This research was supported by the "Development of technologies for safety evaluation and standardization of nanomaterials and nanoproducts" (10059135)" through the Korea Evaluation Institute of Industrial Technology by the Korean Ministry of Trade, Industry &amp; Energy.

楽器や標本の作製<ol><li> Abrasor <ol><li> 80回転 - 摩耗試験機に基づいて、1試料回転ステージ（140ミリメートル径）とabrasor、2摩耗輪ホルダー、および30の回転速度を使用します。 </li><li>また、試験片に荷重を加える摩耗輪ホルダーに摩耗輪を確保するために重みを使用します。 </li><li> 図3に示すように、abrased粒子のためのより良いサスペンションを提供するために、追加の空気入口をインストールします。上記の15ミリメートルと40ミリメートル離れた試験片の中心部から位置して1/8 &quot;-diameterチューブを使用してください。 </li></ol></li><li> 摩耗輪 <ol><li>サンドペーパー（100グリットと真新しい）に摩耗輪（13ミリメートル、厚さ55ミリメートルの直径を、）ラップ。 </li></ol></li><li> 検体 <ol><li>試料は、摩耗試験のためのナノ材料を含む複合体です。 abrasorに設置し、試料はウィット準備する必要がありますへH 140ミリメートル径。 </li></ol></li><li> 室 <ol><li>静電気力によるパーティクル付着を回避するために、チャンバ壁のためにステンレス鋼を使用してください。室（容積1メートル3）（ 表1）の内部abrasorを置き、それぞれ、チャンバーの上部と下部に空気の入口と出口を探します。均一に混合粒子の流れを達成するために、空気の出口で、3多孔板からなる、ミキサーを使用してください。 </li></ol></li><li> 中和剤 <ol><li>静電荷電粒子がチャンバ壁上の粒子の付着を向上させるように、粒子の帯電状態を最小限にするために、中和剤（軟X線イオナイザ）を使用します。 </li></ol></li><li> オンライン測定器12、13 <ol><li>製造者の指示に従って、粒子数濃度及び粒度分布を測定するためのCPCとOPCを使用します。 </li><li> outleでCPCとOPCをインストールチャンバのtは粒子数濃度及び粒度分布を測定しました。 </li></ol></li><li> パーティクルサンプリング機器 <ol><li>粒子形態および構成要素を分析するフィルタ媒体を含む粒子サンプラまたはTEMグリッドを使用して放出された粒子をサンプリングします。 </li><li>放出粒子の形態を分析するために、チャンバの出口にフィルター媒体またはTEMグリッドを含む粒子サンプラーをインストールします。 </li></ol></li></ol>商工会議システムを用いたナノ粒子リリース2.摩耗試験注：摩耗試験条件を表2に記載されています。 <ol><li>室内の中央にabrasorを探します。 </li><li> abrasorの試料回転ステージ上に試験片を取り付けます。 </li><li>試験片に荷重を適用するために千グラムの重量で摩耗輪ホルダー内の摩耗車輪を固定します。 </li><li>中和剤（軟X線イオナイザ）を見つけます離れて45°の角度で試験片の中心28 cmであり、チャンバ壁上の静電粒子の沈着を減少させるために、 図2に見られるように。 注：中和剤は、ビーム露光により静電力を除去します。空気入口と摩耗輪は試料回転ステージ上に配置されているので、これは、試験片の表面に中和剤ビームのアクセスを制限します。したがって、中和剤は、ビームができるだけ試料表面の多くを達することができるように斜めに配置されています。 </li><li> 50リットル/分の流量でチャンバの出口に設置さ送風機を操作します。 </li><li>サプライ25 L /分の追加の空気入口から空気圧縮機を使用して、追加の粒子を含まないサスペンションの空気。 注：摩耗によって生成される粒子は、強く、試料及び摩耗ホイールの表面上に堆積させました。したがって、abrased粒子を測定することは困難です。追加の空気入口は、HELができます粒子懸濁液にこの問題を解決するために、P。 </li><li> 図4で説明したように、CPCを使用して1以下の＃/ ccでの1時間の平均粒子数濃度に到達するためにチャンバ内のバックグラウンド粒子数濃度を確認してください。 </li><li>千回転で72 rpmで試料回転ステージを回転させるステップモータを使用してabrasorの試料回転ステージを操作します。 </li><li>測定し、CPCとOPCを使用してリリースし、粒子数濃度と粒度分布を記録します。 注：ナノ複合材料から放出された粒子が懸濁し、圧送された空気によって運ばれます。これらの懸濁粒子は、最終的に気流以下の出口へ輸送されます。放出された粒子は、次いで、チャンバーの出口におけるCPCとOPCによって検出されます。 OPCはまた、粒度分布を測定することができながら、CPCとOPCは、最も頻繁に、粒子個数濃度を測定するために使用されます。 </li><li> SAMPルフィルター媒体またはTEMグリッドを含む粒子サンプラーを使用して放出された粒子。 注：気流以下室の出口に摩耗移動によってナノ複合材料から放出された粒子。チャンバーの出口で、放出された粒子は、粒子サンプラーを使用してサンプリングすることができます。フィルタ媒体又はTEMグリッド上に収集され放出された粒子は、次いで、TEMまたはSEM（走査型電子顕微鏡）を用いて分析することができます。 </li><li>粒子数濃度は、以下のピークの粒子数濃度の0.1％に達したときに測定し、サンプリングを停止します。 </li><li>すべてのデータ（CPC、OPC）を保存し、すべてのサンプル（試験片）を取り外します。 </li><li>各テストのための新しい標本と新しい磨耗ホイールを使用し、チャンバーを洗浄し、再現性を確認するために、各摩耗試験後キムワイプとIPA（イソプロピルアルコール）でabrasor。 </li></ol>

<ol>
	<li>Froggett, S. J., Clancy, S. F., Boverhof, D. R., Canady, R. 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+review+and+perspectives+of+existing+research+on+the+release+of+nanomaterials+from+solid+nanocomposites.">A review and perspectives of existing research on the release of nanomaterials from solid nanocomposites.</a> Part Fibre Toxicol. 11, (2014).</li><li>Kingston, C., Zepp, R., Andrady, A., Boverhof, D., Fehir, R., Hawkins, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Release+characteristics+of+selected+carbon+nanotube+polymer+composites.">Release characteristics of selected carbon nanotube polymer composites.</a> Carbon. 68, 33-57 (2014).</li><li>Kaiser, D., Stefaniak, A., Scott, K., Nguyen, T., Schutz, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Methods for the Measurement of Release of MWCNTs from MWCNT-Polymer Composites, NIST. , (2014).</li><li>Nowack, B., David, R. M., Fissan, H., Morris, H., Shatkin, J. A., Stintz, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Potential+release+scenarios+for+carbon+nanotubes+used+in+composites.">Potential release scenarios for carbon nanotubes used in composites.</a> Environ. Int. 59, 1-11 (2013).</li><li>Kim, E., Lee, J. H., Kim, J. K., Lee, G. H., Ahn, K., Park, J. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Case+Study+on+Risk+Evaluation+of+Silver+Nanoparticle+Exposure+from+Antibacterial+Sprays+Containing+Silver+Nanoparticles.">Case Study on Risk Evaluation of Silver Nanoparticle Exposure from Antibacterial Sprays Containing Silver Nanoparticles.</a> J of Nanomaterial. , 346586 (2015).</li><li>Kim, E., Lee, J. H., Kim, J. K., Lee, G. H., Ahn, K., Park, J. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Case+study+on+risk+evaluation+of+printed+electronics+using+nanosilver+ink.">Case study on risk evaluation of printed electronics using nanosilver ink.</a> Nano Convergence. , (2016).</li><li>Vorbau, M., Hillemann, L., Stintz, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Method+for+the+characterization+of+the+abrasion+induced+nanoparticle+release+into+air+from+surface+coatings.">Method for the characterization of the abrasion induced nanoparticle release into air from surface coatings.</a> J. Aerosol Sci. 40, 209-217 (2009).</li><li>Golanski, L., Gaborieau, A., Guiot, A., Uzu, G., Chatenet, J., Tardif, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characterization+of+abrasion-induced+nanoparticle+release+from+paints+into+liquids+and+air.">Characterization of abrasion-induced nanoparticle release from paints into liquids and air.</a> J. Phys. Conf. Ser. 304, 012062 (2011).</li><li>Wohlleben, W., Brill, S., Meier, M. W., Mertler, M., Cox, G., Hirth, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=On+the+lifecycle+of+nanocomposites:+Comparing+released+fragments+and+their+in-vivo+hazards+from+three+release+mechanisms+and+four+nanocomposites.">On the lifecycle of nanocomposites: Comparing released fragments and their in-vivo hazards from three release mechanisms and four nanocomposites.</a> Small. 7, 2384-2395 (2011).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> ISO 7784-1, Paints and varnishes -- Determination of resistance to abrasion -- Part 1: Rotating abrasive-paper-covered wheel method. , (1997).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> ISO 5470-1, Rubber- or plastics-coated fabrics -- Determination of abrasion resistance -- Part 1: Taber abrader. , (1999).</li><li>Schlagenhauf, L., Chu, B. T. T., Buha, J., N&#252;sch, F., Wang, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Release+of+carbon+nanotubes+from+an+epoxy-based+nanocomposites+during+an+abrasion+process.">Release of carbon nanotubes from an epoxy-based nanocomposites during an abrasion process.</a> Enviorn. Sci. Tech. 46, 7366-7372 (2012).</li><li>Bello, D., Wardle, B. L., Yamamoto, N., deVilloria, R. G., Garcia, E. J., Hart, A. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Exposure+to+nanoscale+particles+and+fibers+during+machining+of+hybrid+advanced+composites+containing+carbon+nanotubes.">Exposure to nanoscale particles and fibers during machining of hybrid advanced composites containing carbon nanotubes.</a> J. Nanopart. Res. 11, 231-249 (2009).</li><li>Cena, L. G., Peters, T. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characterization+and+control+of+airborne+particles+emitted+during+production+of+epoxy/carbon+nanotube+nanocomposites.">Characterization and control of airborne particles emitted during production of epoxy/carbon nanotube nanocomposites.</a> J. Occup. Environ. Hyg. 8, 86-92 (2011).</li></ol>

The authors have nothing to disclose.

摩耗試験を使用して、ナノ複合材料からnanorelease試験を行う最も重要なステップであった：1）摩耗によって生じる静電荷を除去し、チャンバ壁上の粒子の堆積を減少させるために中和剤を用いてステンレス鋼製のチャンバーシステムを使用して、 2）優れた粒子懸濁液を提供するために、追加の空気を供給する。 3）放出された粒子をサンプリングし、オンライン3多孔板からなるミキサーを?...

消費者の暴露が広く研究されていないながら、ナノ材料の暴露は主に、取り扱い製造、およびナノ材料をパッケージ化、製造職場の労働者との関係で研究されています。ナノテクノロジーの国際評議会（ICON）によって作成された環境と健康に関する文献データベースの最近の分析はまた、ほとんどのナノ材料の安全性の研究を表す、ナノコンポジットからのリリースでは、危険性（83％）と潜在的な暴露（16％）に集中していることが示されましたわずか0.8％1を表す消費者暴露、。このように、非常に小さなナノ材料への消費者ばく露について知られています。 ナノ粒子の放出は、ナノ複合材料、洗濯織物、またはこのような回転ドラム法、振盪、ボルテックス、及び他のシェーカー法2-3発塵試験方法の摩耗や耐候含むシミュレーション研究において、消費者の曝露を推定するために使用されてきました。さらに、いくつかの国際例えばILSI（国際生命科学研究所）nanorelease及びEU NanoRegような試みは、消費者製品に使用されるナノ物質の放出を理解するための技術を開発するために行われています。 2011年に発売ILSI nanoreleaseの消費者製品は、フェーズ1は、ナノ材料の選択を含む消費者製品からのナノ材料のリリースにライフサイクルアプローチを表し、フェーズ2は、評価方法をカバーし、フェーズ3は、施設間研究を実装しています。消費者製品中のナノ物質の安全性に関するいくつかの研究論文や出版物も4-6を公開されています。 一方、NanoRegは工業的ナノ物質の規制試験に欧州共通のアプローチを表し、シミュレーションで使用するための方法のプログラムを提供しても、消費者の安全に関連する標準を開発し、新しいを提出しようとしている消費者製品2. ISO TC 229からnanoreleaseへのアプローチ消費者の安全のための作業項目提案。 OECD工業ナノ材料安全部会（workiナノ材料に党）、特にSG8（暴露評価と暴露緩和に関する運営グループを）ngの、最近将来の仕事の方向、特に消費者や環境暴露評価に関する調査を実施しました。したがって、これらの国際的な活動、展覧会の韓国省庁の光の中で、産業資源は、「安全性評価やナノ材料やナノ製品の標準化のための技術の開発」に焦点を当て、2013年に階層プロジェクトを立ち上げました。さらに、消費者製品からのナノ物質の放出を標準化するには、いくつかの消費者の安全に関連する研究も7-8を公開されています。 摩耗試験は、様々な商業複合製品からのナノ粒子の潜在的な発光レベルを決定するためのILSIのnanoreleaseとNanoReg 2-3に含まれるシミュレーション手法の一つです。質量減量はabras前後の試料重量の差に基づいて推定されていますabrasorを用いたイオン。ナノ複合材料試料を一定速度で研磨され、サンプラーは、エアロゾルを吸引し、粒子は、その後、凝縮粒子カウンタ（CPC）または光学粒子計数器（OPC）などの粒子計数装置を用いて分析し、そしてTEMで収集されさらなる視覚分析のために（透過電子顕微鏡）グリッド又は膜。しかし、ナノ複合材料のための摩耗試験を実施することにより、耐摩耗性とするとき、粒子のサンプリングが発光点2-3、9-11付近で行われているの結果として、帯電粒子に困難である、一貫性のナノ粒子の放出を必要とします。 そこで、本稿では、ナノ複合材料の摩耗した場合のナノ材料の放出を評価するための新しい方法として、チャンバシステムを提供します。他の摩耗やシミュレーションテストと比較すると、提案されたチャンバシステムは、摩耗した場合の一貫性のあるナノ粒子の放出データを提供します。また、この新たな試験方法総粒子数計数法として室内空気質、半行動産業の分野で広く用いられている12、13。したがって、提案手法は含む消費者製品から試験ナノ粒子の放出のための標準化された方法へと発展することができることが予想されますナノ材料。

<table><tbody><tr><td>Foamex</td><td>Taeyoung, R. of Korea</td><td></td><td></td></tr><tr><td>MWCNT (multiwalled carbon nanotube) composite</td><td>Hanwha, Incheon, R. of Korea</td><td></td><td>2% MWCNTs in low density polyethylene</td></tr><tr><td>Abrasion Paper</td><td>Derfos, R. of Korea</td><td>#100</td><td>100 grit sand paper</td></tr><tr><td>Condensation Particle Counter (CPC)</td><td>TSI Inc, Shoreview, MN</td><td>UCPC 3775</td><td></td></tr><tr><td>Optical Paritcle Counter (OPC)</td><td>Grimm, Ainring, Germany</td><td>1.109</td><td></td></tr><tr><td>Mini Particle Sampler</td><td>Ecomesure, Saclay, France</td><td></td><td></td></tr><tr><td>Quantifoil Holey Carbon Film</td><td>TED PELLA Inc. USA</td><td>1.2/1.3</td><td></td></tr><tr><td>Filter Holder</td><td></td><td></td><td>custom made</td></tr><tr><td>Polycarbonate Filter&amp;nbsp;</td><td>Millipore, USA</td><td>CAT No. GTTP02500</td><td></td></tr><tr><td>Soft X-ray Ionizer (Neutralizer)</td><td>SUNJE, R. of Korea</td><td>SXN-05U</td><td></td></tr><tr><td>Field Emission-Scanning Electron Microscope (FE-SEM)</td><td>Hitachi</td><td>S-4300</td><td></td></tr></tbody></table>

testing of nanoparticle release from a composite containing nanomaterial using a chamber system

21世紀の最も重要な技術の一つとして、ナノテクノロジーの急速な発展に伴い、ナノ材料を含む消費者製品の安全性への関心も高まっています。ナノ物質を含む製品からのナノ材料の放出を評価することは、これらの製品の安全性を評価する上で重要なステップであり、ナノ材料のリリースの評価を標準化するための一貫性と信頼性の高い技術を開発するには、いくつかの国際的な努力をもたらしました。この研究では、ナノ材料を含む製品からナノ物質の放出は、凝縮粒子計数器、光学粒子計数器、及び電子顕微鏡分析用フィルタサンプルを収集するためのポートをサンプリングを含むチャンバーシステムを使用して評価されます。提案された室システムは、ナノ材料の放出が許容範囲内で再現可能と一貫しているかどうかを決定するためにabrasorディスク型ナノコンポジット材料の試験片を用いて試験されます。テスト結果は、各試験における粒子の総数は、いくつかの試行後の平均の20％以内であることを示しています。リリースの傾向は類似しており、彼らは非常に良い再現性を示しています。したがって、提案された室システムは、効果的にナノ物質を含む製品のナノ材料の放出試験のために使用することができます。

商工会議システムを用いた摩耗試験再現性 OPCは、1.98×10 9粒子（&gt; 0.3ミクロン）の平均値をカウントしながら、 表3に示すように全粒子数は、8摩耗試験のために一貫していた。CPCは、3.67×10 9粒子の平均値を測定しました。偏差は、摩耗時のパーティクルの一貫したリリースを表現する、20％以?...

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Testing of Nanoparticle Release from a Composite Containing Nanomaterial Using a Chamber System

Nanoparticle release is tested using a chamber system that includes a condensation particle counter, an optical particle counter and sampling ports to collect filter samples for microscopy analysis. The proposed chamber system can be effectively used for nanomaterial release testing with a repeatable and consistent data range.

商工会議システムを用いたナノ材料を含む複合からのナノ粒子のリリースのテスト

With the rapid development of nanotechnology as one of the most important technologies in the 21st century, interest in the safety of consumer products ...

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6.7K ビュー.  Hanyang University. Nanoparticle release is tested using a chamber system that includes a condensation particle counter, an optical particle counter and sampling ports to collect filter samples for microscopy analysis. The proposed chamber system can be effectively used for nanomaterial release testing with a repeatable and consistent data range.

ビデオ: Testing of Nanoparticle Release from a Composite Containing Nanomaterial Using a Chamber System

Optical Trapping of Nanoparticles

Optical trapping is a technique for immobilizing and manipulating small objects in a gentle way using light, and it has been widely applied in trapping and manipulating small biological particles. Ashkin and co-workers first demonstrated optical tweezers using a single focused beam1. The single beam trap can be described accurately using the perturbative gradient force formulation in the case of small Rayleigh regime particles1. In the perturbative regime, the optical power required for trapping a particle scales as the inverse fourth power of the particle size. High optical powers can damage dielectric particles and cause heating. For instance, trapped latex spheres of 109 nm in diameter were destroyed by a 15 mW beam in 25 sec1, which has serious implications for biological matter2,3.
A self-induced back-action (SIBA) optical trapping was proposed to trap 50 nm polystyrene spheres in the non-perturbative regime4. In a non-perturbative regime, even a small particle with little permittivity contrast to the background can influence significantly the ambient electromagnetic field and induce a large optical force. As a particle enters an illuminated aperture, light transmission increases dramatically because of dielectric loading. If the particle attempts to leave the aperture, decreased transmission causes a change in momentum outwards from the hole and, by Newton's Third Law, results in a force on the particle inwards into the hole, trapping the particle. The light transmission can be monitored; hence, the trap can become a sensor. The SIBA trapping technique can be further improved by using a double-nanohole structure.
The double-nanohole structure has been shown to give a strong local field enhancement5,6. Between the two sharp tips of the double-nanohole, a small particle can cause a large change in optical transmission, thereby inducing a large optical force. As a result, smaller nanoparticles can be trapped, such as 12 nm silicate spheres7 and 3.4 nm hydrodynamic radius bovine serum albumin proteins8. In this work, the experimental configuration used for nanoparticle trapping is outlined. First, we detail the assembly of the trapping setup which is based on a Thorlabs Optical Tweezer Kit. Next, we explain the nanofabrication procedure of the double-nanohole in a metal film, the fabrication of the microfluidic chamber and the sample preparation. Finally, we detail the data acquisition procedure and provide typical results for trapping 20 nm polystyrene nanospheres.

The following setup approach details low power optical trapping of dielectric nanoparticles using a double-nanohole in metal film.

ナノ粒子の光トラッピング

Optical trapping is a technique for immobilizing and manipulating small objects in a gentle way using light, and it has been widely applied in trapping ...

工学

Combinatorial Synthesis of and High-throughput Protein Release from Polymer Film and Nanoparticle Libraries

Polyanhydrides are a class of biomaterials with excellent biocompatibility and drug delivery capabilities. While they have been studied extensively with conventional one-sample-at-a-time synthesis techniques, a more recent high-throughput approach has been developed enabling the synthesis and testing of large libraries of polyanhydrides1. This will facilitate more efficient optimization and design process of these biomaterials for drug and vaccine delivery applications. The method in this work describes the combinatorial synthesis of biodegradable polyanhydride film and nanoparticle libraries and the high-throughput detection of protein release from these libraries. In this robotically operated method (Figure 1), linear actuators and syringe pumps are controlled by LabVIEW, which enables a hands-free automated protocol, eliminating user error. Furthermore, this method enables the rapid fabrication of micro-scale polymer libraries, reducing the batch size while resulting in the creation of multivariant polymer systems. This combinatorial approach to polymer synthesis facilitates the synthesis of up to 15 different polymers in an equivalent amount of time it would take to synthesize one polymer conventionally. In addition, the combinatorial polymer library can be fabricated into blank or protein-loaded geometries including films or nanoparticles upon dissolution of the polymer library in a solvent and precipitation into a non-solvent (for nanoparticles) or by vacuum drying (for films). Upon loading a fluorochrome-conjugated protein into the polymer libraries, protein release kinetics can be assessed at high-throughput using a fluorescence-based detection method (Figures 2 and 3) as described previously1. This combinatorial platform has been validated with conventional methods2 and the polyanhydride film and nanoparticle libraries have been characterized with 1H NMR and FTIR. The libraries have been screened for protein release kinetics, stability and antigenicity; in vitro cellular toxicity, cytokine production, surface marker expression, adhesion, proliferation and differentiation; and in vivo biodistribution and mucoadhesion1-11. The combinatorial method developed herein enables high-throughput polymer synthesis and fabrication of protein-loaded nanoparticle and film libraries, which can, in turn, be screened in vitro and in vivo for optimization of biomaterial performance.

This method describes the combinatorial synthesis of biodegradable polyanhydride film and nanoparticle libraries and the high-throughput detection of protein release from these libraries.

組合せの合成と高分子膜とナノ粒子のライブラリからのハイスループットタンパクリリース

Polyanhydrides are a class of biomaterials with excellent biocompatibility and drug delivery capabilities. While they have been studied extensively with ...

生物工学

Experimental Protocol to Investigate Particle Aerosolization of a Product Under Abrasion and Under Environmental Weathering

The present article presents an experimental protocol to investigate particle aerosolization of a product under abrasion and under environmental weathering, which is a fundamental element to the approach of nanosafety-by-design of nanostructured products for their durable development. This approach is basically a preemptive one in which the focus is put on minimizing the emission of engineered nanomaterials' aerosols during the usage phase of the product's life cycle. This can be attained by altering its material properties during its design phase without compromising with any of its added benefits. In this article, an experimental protocol is presented to investigate the nanosafety-by-design of three commercial nanostructured products with respect to their mechanical solicitation and environmental weathering. The means chosen for applying the mechanical solicitation is an abrasion process and for the environmental weathering, it is an accelerated UV exposure in the presence of humidity and heat. The eventual emission of engineered nanomaterials is studied in terms of their number concentration, size distribution, morphology and chemical composition. The purpose of the protocol is to study the emission for test samples and experimental conditions which are corresponding to real life situations. It was found that the application of the mechanical stresses alone emits the engineered nanomaterials' aerosols in which the engineered nanomaterial is always embedded inside the product matrix, thus, a representative product element. In such a case, the emitted aerosols comprise of both nanoparticles as well as microparticles. But if the mechanical stresses are coupled with the environmental weathering, the experimental protocol reveals then the eventual deterioration of the product, after a certain weathering duration, may lead to the emission of the free engineered nanomaterial aerosols too.

In this article, an experimental protocol to investigate particle aerosolization of a product under abrasion and under environmental weathering is presented. Results on the emission of engineered nanomaterials, in the form of aerosols are presented. The specific experimental set-up is described in detail.

摩耗の下で環境風化の下で製品の粒子エアロゾル化を調査するための実験プロトコール

The present article presents an experimental protocol to investigate particle aerosolization of a product under abrasion and under environmental ...

Evaluation of Polymeric Gene Delivery Nanoparticles by Nanoparticle Tracking Analysis and High-throughput Flow Cytometry

Non-viral gene delivery using polymeric nanoparticles has emerged as an attractive approach for gene therapy to treat genetic diseases1 and as a technology for regenerative medicine2. Unlike viruses, which have significant safety issues, polymeric nanoparticles can be designed to be non-toxic, non-immunogenic, non-mutagenic, easier to synthesize, chemically versatile, capable of carrying larger nucleic acid cargo and biodegradable and/or environmentally responsive. Cationic polymers self-assemble with negatively charged DNA via electrostatic interaction to form complexes on the order of 100 nm that are commonly termed polymeric nanoparticles. Examples of biomaterials used to form nanoscale polycationic gene delivery nanoparticles include polylysine, polyphosphoesters, poly(amidoamines)s and polyethylenimine (PEI), which is a non-degradable off-the-shelf cationic polymer commonly used for nucleic acid delivery1,3 . Poly(beta-amino ester)s (PBAEs) are a newer class of cationic polymers4 that are hydrolytically degradable5,6 and have been shown to be effective at gene delivery to hard-to-transfect cell types such as human retinal endothelial cells (HRECs)7, mouse mammary epithelial cells8, human brain cancer cells9 and macrovascular (human umbilical vein, HUVECs) endothelial cells10.
A new protocol to characterize polymeric nanoparticles utilizing nanoparticle tracking analysis (NTA) is described. In this approach, both the particle size distribution and the distribution of the number of plasmids per particle are obtained11. In addition, a high-throughput 96-well plate transfection assay for rapid screening of the transfection efficacy of polymeric nanoparticles is presented. In this protocol, poly(beta-amino ester)s (PBAEs) are used as model polymers and human retinal endothelial cells (HRECs) are used as model human cells. This protocol can be easily adapted to evaluate any polymeric nanoparticle and any cell type of interest in a multi-well plate format.

A protocol for nanoparticle tracking analysis (NTA) and high-throughput flow cytometry to evaluate polymeric gene delivery nanoparticles is described. NTA is utilized to characterize the nanoparticle particle size distribution and the plasmid per particle distribution. High-throughput flow cytometry enables quantitative transfection efficacy evaluation for a library of gene delivery biomaterials.

ナノ粒子トラッキング分析とハイスループットフローサイトメトリーによる高分子遺伝子デリバリーナノ粒子の評価

Non-viral gene delivery using polymeric nanoparticles has emerged as an attractive approach for gene therapy to treat genetic diseases1 and as a ...

Advanced Compositional Analysis of Nanoparticle-polymer Composites Using Direct Fluorescence Imaging

The fabrication of polymer-nanoparticle composites is extremely important in the development of many functional materials. Identifying the precise composition of these materials is essential, especially in the design of surface catalysts, where the surface concentration of the active component determines the activity of the material. Antimicrobial materials which utilize nanoparticles are a particular focus of this technology. Recently swell encapsulation has emerged as a technique for inserting antimicrobial nanoparticles into a host polymer matrix. Swell encapsulation provides the advantage of localizing the incorporation to the external surfaces of materials, which act as the active sites of these materials. However, quantification of this nanoparticle uptake is challenging. Previous studies explore the link between antimicrobial activity and surface concentration of the active component, but this is not directly visualized. Here we show a reliable method to monitor the incorporation of nanoparticles into a polymer host matrix via swell encapsulation. We show that the surface concentration of CdSe/ZnS nanoparticles can be accurately visualized through cross-sectional fluorescence imaging. Using this method, we can quantify the uptake of nanoparticles via swell encapsulation and measure the surface concentration of encapsulated particles, which is key in optimizing the activity of functional materials.

Here we present a reliable method to monitor the incorporation of nanoparticles into a polymer host matrix via swell encapsulation. We show that the surface concentration of cadmium selenide quantum dots can be accurately visualized through cross-sectional fluorescence imaging.

直接蛍光イメージングを用いたナノ粒子 - ポリマー複合材料の高度な組成分析

The fabrication of polymer-nanoparticle composites is extremely important in the development of many functional materials. Identifying the precise ...

A System to Create Stable Nanoparticle Aerosols from Nanopowders

Nanoparticle aerosols released from nanopowders in workplaces are associated with human exposure and health risks. We developed a novel system, requiring minimal amounts of test materials (min. 200 mg), for studying powder aerosolization behavior and aerosol properties. The aerosolization procedure follows the concept of the fluidized-bed process, but occurs in the modified volume of a V-shaped aerosol generator. The airborne particle number concentration is adjustable by controlling the air flow rate. The system supplied stable aerosol generation rates and particle size distributions over long periods (0.5-2 hr and possibly longer), which are important, for example, to study aerosol behavior, but also for toxicological studies. Strict adherence to the operating procedures during the aerosolization experiments ensures the generation of reproducible test results. The critical steps in the standard protocol are the preparation of the material and setup, and the aerosolization operations themselves. The system can be used for experiments requiring stable aerosol concentrations and may also be an alternative method for testing dustiness. The controlled aerosolization made possible with this setup occurs using energy inputs (may be characterized by aerosolization air velocity) that are within the ranges commonly found in occupational environments where nanomaterial powders are handled. This setup and its operating protocol are thus helpful for human exposure and risk assessment.

We designed and developed an effective nanopowder aerosolization setup and operating protocol. The system generated nanoparticle aerosols with stable number concentrations and size distributions for long durations, requiring only small quantities of test material (min. 200 mg).

ナノ粉末から安定したナノ粒子のエアロゾルを作成するシステム

Nanoparticle aerosols released from nanopowders in workplaces are associated with human exposure and health risks. We developed a novel system, requiring ...

A Continuous-flow Photocatalytic Reactor for the Precisely Controlled Deposition of Metallic Nanoparticles

In this work, a novel photocatalytic reactor for the pulsed and controlled excitation of the photocatalyst and the precise deposition of metallic nanoparticles is developed. Guidelines for the replication of the reactor and its operation are provided in detail. Three different composite systems (Pt/graphene, Pt/TiO2, and Au/TiO2) with monodisperse and uniformly distributed particles are produced by this reactor, and the photodeposition mechanism, as well as the synthesis optimization strategy, are discussed. The synthesis methods and their technical aspects are described comprehensively. The role of the ultraviolet (UV) dose (in each excitation pulse) on the photodeposition process is investigated and the optimum values for each composite system are provided.

For a continuous and scalable synthesis of noble-metal-based nanocomposites, a novel photocatalytic reactor is developed and its structure, operation principles, and product quality optimization strategies are described.

金属ナノ粒子の正確に制御された沈着量の連続的な流れの光触媒反応

In this work, a novel photocatalytic reactor for the pulsed and controlled excitation of the photocatalyst and the precise deposition of metallic ...

化学

Development of a Nose-only Inhalation Toxicity Test Chamber That Provides Four Exposure Concentrations of Nano-sized Particles

Using a numerical analysis based on computerized fluid dynamics, a nose-only inhalation toxicity chamber with four different exposure concentrations is designed and validated for flow field uniformity and cross-contamination among the exposure ports for each concentration. The designed flow field values are compared with the measured values from exposure ports located horizontally and vertically. For this purpose, nanoscale sodium chloride particles are generated as test particles and introduced to the inhalation chamber to evaluate the cross-contamination and concentration maintenance among the chambers, for each concentration group. The results indicate that the designed multiconcentration inhalation chamber can be used in animal inhalation toxicity testing without cross-contamination among concentration groups. Moreover, the designed multiconcentration inhalation toxicity chamber can also be converted to a single-concentration inhalation chamber. Further testing with gas, organic vapor, or non-nanoscale particles will ensure the use of the chamber in the inhalation testing of other test articles.

A nose-only inhalation toxicity chamber capable of testing inhalation toxicity at four different exposure concentrations was designed and validated for flow field uniformity and cross-contamination between the exposure ports for each concentration. Here, we present a protocol to confirm that the designed chamber is effective for inhalation toxicity testing.

ナノサイズ粒子の 4 つの暴露濃度は、鼻専用の吸入毒性試験室の開発

Using a numerical analysis based on computerized fluid dynamics, a nose-only inhalation toxicity chamber with four different exposure concentrations is ...

Whole-Body Nanoparticle Aerosol Inhalation Exposures

Inhalation is the most likely exposure route for individuals working with aerosolizable engineered nano-materials (ENM). To properly perform nanoparticle inhalation toxicology studies, the aerosols in a chamber housing the experimental animals must have: 1) a steady concentration maintained at a desired level for the entire exposure period; 2) a homogenous composition free of contaminants; and 3) a stable size distribution with a geometric mean diameter &lt; 200 nm and a geometric standard deviation &sigma;g &lt; 2.5 5. The generation of aerosols containing nanoparticles is quite challenging because nanoparticles easily agglomerate. This is largely due to very strong inter-particle forces and the formation of large fractal structures in tens or hundreds of microns in size 6, which are difficult to be broken up. Several common aerosol generators, including nebulizers, fluidized beds, Venturi aspirators and the Wright dust feed, were tested; however, none were able to produce nanoparticle aerosols which satisfy all criteria 5.
A whole-body nanoparticle aerosol inhalation exposure system was fabricated, validated and utilized for nano-TiO2 inhalation toxicology studies. Critical components: 1) novel nano-TiO2 aerosol generator; 2) 0.5 m3 whole-body inhalation exposure chamber; and 3) monitor and control system. Nano-TiO2 aerosols generated from bulk dry nano-TiO2 powders (primary diameter of 21 nm, bulk density of 3.8 g/cm3) were delivered into the exposure chamber at a flow rate of 90 LPM (10.8 air changes/hr). Particle size distribution and mass concentration profiles were measured continuously with a scanning mobility particle sizer (SMPS), and an electric low pressure impactor (ELPI). The aerosol mass concentration (C) was verified gravimetrically (mg/m3). The mass (M) of the collected particles was determined as M = (Mpost-Mpre), where Mpre and Mpost are masses of the filter before and after sampling (mg). The mass concentration was calculated as C = M/(Q*t), where Q is sampling flowrate (m3/min), and t is the sampling time (minute). The chamber pressure, temperature, relative humidity (RH), O2 and CO2 concentrations were monitored and controlled continuously. Nano-TiO2 aerosols collected on Nuclepore filters were analyzed with a scanning electron microscope (SEM) and energy dispersive X-ray (EDX) analysis.
In summary, we report that the nano-particle aerosols generated and delivered to our exposure chamber have: 1) steady mass concentration; 2) homogenous composition free of contaminants; 3) stable particle size distributions with a count-median aerodynamic diameter of 157 nm during aerosol generation. This system reliably and repeatedly creates test atmospheres that simulate occupational, environmental or domestic ENM aerosol exposures.

A whole-body nanoparticle aerosol inhalation exposure facility was constructed for nano-sized titanium dioxide (TiO2) inhalation toxicology studies. This system provides nano-TiO2 aerosol test atmospheres that have: 1) a steady mass concentration; 2) a homogenous composition free of contaminants; and 3) a stable particle size distribution during aerosol generation.

全身ナノ粒子エアロゾル吸入暴露

Inhalation is the most likely exposure route for individuals working with aerosolizable engineered nano-materials (ENM). To properly perform nanoparticle ...

生物学

An Air-liquid Interface Bronchial Epithelial Model for Realistic, Repeated Inhalation Exposure to Airborne Particles for Toxicity Testing

For toxicity testing of airborne particles, air-liquid interface (ALI) exposure systems have been developed for in vitro tests in order to mimic realistic exposure conditions. This puts specific demands on the cell culture models. Many cell types are negatively affected by exposure to air (e.g., drying out) and only remain viable for a few days. This limits the exposure conditions that can be used in these models: usually relatively high concentrations are applied as a cloud (i.e., droplets containing particles, which settle down rapidly) within a short period of time. Such experimental conditions do not reflect realistic long-term exposure to low concentrations of particles. To overcome these limitations the use of a human bronchial epithelial cell line, Calu-3 was investigated. These cells can be cultured at ALI conditions for several weeks while retaining a healthy morphology and a stable monolayer with tight junctions. In addition, this bronchial model is suitable for testing the effects of repeated exposures to low, realistic concentrations of airborne particles using an ALI exposure system. This system uses a continuous airflow in contrast to other ALI exposure systems that use a single nebulization producing a cloud. Therefore, the continuous flow system is suitable for repeated and prolonged exposure to airborne particles while continuously monitoring the particle characteristics, exposure concentration, and delivered dose. Taken together, this bronchial model, in combination with the continuous flow exposure system, is able to mimic realistic, repeated inhalation exposure conditions that can be used for toxicity testing.

Described is the cell culture and exposure method of an in vitro bronchial model for realistic, repeated inhalation exposure to particles for toxicity testing.

毒性試験のための空気中の粒子への現実的な反復吸入暴露のための気管支上皮モデル

For toxicity testing of airborne particles, air-liquid interface (ALI) exposure systems have been developed for in vitro tests in order to mimic realistic ...