量は、0.03-M溶液10mlを作製しました。プラチナ、亜鉛（II）クロリド（のZnCl 2）尺度0.032 g及び塩化ナトリウム（NaCl）で測定値0.018 gで（IV）、塩化尺度0.101 gでした。 </li><li>個々の試験管において、脱イオン水10ml中に各塩を溶解します。後で使用するために脇に置きます。 </li><li>この手順全体の内容のために20ミリリットル、密封可能なガラスバイアルを使用します。ガラスバイアルに風袋引き。 </li><li>ゆっくりと攪拌棒を越えてゼロ化された規模で休んでガラスバイアルにそれを注ぐことによって、ビニル末端ポリジメチルシロキサンを計量。 （1.080ミリリットルに相当）1.02グラムを計量。 注：このポリ​​マーの高粘度は、ピペッティングは非現実的になります。 </li><li>ピペットバイアルにn-ヘプタンの1.02ミリリットル。バイアルに非イオン性界面活性剤（モノオレイン酸ソルビタン）の2滴を追加します。ピペット塩溶液の0.3ミリリットルバイアルにDI水の0.45ミリリットル。 </li><li>しっかりと蓋をネジ止めすることにより、ガラスバイアルを密封。超音波処理を開始する前に、エマルジョンを開始するために60秒間激しく振ります。 </li></ol></li><li>水浴超音波処理装置の構成<ol><li>最小充填ラインまで水で超音波処理器を埋めます。 400ミリリットルのビーカーに水道水250ミリリットルを追加します。水位がちょうど縁にあるように氷で400ミリリットルのビーカーを埋めます。 </li><li>水浴ソニケーター内でこのビーカーを置きます。必要に応じて調整し、超音波処理器に充填ラインを確認してください。リングは水浴超音波処理のすぐ横に立って置きます。 </li><li>アームが引き出されているように、2つのリングは、クランプをスタンドにそれらを配置し使用して、リングに垂直に立って、それが氷の水で満たされたビーカーに下向きとなるように別のものを水槽に向けて延長されます。リングに別のクランプを取り付け、温度が超音波処理を通してモニターすることができるように400ミリリットルのビーカーにダウン温度計を立ちます。 </li></ol></li><li> Emulsification手順<ol><li>それは完全にビーカーにダウン突出クランプにそれを固定することによって、400 mlのビーカーに沈められるようにエマルジョンを含むバイアルを置きます。 </li><li> PDMSの混合物を含有するガラスバイアルは摩擦による熱を除去するために、ビーカーの側面に触れていないことを確認してください。 </li><li>超音波処理装置の電源をオンにし、7分間の超音波処理時間を設定します。エマルジョンは敏感非常に熱であるため、ビーカー内の温度は、超音波処理を通じて、0〜5℃の間であることを確認してください。ビーカー内の温度が望ましいたら、超音波処理を開始します。 </li><li>超音波処理の7分後、バイアルを取り外し、ゆっくりとエマルジョン中に形成する可能性の塊を除去するために、バイアルの上部を保持し、1分間/スワールを振ります。 </li><li>ビーカーの内容物を廃棄してください。 250mlの水を補充し、ビーカーの上部CM 1内に充填するために氷を追加します。 </li><li>バッククランプでバイアルを置きます。 RESUMに氷水下でそれを沈めます7分の電子の超音波処理。 </li><li>繰り返しは、8の合計1.3.6に7分間超音波処理期間を1.3.3ステップ、または超音波処理は、均質であることが表示され、何の塊が存在しなくなるまで。室温で保管してください。 注：乳化は数日間安定であるべきであり、それが均質に表示されるまで、7分間隔で、上記のように超音波処理することによって回収することができます。室温で保管してください。 </li></ol></li></ol> 2.架橋<ol><li>トリエトキシシラン/界面活性剤溶液を添加するためのセットアップ<ol><li>試験管に5.4ミリリットルトリエトキシシランをピペット。後で使用するためにボンネットの下に試験管ラックに配置します。 </li><li>氷水で400ミリリットルのビーカーを記入し、ボンネットの下に置きます。次にリングを取り付けクランプでスタンド400ミリリットルのビーカーの場所に、ビーカーの開口部の真上に拡張しました。これは、トリエトキシシランの添加のための氷浴になります。 </li><li>リングスタンドの反対側にホットプレートを置きます。約700ミリリットルで800ミリリットルのビーカーを埋めます水道水。ホットプレートの上に置きます。 </li><li>ホットプレートの電源をオンにし、800ミリリットルのビーカーの内側75〜85℃の温度を維持します。 800ミリリットルのビーカー内の水の温度を監視することができるようにリングスタンドに温度計をクランプを取り付けます。 </li><li>水の375ミリリットル（4.62ミリモル）にドデシル硫酸ナトリウムを0.5gを溶解させて界面活性剤溶液を生成します。きれいな、空の試験管に界面活性剤溶液の約10ミリリットルを追加します。 </li><li>界面活性剤の試験管にボンネットの下にリングスタンドに別のクランプを取り付けすると、その液面が800ミリリットルビーカー内の水の表面の下になるように固定されています。熱平衡のために10分を許可します。 </li><li>濾紙を湿らせ、小さな漏斗の上部に配置します。 250mlの三角フラスコ内の漏斗の茎を置き、ボンネットの下にフラスコを置きます。 </li></ol></li><li>トリエトキシシランを添加します<ol><li>氷水のくちばしの上にクランプでエマルジョンバイアルを置きますフード内側えー。バイアル内容物は、水の表面の下になるようにクランプでPDMS混合物を置きます。トリエトキシシランの添加は発熱反応を起こすので、エマルジョンは、その構造を維持するために、冷保たなければなりません。 </li><li>気体の蓄積を回避するために、ガラスバイアルから蓋を外します。 </li><li>ゆっくりと約10秒（約0.5ミリリットル/秒）の期間にわたって連続的な流れでガラスバイアルにトリエトキシシランを含有する試験管を注ぎます。 注意：トリエトキシシランの添加は発熱反応と苛性塩化水素（HCl）ガスの放出を開始します。バイアルは、非常に高温になり、有毒ガスが混合物から進化していきます。トリエトキシシランを添加しながら、内容を攪拌しないでください。 </li><li>熱保護手袋を着用したまま完全にトリエトキシシランを添加した後、ゆっくりとガラス撹拌棒で中身をかき混ぜます。 2分間またはバイアルから進化したガスが停止するまで待ちます。 </li><li> Foll架橋のため、試料中の目に見える相分離は存在しません。塊が存在している場合は、バイアルを密封し、蓋によってバイアルを保持しながら20秒間厳密に振ります。 </li></ol></li><li>ビーズ生産<ol><li>ガラス瓶から架橋されたエマルジョンを描くようにきれいな、ガラスパスツールピペットを使用してください。液滴間でできるだけ時間をかけ試験管に架橋されたエマルションの滴下界面活性剤溶液に（75および85℃の間に維持すべきである）を加えます。 </li><li> 1分30秒のエマルジョンを添加した後、界面活性剤溶液をゆっくりと固体が試験管の内部に形成され始めるようにガスを発生し始めます。 </li><li>熱保護手袋を装着したまま、クランプのうち、試験管を取り、ボンネットの下に濾過装置にその内容全体を注ぎます。 5分間フィルター。フィルターからろ紙を取り除きます。 </li><li> Hの下でO / Nの乾燥のために時計のガラス、別のビーズ上に濾過した固体を転送OOD。ビーズの洗浄は、無期限に延期することができます。ストアは、必要になるまで密封したガラスバイアル中で、室温でビーズを乾燥させ、きれいな、使用直前に。 </li></ol></li><li>ビーズクリーニング<ol><li>ボンネットの下に別の濾過装置を作成し、ろ紙の上に漏斗内部乾燥ビーズを配置します。 </li><li>すべてのビーズがすすぎされることを保証するために、わずかにそれらを動き回る、優しくビーズを洗浄するために脱イオン水で満たされたプラスチック製の洗浄ボトルを使用してください。 </li><li>ビーズはフードの下時計皿の上にそれらを配置することによって、1時間乾燥させます。水ですすぐために同じ方法を用いてビーズを洗浄するためにヘキサンを充填した洗浄ボトルを使用してください。 </li><li>時計皿の上にビーズを配置します。乾燥するためにボンネットの下に時計のガラスビーズを置きます。 </li><li>ビーズが完全に乾燥した後、将来の使用のために室温で小さな密閉可能なガラスバイアルとストアに配置します。 </li></ol></li><li> SEM分析とSEMの設定のためのビーズを取り付け<ol><li> DOのストリップを配置しますビーズがマウントされる上に、スタブの上にUBLE両面カーボン導電性テープ。はさみを使用して、エッジの上に何のテープハングを保証しないようにスタブを中心にトリミングします。 </li><li>平らな表面上のスタブの下に濾紙を置きます。接着剤下面が露出するようにテープから最上層を削除します。 </li><li>ゆっくりスタブの上にビーズを注ぎます。いくつかのビーズは、テープに固執するが、ほとんどは跳ね返るとろ紙上に着陸する予定。彼らはろ紙上にとどまった場合、バイアルにこれらのバックを注ぎます。必要に応じて汚染される（2.4.5を2.4.2による）任意のビーズを洗浄、繰り返します。 </li><li>ビーズは、スタブ上で固定されていることを保証するために、電球の注射器を使用し、軽くスタブ表面に非常に密接に吹きます。わずか数がテープに付着した場合は、スタブ上でより多くのビーズを注ぎます。すべてのビーズをSEM室にスタブを配置し、それを排出する前に、安全であることを確認してください。 </li><li>サンプルが正常にマウントされた後、彼らは今のSEM肛門を受ける準備ができていますysis 15。ビーズの表面の特徴の解像度を最適化するために、15 keVの時にLOW VACモードで画像を収集します。 </li></ol></li></ol>

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The authors have nothing to disclose.

図1の他のSEM画像を図1（a）の比較によって分かるように、このプロトコル（および電解質濃度及びアイデンティティを調節することによって）を用いて製造ビーズは、低イオン強度のエマルジ ​​ョンで製造されたものとは根本的に異なっている。使用する我々の最初の報告さらに水-脂肪族インターフェース 14で重合架橋を触媒することを意図してのPtCl <s...

Polydimethylsiloxane (PDMS) is one of the most widely used silicone compounds. Its biocompatibility has led to widespread use in implant and other biomedical engineering structures1,2. It is trivially cross-linked into elastic structures using an organosilyl compound (such as triethoxysilane), a simple and reliable procedure which has made it useful for cast polymer applications where some flexibility is required3. Once cross-linked, PDMS is largely inert, particularly in biological conditions, and is therefore useful for a variety of food and medical applications4,5. Ease of casting, chemical inertness, and hydrophobicity have made it a natural choice for microfluidic devices6,7. Its affinity for non-halogenated, non-polar organic compounds has made it a popular stationary phase in separations chemistry8-10. 
Recently, microbubble fabrications have been used to generate porous beads for use as catalyst structural substrates or in chemical separations11,12. In both applications, ideal materials will have a maximized surface-area-to-volume (SAV) ratio for best efficiency. In a microbubble fabrication process, microstructuring of materials is typically accomplished by isolating the polymer in aliphatic &#8220;microbubbles&#8221; by emulsification in an aqueous continuous phase. The initial report of microporous PDMS beads produced them by mechanical emulsification of two phases (aliphatic and aqueous)13. The stock PDMS liquid (and its cross-linking agent) is dissolved into the aliphatic phase, which is structured into microscopic beads by being forced to cavitate within the (continuous) aqueous phase. The emulsification is stabilized by the addition of a non-ionic surfactant. When the emulsion is added dropwise to a heated bath, solid beads form by agglomeration of the microbubbles into clusters of tiny spheres of cross-linked PDMS. Our goal in this protocol is to modify this procedure to develop beads with an inverted porosity to improve the SAV ratio of the material.
As reported previously, control of the beads can be directed to some extent by the aliphatic:aqueous ratios in the emulsion. However, we have reported recently that addition of platinum(IV) chloride (PtCl4) inverts the porosity: materials are formed in which the PDMS is riddled with concave pores14. This indicates that the aqueous layer cavitates inside the aliphatic one, despite having similar aliphatic:aqueous ratios to those published in the original work13. The primary advantage of our method is that this concave porosity should naturally result in an increased SAV ratio, and thus, improved efficiency for analytical chemistry applications. While we are continuing to explore the specific effects of the addition of the platinum compound, we show here that the same effect can be accomplished using any aqueously soluble ionic compound, though perhaps to a reduced extent. Because our techniques also differ in some key aspects from what has been previously reported, we present our protocols here as a video to encourage others to extend our methods. Most notably, we use a common bath sonicator of the type used to clean glassware or other equipment, rather than the (considerably more expensive) probe sonicator often used in microbubble fabrication. This adjusted approach to the microbubble fabrication procedure could potentially be extended for the production of large quantities of bulk materials as well, creating porous sheets or slabs which could have applications for biomedical devices, aerospace and automotive industry, or substrates for chemical catalysis. Users seeking to generate high-SAV-ratio, microstructured materials using other similar polymers for such analyses may find that our protocols can be extended to any polymer for which the microbubble emulsion technique can be applied.

<table border="0">
	<tbody>
		<tr>
			<td>Poly(dimethylsiloxane), vinyl terminated</td>
			<td>Sigma-Aldrich</td>
			<td>68083-19-2</td>
			<td></td>
		</tr>
		<tr>
			<td>n-Heptane</td>
			<td>Sigma-Aldrich</td>
			<td>142-82-5</td>
			<td>Flammable</td>
		</tr>
		<tr>
			<td>Triethoxysilane</td>
			<td>Sigma-Aldrich</td>
			<td>998-30-1</td>
			<td>Flammable, Accutely Toxic</td>
		</tr>
		<tr>
			<td>Sorbitan Monoleate (Span-80)</td>
			<td>Fluker</td>
			<td>1338-43-8</td>
			<td></td>
		</tr>
		<tr>
			<td>Platinum (IV) Chloride</td>
			<td>Sigma-Aldrich</td>
			<td>13454-96-1</td>
			<td>Accutely Toxic</td>
		</tr>
		<tr>
			<td>Zinc (II) Chloride</td>
			<td>Sigma-Aldrich</td>
			<td>7646-85-7</td>
			<td></td>
		</tr>
		<tr>
			<td>Sodium Chloride</td>
			<td>Sigma-Aldrich</td>
			<td>7647-14-5</td>
			<td></td>
		</tr>
		<tr>
			<td>2.8L Water Bath Sonicator</td>
			<td>VWR</td>
			<td>97043-964</td>
			<td></td>
		</tr>
	</tbody>
</table>

microbubble fabrication of concave-porosity pdms beads

Microbubble fabrication (by use of a fine emulsion) provides a means of increasing the surface-area-to-volume (SAV) ratio of polymer materials, which is particularly useful for separations applications. Porous polydimethylsiloxane (PDMS) beads can be produced by heat-curing such an emulsion, allowing the interface between the aqueous and aliphatic phases to mold the morphology of the polymer. In the procedures described here, both polymer and crosslinker (triethoxysilane) are sonicated together in a cold-bath sonicator. Following a period of cross-linking, emulsions are added dropwise to a hot surfactant solution, allowing the aqueous phase of the emulsion to separate, and forming porous polymer beads. We demonstrate that this method can be tuned, and the SAV ratio optimized, by adjusting the electrolyte content of the aqueous phase in the emulsion. Beads produced in this way are imaged with scanning electron microscopy, and representative SAV ratios are determined using Brunauer&#8211;Emmett&#8211;Teller (BET) analysis. Considerable variability with the electrolyte identity is observed, but the general trend is consistent: there is a maximum in SAV obtained at a specific concentration, after which porosity decreases markedly.

異なる電解条件エマルジ ​​ョンから生じるビーズの代表的なSEM像を図1に示す 。 図1Aは DuFaudしたもの、 ら 13に類似したビーズを示し、任意の電解質を添加せずに、我々の手順を用いて製造。ビーズは、各金属イオンのための別の形態で得られ、 図1B-Dに示します。示された全ての画像については、0.03-Mの電解質溶液の300μl?...

Watch this Scientific Journal Video about Microbubble Fabrication of Concave-porosity PDMS Beads at JoVE.com

Microbubble Fabrication of Concave-porosity PDMS Beads

Procedures used to generate microstructured concave-porosity polydimethylsiloxane beads are presented. Effects of electrolyte concentration and identity within the aqueous phase are particularly emphasized.

凹面気孔率PDMSビーズのマイクロバブル作製

Microbubble fabrication (by use of a fine emulsion) provides a means of increasing the surface-area-to-volume (SAV) ratio of polymer materials, which is ...

microbubble-fabrication-of-concave-porosity-pdms-beads

Research

JoVE Journal

Chemistry

8.2K ビュー.  Western Kentucky University. Procedures used to generate microstructured concave-porosity polydimethylsiloxane beads are presented. Effects of electrolyte concentration and identity within the aqueous phase are particularly emphasized. 

ビデオ: Microbubble Fabrication of Concave-porosity PDMS Beads

Synthesis of Indoxyl-glycosides for Detection of Glycosidase Activities

Indoxyl glycosides proved to be valuable and versatile tools for monitoring glycosidase activities. Indoxyls are released by enzymatic hydrolysis and are rapidly oxidized, for example by atmospheric oxygen, to indigo type dyes. This reaction enables fast and easy screening in vivo without isolation or purification of enzymes, as well as rapid tests on agar plates or in solution (e.g., blue-white screening, micro-wells) and is used in biochemistry, histochemistry, bacteriology and molecular biology. Unfortunately the synthesis of such substrates proved to be difficult, due to various side reactions and the low reactivity of the indoxyl hydroxyl function. Especially for glucose type structures low yields were observed. Our novel approach employs indoxylic acid ester as key intermediates. Indoxylic acid esters with varied substitution patterns were prepared on scalable pathways. Phase transfer glycosylations with those acceptors and peracetylated glycosyl halides can be performed under common conditions in high yields. Ester cleavage and subsequent mild silver mediated glycosylation yields the peracetylated indoxyl glycosides in high yields. Finally deprotection is performed according to Zempl&#233;n.

Indoxyl glycosides are well-established and widely used tools for enzyme screening and enzyme activity monitoring. Especially for glucose type structures previous syntheses proved to be challenging and low yielding. Our novel approach employs indoxylic acid esters as precious intermediates to yield a considerable number of indoxyl glycosides in good yields.

グリコシダーゼ活性の検出のためのインドキシル配糖体の合成

Indoxyl glycosides proved to be valuable and versatile tools for monitoring glycosidase activities. Indoxyls are released by enzymatic hydrolysis and are ...

化学

Fabrication of Large-area Free-standing Ultrathin Polymer Films

This procedure describes a method for the fabrication of large-area and ultrathin free-standing polymer films. Typically, ultrathin films are prepared using either sacrificial layers, which may damage the film or affect its mechanical properties, or they are made on freshly cleaved mica, a substrate that is difficult to scale. Further, the size of ultrathin film is typically limited to a few square millimeters. In this method, we modify a surface with a polyelectrolyte that alters the strength of adhesion between polymer and deposition substrate. The polyelectrolyte can be shown to remain on the wafer using spectroscopy, and a treated wafer can be used to produce multiple films, indicating that at best minimal amounts of the polyelectrolyte are added to the film. The process has thus far been shown to be limited in scalability only by the size of the coating equipment, and is expected to be readily scalable to industrial processes. In this study, the protocol for making the solutions, preparing the deposition surface, and producing the films is described.

We describe a method for the fabrication of large-area (up to 13 cm diameter) and ultrathin (as thin as 8 nm) polymer films. Instead of using a sacrificial interlayer to delaminate the film from its substrate, we use a self-limiting surface treatment suitable for arbitrarily large areas.

大面積自立超薄ポリマーフィルムの作製

This procedure describes a method for the fabrication of large-area and ultrathin free-standing polymer films.  Typically, ultrathin films are prepared ...

Flow-pattern Guided Fabrication of High-density Barcode Antibody Microarray

Antibody microarray as a well-developed technology is currently challenged by a few other established or emerging high-throughput technologies. In this report, we renovate the antibody microarray technology by using a novel approach for manufacturing and by introducing new features. The fabrication of our high-density antibody microarray is accomplished through perpendicularly oriented flow-patterning of single stranded DNAs and subsequent conversion mediated by DNA-antibody conjugates. This protocol outlines the critical steps in flow-patterning DNA, producing and purifying DNA-antibody conjugates, and assessing the quality of the fabricated microarray. The uniformity and sensitivity are comparable with conventional microarrays, while our microarray fabrication does not require the assistance of an array printer and can be performed in most research laboratories. The other major advantage is that the size of our microarray units is 10 times smaller than that of printed arrays, offering the unique capability of analyzing functional proteins from single cells when interfacing with generic microchip designs. This barcode technology can be widely employed in biomarker detection, cell signaling studies, tissue engineering, and a variety of clinical applications.

This protocol outlines the fabrication of a large-scale, multiplexed two-dimensional DNA or antibody array, with potential applications in cell signaling studies and biomarker detection.

高密度バーコード抗体マイクロアレイのフローパターンガイド作製

Antibody microarray as a well-developed technology is currently challenged by a few other established or emerging high-throughput technologies. In this ...

Immobilization of Multi-biocatalysts in Alginate Beads for Cofactor Regeneration and Improved Reusability

We have recently developed a simple, reusable and coupled whole-cell biocatalytic system with the capability of cofactor regeneration and biocatalyst immobilization for improved production yield and sustained synthesis. Described herewith is the experimental procedure for the development of such a system consisting of two E. coli strains that express functionally complementary enzymes. Together, these two enzymes can function co-operatively to mediate the regeneration of expensive cofactors for improving the product yield of the bioreaction. In addition, the method of synthesizing an immobilized form of the coupled biocatalytic system by encapsulation of whole cells in calcium alginate beads is reported. As an example, we present the improved biosynthesis of L-xylulose from L-arabinitol by coupling E. coli cells expressing the enzymes L-arabinitol dehydrogenase or NADH oxidase. Under optimal conditions and using an initial concentration of 150 mM L-arabinitol, the maximal L-xylulose yield reached 96%, which is higher than those reported in the literature. The immobilized form of the coupled whole-cell biocatalysts demonstrated good operational stability, maintaining 65% of the yield obtained in the first cycle after 7 cycles of successive re-use, while the free cell system almost completely lost the catalytic activity. Therefore, the methods reported here provides two strategies that could help improve the industrial production of L-xylulose, as well as other value-added compounds requiring the use of cofactors in general.

Presented is the protocol for co-immobilizing whole-cell biocatalysts for cofactor regeneration and improved reusability, using the production of L-xylulose as an example. The cofactor regeneration is achieved by coupling two Escherichia coli strains expressing functionally complementary enzymes; the whole-cell biocatalyst immobilization is achieved by cell encapsulation in calcium alginate beads.

補因子再生と改善された再利用のためのアルギン酸ビーズでマルチ生体触媒の固定化

We have recently developed a simple, reusable and coupled whole-cell biocatalytic system with the capability of cofactor regeneration and biocatalyst ...

Influence of Hybrid Perovskite Fabrication Methods on Film Formation, Electronic Structure, and Solar Cell Performance

Hybrid organic/inorganic halide perovskites have lately been a topic of great interest in the field of solar cell applications, with the potential to achieve device efficiencies exceeding other thin film device technologies. Yet, large variations in device efficiency and basic physical properties are reported. This is due to unintentional variations during film processing, which have not been sufficiently investigated so far. We therefore conducted an extensive study of the morphology and electronic structure of a large number of CH3NH3PbI3 perovskite where we show how the preparation method as well as the mixing ratio of educts methylammonium iodide and lead(II) iodide impact properties like film formation, crystal structure, density of states, energy levels, and ultimately the solar cell performance.

We present an extensive study on the effects of different fabrication methods for organic/inorganic perovskite thin films by comparing crystal structures, density of states, energy levels, and ultimately the solar cell performance.

製膜上のハイブリッドペロブスカイト製造方法、電子構造、および太陽電池の性能に及ぼす影響

Hybrid organic/inorganic halide perovskites have lately been a topic of great interest in the field of solar cell applications, with the potential to ...

Fabrication and Testing of Photonic Thermometers

In recent years, a push for developing novel silicon photonic devices for telecommunications has generated a vast knowledge base that is now being leveraged for developing sophisticated photonic sensors. Silicon photonic sensors seek to exploit the strong confinement of light in nano-waveguides to transduce changes in physical state to changes in resonance frequency. In the case of thermometry, the thermo-optic coefficient, i.e., changes in refractive index due to temperature, causes the resonant frequency of the photonic device such as a Bragg grating to drift with temperature. We are developing a suite of photonic devices that leverage recent advances in telecom compatible light sources to fabricate cost-effective photonic temperature sensors, which can be deployed in a wide variety of settings ranging from controlled laboratory conditions, to the noisy environment of a factory floor or a residence. In this manuscript, we detail our protocol for the fabrication and testing of photonic thermometers.

We describe the process of fabrication and testing of photonic thermometers.

光温度計の作製と試験

In recent years, a push for developing novel silicon photonic devices for telecommunications has generated a vast knowledge base that is now being ...

Fabrication of Spherical and Worm-shaped Micellar Nanocrystals by Combining Electrospray, Self-assembly, and Solvent-based Structure Control

Micellar nanocrystals (micelles with encapsulated nanocrystals) have become an emerging major class of nanobiomaterials. We describe a method of fabricating micellar nanocrystals based on combining top-down electrospray, bottom-up self-assembly, and solvent-based structure control. This method involves first using electrospray to generate uniform ultrafine liquid droplets, each of which functions as a micro-reactor in which self-assembly reaction occurs forming micellar nanocrystals, with the structures (micelle shape and nanocrystal encapsulation) controlled by the organic solvent used. This method is largely continuous and produces high quality micellar nanocrystal products with an inexpensive structure control approach. By using a water-miscible organic solvent tetrahydrofuran (THF), worm-shaped micellar nanocrystals can be produced due to solvent-induced/facilitated micelle fusion. Compared with the common spherical micellar nanocrystals, worm-shaped micellar nanocrystals can offer minimized non-specific cellular uptake, thus enhancing biological targeting. By co-encapsulating multiple nanocrystals into each micelle, multifunctional or synergistic effects can be achieved. Current limitations of this fabrication method, which will be part of the future work, primarily include imperfect encapsulation in the micellar nanocrystal product and the incompletely continuous nature of the process.

The present work describes a method to fabricate micellar nanocrystals, an emerging major class of nanobiomaterials. This method combines top-down electrospray, bottom-up self-assembly, and solvent-based structure control. The fabrication method is largely continuous, can produce high quality products, and possesses an inexpensive means of structure control.

組み立て式、エレクトロ スプレーを組み合わせることによって球形とワーム状ミセル ナノ結晶と溶剤ベースの構造制御の作製

Micellar nanocrystals (micelles with encapsulated nanocrystals) have become an emerging major class of nanobiomaterials. We describe a method of ...

Fabrication and Testing of Catalytic Aerogels Prepared Via Rapid Supercritical Extraction

Protocols for preparing and testing catalytic aerogels by incorporating metal species into silica and alumina aerogel platforms are presented. Three preparation methods are described: (a) the incorporation of metal salts into silica or alumina wet gels using an impregnation method; (b) the incorporation of metal salts into alumina wet gels using a co-precursor method; and (c) the addition of metal nanoparticles directly into a silica aerogel precursor mixture. The methods utilize a hydraulic hot press, which allows for rapid (&#60;6 h) supercritical extraction and results in aerogels of low density (0.10 g/mL) and high surface area (200-800 m2/g). While the work presented here focuses on the use of copper salts and copper nanoparticles, the approach can be implemented using other metal salts and nanoparticles. A protocol for testing the three-way catalytic ability of these aerogels for automotive pollution mitigation is also presented. This technique uses custom-built equipment, the Union Catalytic Testbed (UCAT), in which a simulated exhaust mixture is passed over an aerogel sample at a controlled temperature and flow rate. The system is capable of measuring the ability of the catalytic aerogels, under both oxidizing and reducing conditions, to convert CO, NO and unburned hydrocarbons (HCs) to less harmful species (CO2, H2O and N2). Example catalytic results are presented for the aerogels described.

Here we present protocols for preparing and testing catalytic aerogels by incorporating metal species into silica and alumina aerogel platforms. Methods for preparing materials using copper salts and copper-containing nanoparticles are featured. Catalytic testing protocols demonstrate the effectiveness of these aerogels for three-way catalysis applications.

急速な超臨界抽出法によって作製した触媒のエアロゲルの作製と試験

Protocols for preparing and testing catalytic aerogels by incorporating metal species into silica and alumina aerogel platforms are presented. Three ...

Preparation of Poly(pentafluorophenyl acrylate) Functionalized SiO2 Beads for Protein Purification

We demonstrate a simple method to prepare poly(pentafluorophenyl acrylate) (poly(PFPA)) grafted silica beads for antibody immobilization and subsequent immunoprecipitation (IP) application. The poly(PFPA) grafted surface is prepared via a simple two-step process. In the first step, 3-aminopropyltrimethoxysilane (APTMS) is deposited as a linker molecule onto the silica surface. In the second step, poly(PFPA) homopolymer, synthesized via the reversible addition and fragmentation chain transfer (RAFT) polymerization, is grafted to the linker molecule through the exchange reaction between the pentafluorophenyl (PFP) units on the polymer and the amine groups on APTMS. The deposition of APTMS and poly(PFPA) on the silica particles are confirmed by X-ray photoelectron spectroscopy (XPS), as well as monitored by the particle size change measured via dynamic light scattering (DLS). To improve the surface hydrophilicity of the beads, partial substitution of poly(PFPA) with amine-functionalized poly(ethylene glycol) (amino-PEG) is also performed. The PEG-substituted poly(PFPA) grafted silica beads are then immobilized with antibodies for IP application. For demonstration, an antibody against protein kinase RNA-activated (PKR) is employed, and IP efficiency is determined by Western blotting. The analysis results show that the antibody immobilized beads can indeed be used to enrich PKR while non-specific protein interactions are minimal.

Preparation of Polypentafluorophenyl acrylate Functionalized SiO2 Beads for Protein Purification

A protocol for the preparation of poly(pentafluorophenyl acrylate) (poly(PFPA)) grafted silica beads is presented. The poly(PFPA) functionalized surface is then immobilized with antibodies and used successfully for the protein separation through immunoprecipitation.

蛋白質の浄化のため Poly(pentafluorophenyl acrylate) 機能 SiO2ビーズの準備

We demonstrate a simple method to prepare poly(pentafluorophenyl acrylate) (poly(PFPA)) grafted silica beads for antibody immobilization and subsequent ...

Iron Nanowire Fabrication by Nano-Porous Anodized Aluminum and its Characterization

Magnetic nanowires possess unique properties that have attracted the interest of different fields of research, including basic physics, biomedicine, and data storage. We demonstrate a fabrication method for iron (Fe) nanowires&#160;via electrochemical deposition into anodic&#160;alumina oxide (AAO) templates. The templates are fabricated by anodization of aluminum (Al) discs, and the pore length and diameter are controlled by changing the anodizing conditions. Pores with an average diameter of around 120 nm are created using oxalic acid as the electrolyte. Using this method, cylindrical nanowires are synthesized, which are released by dissolving the alumina using a selective chemical etchant.

In this work, we describe a&#160;protocol to fabricate iron nanowires, including the formation of the porous alumina membrane that is used as the template, electrodeposition into templates using electrolyte solution, and the release of the nanowires into the solution.

ナノ多孔質陽極酸化アルミニウムによる鉄ナノワイヤー製造とその特性

Magnetic nanowires possess unique properties that have attracted the interest of different fields of research, including basic physics, biomedicine, and ...