TCLは、王立協会研究助成金2016 R1(RG150551)およびEPSRCの機関スポンサーシップ賞(EP/P511262/1)を通じて資金提供されたUCL BEAMSフューチャーリーダー賞の支援に感謝しています。WIKC、TCL、IPPは、EPSRC M3S CDT(EP/L015862/1)を通じてA*STAR-UCL Research Attachment Programが資金提供している学生シップに感謝しています。GDとTJは、学生生活を支援してくれたEPSRC M3S CDT(EP/L015862/1)に感謝します。TJとTCLは、カムテック・イノベーションズがTJの学生生活に貢献したことを表彰します。すべての著者はUCLオープンアクセス基金に感謝しています。

1. Au NPの合成
<ol><li>従来のトルケビッチ法によるAu種子の合成26<ol>
<li>98.5 mgのHAuCl4·3H2O前駆体をガラスバイアル中の10mLの脱イオン水と共に使用する。 注:HAuCl 4前駆体は金属ラボウェアを腐食させるため、少量のHAuCl4前駆体を計量ボートに移し、金属ヘラの代わりにプラスチックヘラを使用して結晶を計量します。HAuCl4は吸湿性であり、したがって大気から水を吸収することによって時間の経過とともにその重量を増加させるので、計量ステップは可能な限り迅速に行われるべきである。HAuCl4は非常に腐食性であり、重度の皮膚火傷および眼の損傷を引き起こす可能性がある。取り扱いには特に注意してください。</li>
		<li>64.5mgのクエン酸ナトリウム粉末を0.5mLの脱イオン水でガラスバイアルに溶解して、0.5mLの500mMクエン酸ナトリウム溶液を調製する。</li>
		<li>250 mL の青い蓋付きボトルで 1 mL の 25 mM HAuCl 4 溶液を 99 mL の水で希釈し、100 mL の 0.25 mM HAuCl4 溶液を得た。</li>
		<li>99.5 mL の 0.25 mM HAuCl4 溶液を、コンデンサーを備えた 250 mL の三つ口ナスフラスコに加えます。激しく撹拌しながら溶液を90°Cに加熱し、温度を15分間維持する。</li>
		<li>500 mM クエン酸ナトリウム溶液 0.5 mL を反応混合物に注入し、溶液の色がルビーレッドに変わるまで温度と攪拌を維持する。 注:反応には約30分かかります。</li>
	</ol></li>
	<li>運動学的に制御された方法によるAu NPsの播種成長
	<ol>
<li>合成したAuシード溶液を70°Cに冷却する。</li>
		<li>154.8mgのクエン酸ナトリウム粉末を10mLの脱イオン水でガラスバイアルに溶解して、10mLの60mMクエン酸ナトリウム溶液を調製する。</li>
		<li>0.67 mL の 25 mM HAuCl4 溶液および 0.67 mL の 60 mM クエン酸ナトリウム溶液を 2 分間の時間間隔で Au 種子に注入します。</li>
		<li>手順 1.2.3 を繰り返して、Au NP のサイズを徐々に 40 nm まで増やします。 注:40nmに達するまでに約10の成長ステップが必要です。実際に必要なステップ数は、正確なセットアップに依存する場合があります。</li>
	</ol></li>
	<li>自動シンセサイザーを用いたAu NPの播種成長(図2)
	<ol>
<li>セクション1で調製したAuシード溶液25 mLを50 mL円錐遠心管に移し、サーモミキサーで70°Cまで冷却した。 メモ: 25 mL の水を含む 50 mL の遠沈管に入れた熱電対温度計を使用して、サーモミキサー内の温度を監視します。</li>
		<li>3 mL ルアーロック使い捨てシリンジに 2.5 mL の 25 mM HAuCl4 溶液を充填します。別の3 mLルアーロック使い捨てシリンジに2.5 mLの60 mMクエン酸ナトリウム溶液を充填します。</li>
		<li>シリンジをシリンジポンプに入れ、Luer-to-MicroTightアダプタを使用してPEEKチューブ(内径150μm)をシリンジに接続します。サーモミキサーでAuシード溶液を入れた遠沈管にチューブを挿入します。</li>
		<li>両方のシリンジポンプをセットして、0.1675 mL の溶液を 20 分間 (1 分あたり 8.357 μL) 分注します。</li>
		<li>サーモミキサーの回転数を 700 rpm に設定し、25 mM HAuCl4 溶液を含むシリンジポンプで Start を押します。</li>
		<li>2分後、60mMクエン酸ナトリウム溶液を含むシリンジポンプで 開始 を押します。</li>
		<li>HAuCl4溶液注入を開始してから30分後、分析のためにAu NP溶液のアリコートを除去する。</li>
		<li>手順 1.3.5 ~ 1.3.7 を繰り返して、Au NP の直径を 40 nm まで徐々に拡大します。 注: このセットアップは、ステップ 1.3.4 で添加される反応物の量を増やすことによって、Au NP を 1 ステップで最大 40 nm まで成長させるために使用できます。これは、同じ注入速度を維持しながら調剤時間を増加させることによって達成される。</li>
	</ol></li>
</ol>2. Au NPの特性評価
<ol><li>UV-Vis分光法<ol>
<li>1mLのAu NP溶液をセミマイクロ石英キュベットに加える。</li>
		<li>分光器をオンにします。</li>
		<li>波長範囲を 400 ~ 800 nm に設定します。</li>
		<li>各サンプルのUV-Visスペクトルを取得します。</li>
	</ol>
</li>
	<li>動的光散乱 (DLS)<ol>
<li>サンプル溶液を0.22μmフィルターでプラスチック製のセミマイクロキュベットにろ過します。</li>
		<li>DLS インストゥルメントをオンにします。</li>
		<li>温度を25°Cに設定し、60秒間平衡化します。</li>
		<li>各サンプルの流体力学的サイズを測定します。</li>
	</ol>
</li>
	<li>透過型電子顕微鏡(TEM)<ol>
<li>サンプル溶液の5 μLの液滴をCコーティングされた300メッシュCuグリッド上にドロップキャストし、空気中で乾燥させる。 注: TEM グリッド上に十分に分散した Au NP を得るためには、より濃縮された Au NP 溶液サンプルに希釈が必要です。</li>
		<li>200kVの加速電圧でTEMを使用して、サンプルごとに複数のTEM画像を取得します。</li>
		<li>ImageJを使用して各サンプルの200Au NPの直径を測定し、平均サイズと標準偏差を計算します。</li>
	</ol>
</li>
</ol>3. CB7-UA複合体の形成
<ol><li>0.4 mM CB7溶液の調製<ol>
<li>4.65mgのCB7を15mLのガラスバイアルに加える。 注:CB7の量は、文献中のほとんどの報告によって採用されているCB7の式重量(=1163Da)に基づいて計算される。それにもかかわらず、CB7固体サンプルは、典型的には、合成および精製ステップから残された水、HCl、メタノールおよび他の塩を含み、サンプル中の〜10〜20%の死重量に寄与する。捕捉された溶媒および塩は、真空オーブンまたは他の手段で加熱することによって除去することができなかった。それらの量はサンプルの異なるバッチ間で異なるが、元素分析を使用して定量化することができる。しかしながら、提示されたプロトコルは、CB7サンプル中の未定量量の溶媒および塩の存在に敏感ではない。</li>
		<li>バイアルに10mLの水を加え、キャップを締めます。</li>
		<li>CB7固体が完全に溶解するまで、室温でサンプルを超音波処理する。 注:CB7は文献27 に従って合成されたが、市販品でもある。</li>
	</ol>
</li>
	<li>0.4 mM UA溶液の調製<ol>
<li>2.69 mg の UA を 50 mL 遠沈管に加えます。</li>
		<li>チューブに40mLの水を加え、キャップを締めます。</li>
		<li>サーモミキサーを使用して、温度を70°C、速度を800rpm、時間を2時間に設定してサンプル溶液を旋回させます。溶液を室温まで冷却する。 注: UA は水への溶解度が低い (0.40 mM)5。UA粉末が完全に溶解していない場合は、より長く旋回する。あるいは、超音波処理は、溶解を容易にするために使用することができる。</li>
	</ol>
</li>
	<li>0.4 mM UA 溶液の逐次希釈<ol>
<li>5 mL の 0.4 mM UA 溶液を 15 mL のガラスバイアル中の 5 mL の水で希釈し、10 mL の 0.2 mM UA 溶液を得た。キャップを締め、30秒間超音波処理します。</li>
		<li>表 1 に記述されているように、適量の UA と水を使用して手順 3.3.1 を繰り返します。</li>
	</ol>
</li>
	<li>CB7-UA複合体の調製<ol>
<li>0.75 mL の 0.4 mM CB7 溶液および 0.75 mL の 0.4 mM UA 溶液を 1.5 mL チューブに加えます。蓋を固定し、30秒間超音波処理します。</li>
		<li>ホスト - ゲスト複合体の形成を確実にするために 30 分間待ちます。</li>
		<li>異なる濃度のUA溶液を使用して、ステップ3.4.1 - 3.4.2を繰り返します。</li>
	</ol>
</li>
</ol>4. UAのSERSセンシング
<ol><li>ラマンシステムの実験的セットアップ(図3)<ol>
<li>633 nm He-Neレーザー(22.5 mW)の電源を入れます。</li>
		<li>モジュラーラマン分光計の電源を入れます。</li>
		<li>コンピュータの電源を入れ、ソフトウェアを起動します。</li>
		<li>分光法アプリケーションウィザードアイコンをクリックし、ラマンを選択します。</li>
		<li>新しい取得を開始します。積分時間を 30 秒、スキャンを平均に 5、ボックスカーを 0 に設定します。</li>
		<li>バックグラウンドスペクトルを保存し、レーザー波長(すなわち、633nm)を入力します。 注:積分時間は各スキャンの時間であり、平均へのスキャンは各スペクトルを作成するために平均化されたスキャンの数であり、boxcarは平均28の隣接するピクセルの数である。</li>
	</ol>
</li>
	<li>SERS基板の形成<ol>
<li>0.9 mL の 40 nm Au NP 溶液および 0.1 mL の予備形成済み CB7-UA 複合体溶液を 1.5 mL チューブに加えます。蓋を固定し、溶液がルビーレッドからパープルに変わるまで超音波処理します。 注: 市販のクエン酸塩安定化 40 nm Au NP 溶液サンプルも使用できます。典型的には、局在型表面プラズモン共鳴(LSPR)ピークの光学密度は、濃縮原液試料からの希釈を介して1に調整される。試料中のクエン酸塩濃度は、典型的には2mMとして保持される。</li>
		<li>試料溶液をセミマイクロキュベットに移す。キュベットをラマンサンプルホルダーに入れ、カバーを閉じます。</li>
		<li>測定を開始します。</li>
		<li>5つの連続したSERSスペクトルを記録するように自動保存を設定します。</li>
		<li>測定を停止し、サンプルを変更します。</li>
		<li>異なる濃度のCB7-UA溶液を使用して、ステップ4.2.1 - 4.2.5を繰り返します。 注:凝集時間は、Au NPの凝集を媒介する大きな寄与を有する空のCB7の濃度の違いのために、0.1μM UAの30秒から20μM UAの30分の範囲のナノ凝集体中のUAの濃度に依存することが見出される。CB7−UA複合体の場合、1つのポータルはかさばるUA分子によって遮断され、Au NP表面への結合に利用できなくなり、したがってNP凝集21を媒介することができなくなる。溶液の色がルビーレッドからパープルに変わると、サンプルは測定の準備が整います。</li>
	</ol>
</li>
</ol>5. データ解析
<ol><li>データ処理<ol>
<li>非対称最小二乗法(ALS)プラグインを使用したベースラインをOriginにダウンロードしてインストールします。 メモ: ALS プラグインには OriginPro が必要です。</li>
		<li>生データを Origin に挿入します。</li>
		<li>各サンプルの5つのSERSスペクトルから平均値を算出する。レーザーのパワー(22.5mW)と積分時間(30秒)で値を割ります。</li>
		<li>ALS アイコンをクリックしてダイアログを開きます。非対称係数を 0.001、しきい値を 0.03%、平滑化係数を 2、反復回数を 20 に設定して、各平均スペクトルのベースラインを修正します。</li>
		<li>異なるUA濃度のSERSスペクトルを、yオフセットによる積み上げ線を使用してプロットします。出力は、ラマンシフト(cm-1)に対する強度(カウントs-1 mW-1)でなければなりません。</li>
	</ol>
</li>
</ol>

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A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Formation+of+Dynamic+Aggregates+in+Water+by+Cucurbit[5]uril+Capped+with+Gold+Nanoparticles.">Formation of Dynamic Aggregates in Water by Cucurbit[5]uril Capped with Gold Nanoparticles.</a> ChemComm. 46 (14), 2438-2440 (2010).</li><li>Lee, T. C., Scherman, O. 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+Facile+Synthesis+of+Dynamic+Supramolecular+Aggregates+of+Cucurbit[n]uril+(n+=+5-8)+Capped+with+Gold+Nanoparticles+in+Aqueous+Media.">A Facile Synthesis of Dynamic Supramolecular Aggregates of Cucurbit[n]uril (n = 5-8) Capped with Gold Nanoparticles in Aqueous Media.</a> Chemistry-A European Journal. 18 (6), 1628-1633 (2012).</li><li>Taylor, R. W., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Precise+Subnanometer+Plasmonic+Junctions+for+SERS+within+Gold+Nano-+particle+Assemblies+Using+Cucurbit[n]uril+"Glue".">Precise Subnanometer Plasmonic Junctions for SERS within Gold Nano- particle Assemblies Using Cucurbit[n]uril "Glue".</a> ACS Nano. 5 (5), 3878-3887 (2011).</li><li>Peveler, W. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cucurbituril-mediated+quantum+dot+aggregates+formed+by+aqueous+self-assembly+for+sensing+applications.">Cucurbituril-mediated quantum dot aggregates formed by aqueous self-assembly for sensing applications.</a> ChemComm. 55 (38), 5495-5498 (2019).</li><li>Chio, W. I. K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Selective+Detection+of+Nitroexplosives+Using+Molecular+Recognition+within+Self-Assembled+Plasmonic+Nanojunctions.">Selective Detection of Nitroexplosives Using Molecular Recognition within Self-Assembled Plasmonic Nanojunctions.</a> The Journal of Physical Chemistry C. 123 (25), 15769-15776 (2019).</li><li>Kasera, S., Biedermann, F., Baumberg, J. J., Scherman, O. A., Mahajan, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Quantitative+SERS+Using+the+Sequestration+of+Small+Molecules+Inside+Precise+Plasmonic+Nanoconstructs.">Quantitative SERS Using the Sequestration of Small Molecules Inside Precise Plasmonic Nanoconstructs.</a> Nano Letters. 12 (11), 5924-5928 (2012).</li><li>Taylor, R. W., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+Situ+SERS+Monitoring+of+Photochemistry+within+a+Nanojunction+Reactor.">In Situ SERS Monitoring of Photochemistry within a Nanojunction Reactor.</a> Nano Letters. 13 (12), 5985-5990 (2013).</li><li>Kasera, S., Herrmann, L. O., Barrio, J. d., Baumberg, J. J., Scherman, O. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Quantitative+Multiplexing+with+Nano-Self-Assemblies+in+SERS.">Quantitative Multiplexing with Nano-Self-Assemblies in SERS.</a> Scientific Reports. 4, 6785 (2014).</li><li>Chio, W. I. K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dual-triggered+nanoaggregates+of+cucurbit[7]uril+and+gold+nanoparticles+for+multi-spectroscopic+quantification+of+creatinine+in+urinalysis.">Dual-triggered nanoaggregates of cucurbit[7]uril and gold nanoparticles for multi-spectroscopic quantification of creatinine in urinalysis.</a> Journal of Materials Chemistry C. 8, 7051-7058 (2020).</li><li>Turkevich, J., Stevenson, P. C., Hillier, 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+study+of+the+nucleation+and+growth+processes+in+the+synthesis+of+colloidal+gold.">A study of the nucleation and growth processes in the synthesis of colloidal gold.</a> Discussions of the Faraday Society. 11, 55-75 (1951).</li><li>Lagona, J., Mukhopadhyay, P., Chakrabarti, S., Issacs, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+cucurbit[n]uril+family.">The cucurbit[n]uril family.</a> Angewandte Chemie International Edition. 44 (31), 4844-4870 (2005).</li><li>. OceanView Installation and Operation Manual Available from: <a target="_blank" href="https://www.oceaninsight.com/globalassets/catalog-blocks-and-images/manuals--instruction-old-logo/software/oceanviewio.pdf">https://www.oceaninsight.com/globalassets/catalog-blocks-and-images/manuals--instruction-old-logo/software/oceanviewio.pdf</a> (2013)</li><li>Mahajan, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Raman+and+SERS+spectroscopy+of+cucurbit[n]urils.">Raman and SERS spectroscopy of cucurbit[n]urils.</a> Physical Chemistry Chemical Physics. 12 (35), 10429-10433 (2010).</li><li>Langer, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Present+and+Future+of+Surface-Enhanced+Raman+Scattering.">Present and Future of Surface-Enhanced Raman Scattering.</a> ACS Nano. 14 (1), 28-117 (2020).</li><li>Pilot, R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Review+on+Surface-Enhanced+Raman+Scattering.">A Review on Surface-Enhanced Raman Scattering.</a> Biosensors. 9 (2), 57 (2019).</li><li>Bantz, K. C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recent+progress+in+SERS+biosensing.">Recent progress in SERS biosensing.</a> Physical Chemistry Chemical Physics. 13 (24), 11551-11567 (2011).</li><li>Moore, T. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+Vitro+and+In+Vivo+SERS+Biosensing+for+Disease+Diagnosis.">In Vitro and In Vivo SERS Biosensing for Disease Diagnosis.</a> Biosensors. 8 (2), 46 (2018).</li><li>Bonifacio, A., Cervo, S., Sergo, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Label-free+surface-enhanced+Raman+spectroscopy+of+biofluids:+fundamental+aspects+and+diagnostic+applications.">Label-free surface-enhanced Raman spectroscopy of biofluids: fundamental aspects and diagnostic applications.</a> Analytical and Bioanalytical Chemistry. 407 (27), 8265-8277 (2015).</li><li>Jeong, H. H., Choi, E., Ellis, E., Lee, T. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recent+advances+in+gold+nanoparticles+for+biomedical+applications:+from+hybrid+structures+to+multi-functionality.">Recent advances in gold nanoparticles for biomedical applications: from hybrid structures to multi-functionality.</a> Journal of Materials Chemistry B. 7 (22), 3480-3496 (2019).</li><li>Premasiri, W. R., Clarke, R. H., Womble, M. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Urine+Analysis+by+Laser+Raman+Spectroscopy.">Urine Analysis by Laser Raman Spectroscopy.</a> Lasers in Surgery and Medicine. 28 (4), 330-334 (2001).</li><li>Lu, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Superhydrophobic+silver+film+as+a+SERS+substrate+for+the+detection+of+uric+acid+and+creatinine.">Superhydrophobic silver film as a SERS substrate for the detection of uric acid and creatinine.</a> Biomedical Optics Express. 9 (10), 4988-4997 (2018).</li><li>Feig, D. I., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Serum+Uric+Acid:+A+Risk+Factor+and+a+Target+for+Treatment.">Serum Uric Acid: A Risk Factor and a Target for Treatment.</a> Journal of the American Society of Nephrology. 17 (4), 69-73 (2006).</li><li>Maiuolo, J., Oppedisano, F., Gratteri, S., Muscoli, C., Mollace, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Regulation+of+uric+acid+metabolism+and+excretion.">Regulation of uric acid metabolism and excretion.</a> International Journal of Cardiology. 213, 8-14 (2016).</li></ol>

著者らは開示するものは何もありません。

プロトコルに記載されている自動合成法により、サイズが増大するAu NPを再現性よく合成することができます。種子合成中のクエン酸ナトリウムの迅速な添加や、PEEKチューブが安全であることを確認するために定期的にチェックするなど、手動で行う必要がある要素がいくつかありますが、この方法は、通常、HAuCl 4およびクエン酸ナトリウムの複数回の手動注射を必要とする大きなサイズ(?...

プリンヌクレオチドの代謝の最終産物である尿酸は、痛風、子癇前症、腎疾患、高血圧、心血管疾患および糖尿病などの疾患の診断のための血清および尿中の重要なバイオマーカーである1,2,3,4,5。尿酸検出のための現在の方法には、比色酵素アッセイ、高速液体クロマトグラフィーおよびキャピラリー電気泳動が含まれるが、これらは時間がかかり、高価であり、洗練されたサンプル調製を必要とする6、7、8、9。
表面増強ラマン分光法は、振動指紋を介して生体分子を選択的に検出でき、高感度、迅速な応答、使いやすさ、サンプル調製がゼロまたは最小限に抑えられるなど、多くの利点を提供するため、日常的なポイントオブケア診断に有望な技術です。貴金属ナノ粒子(例えば、Au NPs)に基づくSERS基板は、表面プラズモン共鳴11によって引き起こされる強力な電磁増強を介して、分析物分子のラマンシグナルを4〜10桁10桁増強することができる。カスタマイズされたサイズのAu NPは、複雑な金属ナノコンポジット12の時間のかかる製造とは対照的に容易に合成することができ、したがって、その優れた特性13、14、15、16のために生物医学的用途において広く使用されている。大環状分子であるウリ科植物[n]urils(CBn、ここでn = 5-8, 10)をAu NPの表面上に付着させることで、高度に対称で剛直なCB分子がAu NP間の正確な間隔を制御し、ホスト-ゲスト複合体の形成を介してプラズモニックホットスポットの中心または近接する分析物分子を局在させることができるため、分析物分子のSERSシグナルをさらに高めることができます(図1)17、18,19,20。Au NP:CBnナノ凝集体を用いたSERS研究の以前の例には、ニトロ爆発物、多環芳香族化合物、ジアミノスチルベン、神経伝達物質およびクレアチニン21、22、23、24、25が含まれ、SERS測定はキュベット内で、またはカスタムメイドのサンプルホルダーに小さな液滴を装填することによって行われる。この検出スキームは、高い再現性で複雑なマトリックス中のバイオマーカーを迅速に定量するために特に有用である。
本明細書では、CB7と重要なバイオマーカーUAの宿主 - ゲスト複合体を形成し、水性媒体中のAu NPのCB7媒介凝集を介して0.2μMの検出限界を有するUAを定量するための容易な方法が、診断および臨床用途に有望であるモジュラー分光計を用いて実証された。

<table>
	<tbody>
		<tr>
			<td>40 nm gold nanoparticles</td>
			<td>NanoComposix</td>
			<td>AUCN40-100M</td>
			<td>NanoXact, 0.05 mg/ mL, bare (citrate)</td>
		</tr>
		<tr>
			<td>Centrifuge tube</td>
			<td>Corning Falcon</td>
			<td>14-432-22</td>
			<td>50 mL volume</td>
		</tr>
		<tr>
			<td>Cucurbit[7]uril</td>
			<td>Lab-made</td>
			<td></td>
			<td>see ref. 19</td>
		</tr>
		<tr>
			<td>Gold(III) chloride trihydrate</td>
			<td>Sigma aldrich</td>
			<td>520918</td>
			<td>&#8805;99.9% trace metals basis</td>
		</tr>
		<tr>
			<td>Luer lock disposable syringe</td>
			<td>Cole-Parmer</td>
			<td>WZ-07945-15</td>
			<td>3 mL volume</td>
		</tr>
		<tr>
			<td>Luer-to-MicroTight adapter</td>
			<td>LuerTight</td>
			<td>P-662</td>
			<td>360 &#956;m outer diameter Tubing to Luer Syringe</td>
		</tr>
		<tr>
			<td>PEEK tubing</td>
			<td>IDEX</td>
			<td>1572</td>
			<td>360 &#956;m outer diameter, 150 &#956;m inner diameter</td>
		</tr>
		<tr>
			<td>PEEK tubing cutter</td>
			<td>IDEX</td>
			<td>WZ-02013-30</td>
			<td>Capillary Polymer Chromatography Tubing Cutter For 360 &#181;m to 1/32&#34; OD tubing</td>
		</tr>
		<tr>
			<td>Raman spectrometer</td>
			<td>Ocean Optics</td>
			<td>QE pro</td>
			<td></td>
		</tr>
		<tr>
			<td>Sodium citrate tribasic dihydrate</td>
			<td>Sigma aldrich</td>
			<td>S4641</td>
			<td>ACS reagent, &#8805;99.0%</td>
		</tr>
		<tr>
			<td>Sonicator</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Standard Probe</td>
			<td>Digi-Sense</td>
			<td>WZ-08516-55</td>
			<td>Type-K</td>
		</tr>
		<tr>
			<td>Syringe pump</td>
			<td>Aladdin</td>
			<td>ALADDIN2-220</td>
			<td>2 syringes, maximum syringe volume 60 mL</td>
		</tr>
		<tr>
			<td>Thermocouple thermometer</td>
			<td>Digi-Sense</td>
			<td>WZ-20250-91</td>
			<td>Single-Input Thermocouple Thermometer with NIST-Traceable Calibration</td>
		</tr>
		<tr>
			<td>ThermoMixer</td>
			<td>Eppendorf</td>
			<td>5382000031</td>
			<td>With an Eppendorf SmartBlock for 50 mL tubes</td>
		</tr>
		<tr>
			<td>Uric acid</td>
			<td>Sigma aldrich</td>
			<td>U2625</td>
			<td>&#8805;99%, crystalline</td>
		</tr>
	</tbody>
</table>

quantitative sers detection of uric acid via formation of precise plasmonic nanojunctions within aggregates of gold nanoparticles and cucurbit[n]uril

この研究は、重要なバイオマーカーである尿酸(UA)を、指紋領域の複数の特徴的なピークに対して〜0.2μMの低い検出限界で表面増強ラマン分光法(SERS)を介して、モジュラー分光計を使用して定量的に検出するための迅速かつ高感度な方法を説明する。このバイオセンシングスキームは、大環状体、ウリ科植物[7]uril(CB7)、およびUAの間の宿主 - ゲスト複合体形成、およびその後の自己組織化Au NP:CB7ナノ集合体内の正確なプラズモニックナノ接合の形成によって媒介される。SERS基板にとって望ましいサイズの容易なAu NP合成も、ラボで構築された自動シンセサイザーを使用して容易にするオプションを備えた古典的なクエン酸還元アプローチに基づいて行われています。このプロトコルは、臨床応用のための体液中のバイオマーカーの多重化検出に容易に拡張することができる。

提示されたAu NP合成では、UV-Visスペクトルは10の成長ステップ後にLSPRピークの521nmから529nmへのシフトを示し(図4 A,B)、DLSデータはAu NPのサイズが25.9nmから42.8nmに増加するにつれて狭いサイズ分布を示す(図4C,D)。TEM画像から測定されたG0、G5、G10の平均サイズ(図4E)は、それぞれ20.1±2.1nm、32.5±2.3nm、40.0±2.2...

Watch this Scientific Journal Video about Quantitative SERS Detection of Uric Acid via Formation of Precise Plasmonic Nanojunctions within Aggregates of Gold Nanoparticles and Cucurbit[n]uril at JoVE.

Quantitative SERS Detection of Uric Acid via Formation of Precise Plasmonic Nanojunctions within Aggregates of Gold Nanoparticles and Cucurbit[n]uril

ウリ科植物[7]ウリルと尿酸のホスト-ゲスト複合体を水溶液中で形成した後、Au NP溶液に少量添加し、モジュール式分光計を用いた定量的表面増強ラマン分光法(SERS)センシングを行った。

金ナノ粒子とCucurbit[n]urilの凝集体内の正確なプラズモニックナノ接合の形成による尿酸の定量的SERS検出

This work describes a rapid and highly sensitive method for the quantitative detection of an important biomarker, uric acid (UA), via surface-enhanced ...

quantitative-sers-detection-uric-acid-via-formation-precise-plasmonic

Research

JoVE Journal

Chemistry

Quantitative SERS Detection of Uric Acid via Formation of Precise Plasmonic Nanojunctions within Aggregates of Gold Nanoparticles and Cucurbit[n]uril

3.8K ビュー.  University College London (UCL). ウリ科植物[7]ウリルと尿酸のホスト-ゲスト複合体を水溶液中で形成した後、Au NP溶液に少量添加し、モジュール式分光計を用いた定量的表面増強ラマン分光法(SERS)センシングを行った。

ビデオ: Quantitative SERS Detection of Uric Acid via Formation of Precise Plasmonic Nanojunctions within Aggregates of Gold Nanoparticles and Cucurbit[n]uril

Template Directed Synthesis of Plasmonic Gold Nanotubes with Tunable IR Absorbance

A nearly parallel array of pores can be produced by anodizing aluminum foils in acidic environments1, 2. Applications of anodic aluminum oxide (AAO) membranes have been under development since the 1990's and have become a common method to template the synthesis of high aspect ratio nanostructures, mostly by electrochemical growth or pore-wetting. Recently, these membranes have become commercially available in a wide range of pore sizes and densities, leading to an extensive library of functional nanostructures being synthesized from AAO membranes. These include composite nanorods, nanowires and nanotubes made of metals, inorganic materials or polymers 3-10. Nanoporous membranes have been used to synthesize nanoparticle and nanotube arrays that perform well as refractive index sensors, plasmonic biosensors, or surface enhanced Raman spectroscopy (SERS) substrates 11-16, as well as a wide range of other fields such as photo-thermal heating 17, permselective transport 18, 19, catalysis 20, microfluidics 21, and electrochemical sensing 22, 23. Here, we report a novel procedure to prepare gold nanotubes in AAO membranes. Hollow nanostructures have potential application in plasmonic and SERS sensing, and we anticipate these gold nanotubes will allow for high sensitivity and strong plasmon signals, arising from decreased material dampening 15.

Solution-suspendable gold nanotubes with controlled dimensions can be synthesized by electrochemical deposition in porous anodic aluminum oxide (AAO) membranes using a hydrophobic polymer core. Gold nanotubes and nanotube arrays hold promise for applications in plasmonic biosensing, surface-enhanced Raman spectroscopy, photo-thermal heating, ionic and molecular transport, microfluidics, catalysis and electrochemical sensing.

テンプレートには、調整可能な赤外線吸光度モニック金ナノチューブの合成を監督

A nearly parallel array of pores can be produced by anodizing aluminum foils in acidic environments1, 2. Applications of anodic aluminum oxide (AAO) ...

化学

Preparation of Silica Nanoparticles Through Microwave-assisted Acid-catalysis

Microwave-assisted synthetic techniques were used to quickly and reproducibly produce silica nanoparticle sols using an acid catalyst with nanoparticle diameters ranging from 30-250 nm by varying the reaction conditions. Through the selection of a microwave compatible solvent, silicic acid precursor, catalyst, and microwave irradiation time, these microwave-assisted methods were capable of overcoming the previously reported shortcomings associated with synthesis of silica nanoparticles using microwave reactors. The siloxane precursor was hydrolyzed using the acid catalyst, HCl. Acetone, a low-tan &#948; solvent, mediates the condensation reactions and has minimal interaction with the electromagnetic field. Condensation reactions begin when the silicic acid precursor couples with the microwave radiation, leading to silica nanoparticle sol formation. The silica nanoparticles were characterized by dynamic light scattering data and scanning electron microscopy, which show the materials&#39; morphology and size to be dependent on the reaction conditions. Microwave-assisted reactions produce silica nanoparticles with roughened textured surfaces that are atypical for silica sols produced by St&#246;ber&#39;s methods, which have smooth surfaces.

Silica nanoparticles were prepared using acid-catalysis of a siloxane precursor and microwave-assisted synthetic techniques resulting in the controlled growth of nanomaterials ranging from 30-250 nm in diameter. The growth dynamics can be controlled by varying the initial silicic acid concentration, time of the reaction, and temperature of reaction.

マイクロ波支援酸 - 触媒反応によりシリカナノ粒子の調製

Microwave-assisted synthetic techniques were used to quickly and reproducibly produce silica nanoparticle sols using an acid catalyst with nanoparticle ...

A Simple Method for the Size Controlled Synthesis of Stable Oligomeric Clusters of Gold Nanoparticles under Ambient Conditions

Reducing dilute aqueous HAuCl4 with sodium thiocyanate (NaSCN) under alkaline conditions produces 2 to 3 nm diameter nanoparticles. Stable grape-like oligomeric clusters of these yellow nanoparticles of narrow size distribution are synthesized under ambient conditions via two methods. The delay-time method controls the number of subunits in the oligoclusters by varying the time between the addition of HAuCl4 to alkaline solution and the subsequent addition of reducing agent, NaSCN. The yellow oligoclusters produced range in size from ~3 to ~25 nm. This size range can be further extended by an add-on method utilizing hydroxylated gold chloride (Na+[Au(OH4-x)Clx]-) to auto-catalytically increase the number of subunits in the as-synthesized oligocluster nanoparticles, providing a total range of 3 nm to 70 nm. The crude oligocluster preparations display narrow size distributions and do not require further fractionation for most purposes. The oligoclusters formed can be concentrated &#62;300 fold without aggregation and the crude reaction mixtures remain stable for weeks without further processing. Because these oligomeric clusters can be concentrated before derivatization they allow expensive derivatizing agents to be used economically. In addition, we present two models by which predictions of particle size can be made with great accuracy.

We describe a simple method for producing highly stable oligomeric clusters of gold nanoparticles via the reduction of chloroauric acid (HAuCl4) with sodium thiocyanate (NaSCN). The oligoclusters have a narrow size distribution and can be produced with a wide range of sizes and surface coats.

周囲条件下での金ナノ粒子の安定オリゴマークラスターのサイズ制御された合成のための簡単​​な方法

Reducing dilute aqueous HAuCl4 with sodium thiocyanate (NaSCN) under alkaline conditions produces 2 to 3 nm diameter nanoparticles. Stable grape-like ...

Synthesis of Ligand-free CdS Nanoparticles within a Sulfur Copolymer Matrix

Aliphatic ligands are typically used during the synthesis of nanoparticles to help mediate their growth in addition to operating as high-temperature solvents. These coordinating ligands help solubilize and stabilize the nanoparticles while in solution, and can influence the resulting size and reactivity of the nanoparticles during their formation. Despite the ubiquity of using ligands during synthesis, the presence of aliphatic ligands on the nanoparticle surface can result in a number of problems during the end use of the nanoparticles, necessitating further ligand stripping or ligand exchange procedures. We have developed a way to synthesize cadmium sulfide (CdS) nanoparticles using a unique sulfur copolymer. This sulfur copolymer is primarily composed of elemental sulfur, which is a cheap and abundant material. The sulfur copolymer has the advantages of operating both as a high temperature solvent and as a sulfur source, which can react with a cadmium precursor during nanoparticle synthesis, resulting in the generation of ligand free CdS. During the reaction, only some of the copolymer is consumed to produce CdS, while the rest remains in the polymeric state, thereby producing a nanocomposite material. Once the reaction is finished, the copolymer stabilizes the nanoparticles within a solid polymeric matrix. The copolymer can then be removed before the nanoparticles are used, which produces nanoparticles that do not have organic coordinating ligands. This nascent synthesis technique presents a method to produce metal-sulfide nanoparticles for a wide variety of applications where the presence of organic ligands is not desired.

Herein we present a method to synthesize ligand-free cadmium sulfide (CdS) nanoparticles based on a unique sulfur copolymer. The sulfur copolymer operates as a high temperature solvent and a sulfur source during the nanoparticle synthesis and stabilizes the nanoparticles after the reaction.

硫黄コポリマーマトリックス内リガンドフリーのCdSナノ粒子の合成

Aliphatic ligands are typically used during the synthesis of nanoparticles to help mediate their growth in addition to operating as high-temperature ...

An Optimized Protocol for the Efficient Radiolabeling of Gold Nanoparticles by Using a 125I-labeled Azide Prosthetic Group

Here, we demonstrate a detailed protocol for the radiosynthesis of a 125I-labeled azide prosthetic group and its application to the efficient radiolabeling of DBCO-group-functionalized gold nanoparticles using a copper-free click reaction. Radioiodination of the stannylated precursor (2) was carried out by using [125I]NaI and chloramine T as an oxidant at room temperature for 15 min. After HPLC purification of the crude product, the purified 125I-labeled azide (1) was obtained with high radiochemical yield (75 &plusmn; 10%, n = 8) and excellent radiochemical purity (&gt;99%). For the synthesis of radiolabeled 13-nm-sized gold nanoparticles, the DBCO-functionalized gold nanoparticles (3) were prepared by using a thiolated polyethylene glycol polymer. A copper-free click reaction between 1 and 3 gave the 125I-labeled gold nanoparticles (4) with more than 95% of radiochemical yield as determined by radio-thin-layer chromatography (radio-TLC). These results clearly indicate that the present radiolabeling method using a strain-promoted copper-free click reaction will be useful for the efficient and convenient radiolabeling of DBCO-group-containing nanomaterials.

An Optimized Protocol for the Efficient Radiolabeling of Gold Nanoparticles by Using a 125I-labeled Azide Prosthetic Group

A detailed procedure for the synthesis of a 125I-labeled azide and the radiolabeling of dibenzocyclooctyne (DBCO)-group-conjugated, 13-nm-sized gold nanoparticles using a copper-free click reaction is described.

使用した金ナノ粒子の効率的な放射性標識のために最適化されたプロトコル<sup&gt; 125</sup&gt; I標識アジド補綴グループ

Here, we demonstrate a detailed protocol for the radiosynthesis of a 125I-labeled azide prosthetic group and its application to the efficient ...

Luminophore Formation in Various Conformations of Bovine Serum Albumin by Binding of Gold(III)

The purpose of the presented protocols is to study the process of Au(III) binding to BSA, yielding conformation change-induced red fluorescence (&#955;em = 640 nm) of BSA-Au(III) complexes. The method adjusts the pH to show that the emergence of the red fluorescence is correlated with the pH-induced equilibrium transitions of the BSA conformations. Red fluorescent BSA-Au(III) complexes can only be formed with an adjustment of pH at or above 9.7, which corresponds to the &#34;A-form&#34; conformation of BSA. The protocol to adjust the BSA to Au molar ratio and to monitor the time-course of the process of Au(III) binding is described. The minimum number of Au(III) per BSA, to produce the red fluorescence, is less than seven. We describe the protocol in steps to illustrate the presence of multiple Au(III) binding sites in BSA. First, by adding copper (Cu(II)) or nickel (Ni(II)) cations followed by Au(III), this method reveals a binding site for Au(III) that is not the red fluorophore. Second, by modifying BSA by thiol capping agents, another nonfluorophore-forming Au(III) binding site is revealed. Third, changing the BSA conformation by cleaving and capping of the disulfide bonds, the possible Au(III) binding site(s) are illustrated. The protocol described, to control the BSA conformations and Au(III) binding, can be generally applied to study the interactions of other proteins and metal cations.

Luminophore Formation in Various Conformations of Bovine Serum Albumin by Binding of GoldIII

The protocols for studying the binding of gold cations (Au(III)) to various conformations of bovine serum albumin (BSA) as well as for characterizing the conformational dependent unique BSA-Au fluorescence are presented.

Luminophore 金の結合によるウシ血清アルブミンの様々 な立体構造の形成

The purpose of the presented protocols is to study the process of Au(III) binding to BSA, yielding conformation change-induced red fluorescence (&#955;em ...

Synthesis and Characterization of Amphiphilic Gold Nanoparticles

Gold nanoparticles covered with a mixture of 1-octanethiol (OT) and 11-mercapto-1-undecane sulfonic acid (MUS) have been extensively studied because of their interactions with cell membranes, lipid bilayers, and viruses. The hydrophilic ligands make these particles colloidally stable in aqueous solutions and the combination with hydrophobic ligands creates an amphiphilic particle that can be loaded with hydrophobic drugs, fuse with the lipid membranes, and resist nonspecific protein adsorption. Many of these properties depend on nanoparticle size and the composition of the ligand shell. It is, therefore, crucial to have a reproducible synthetic method and reliable characterization techniques that allow the determination of nanoparticle properties and the ligand shell composition. Here, a one-phase chemical reduction, followed by a thorough purification to synthesize these nanoparticles with diameters below 5 nm, is presented. The ratio between the two ligands on the surface of the nanoparticle can be tuned through their stoichiometric ratio used during synthesis. We demonstrate how various routine techniques, such as transmission electron microscopy (TEM), nuclear magnetic resonance (NMR), thermogravimetric analysis (TGA), and ultraviolet-visible (UV-Vis) spectrometry, are combined to comprehensively characterize the physicochemical parameters of the nanoparticles.

Amphiphilic gold nanoparticles can be used in many biological applications. A protocol to synthesize gold nanoparticles coated by a binary mixture of ligands and a detailed characterization of these particles is presented.

親和性金ナノ粒子の合成と特性化

Gold nanoparticles covered with a mixture of 1-octanethiol (OT) and 11-mercapto-1-undecane sulfonic acid (MUS) have been extensively studied because of ...

Assembly of Gold Nanorods into Chiral Plasmonic Metamolecules Using DNA Origami Templates

The inherent addressability of DNA origami structures makes them ideal templates for the arrangement of metal nanoparticles into complex plasmonic nanostructures. The high spatial precision of a DNA origami-templated assembly allows controlling the coupling between plasmonic resonances of individual particles and enables tailoring optical properties of the constructed nanostructures. Recently, chiral plasmonic systems attracted a lot of attention due to the strong correlation between the spatial configuration of plasmonic assemblies and their optical responses (e.g., circular dichroism [CD]). In this protocol, we describe the whole workflow for the generation of DNA origami-based chiral assemblies of gold nanorods (AuNRs). The protocol includes a detailed description of the design principles and experimental procedures for the fabrication of DNA origami templates, the synthesis of AuNRs, and the assembly of origami-AuNR structures. In addition, the characterization of structures using transmission electron microscopy (TEM) and CD spectroscopy is included. The described protocol is not limited to chiral configurations and can be adapted for the construction of various plasmonic architectures.

We describe the detailed protocol for the DNA origami-based assembly of gold nanorods into chiral plasmonic metamolecules with strong chiroptical responses. The protocol is not limited to chiral configurations and can be easily adapted for the fabrication of various plasmonic architectures.

DNA 折り紙テンプレートを用いたカイラル プラズモニック Metamolecules に金ナノロッドのアセンブリ

The inherent addressability of DNA origami structures makes them ideal templates for the arrangement of metal nanoparticles into complex plasmonic ...

Performing Spectroscopy on Plasmonic Nanoparticles with Transmission-Based Nomarski-Type Differential Interference Contrast Microscopy

Differential interference contrast (DIC) microscopy is a powerful imaging tool that is most commonly employed for imaging microscale objects using visible-range light. The purpose of this protocol is to detail a proven method for preparing plasmonic nanoparticle samples and performing single particle spectroscopy on them with DIC microscopy. Several important steps must be followed carefully in order to perform repeatable spectroscopy experiments. First, landmarks can be etched into the sample substrate, which aids in locating the sample surface and in tracking the region of interest during experiments. Next, the substrate must be properly cleaned of debris and contaminants that can otherwise hinder or obscure examination of the sample. Once a sample is properly prepared, the optical path of the microscope must be aligned, using Kohler Illumination. With a standard Nomarski style DIC microscope, rotation of the sample may be necessary, particularly when the plasmonic nanoparticles exhibit orientation-dependent optical properties. Because DIC microscopy has two inherent orthogonal polarization fields, the wavelength-dependent DIC contrast pattern reveals the orientation of rod-shaped plasmonic nanoparticles. Finally, data acquisition and data analyses must be carefully performed. It is common to represent DIC-based spectroscopy data as a contrast value, but it is also possible to present it as intensity data. In this demonstration of DIC for single particle spectroscopy, the focus is on spherical and rod-shaped gold nanoparticles.

The goal of this protocol is to detail a proven approach for the preparation of plasmonic nanoparticle samples and for performing single particle spectroscopy on them with differential interference contrast (DIC) microscopy.

トランスミッションベースのノマルスキー型差動干渉造影顕微鏡を用いたプラズモニックナノ粒子の分光法の実行

Differential interference contrast (DIC) microscopy is a powerful imaging tool that is most commonly employed for imaging microscale objects using ...

Synthesis of Aptamer-PEI-g-PEG Modified Gold Nanoparticles Loaded with Doxorubicin for Targeted Drug Delivery

Due to drug resistance and toxicity in healthy cells, use of doxorubicin (DOX) has been limited in clinical cancer therapy. This protocol describes the designing of poly(ethylenimine) grafted with polyethylene glycol (PEI-g-PEG) copolymer functionalized gold nanoparticles (AuNPs) with loaded aptamer (AS1411) and DOX through amide reactions. AS1411 is specifically bonded with targeted nucleolin receptors on cancer cells so that DOX targets cancer cells instead of healthy cells. First, PEG is carboxylated, then grafted to branched PEI to obtain a PEI-g-PEG copolymer, which is confirmed by 1H NMR analysis. Next, PEI-g-PEG copolymer coated gold nanoparticles (PEI-g-PEG@AuNPs) are synthesized, and DOX and AS1411 are covalently bonded to AuNPs gradually via amide reactions. The diameter of the prepared AS1411-g-DOX-g-PEI-g-PEG@AuNPs is ~39.9 nm, with a zeta potential of -29.3 mV, indicating that the nanoparticles are stable in water and cell medium. Cell cytotoxicity assays show that the newly designed DOX loaded AuNPs are able to kill cancer cells (A549). This synthesis demonstrates the delicate arrangement of PEI-g-PEG copolymers, aptamers, and DOX on AuNPs that are achieved by sequential amide reactions. Such aptamer-PEI-g-PEG functionalized AuNPs provide a promising platform for targeted drug delivery in cancer therapy.

In this protocol, doxorubicin-loaded AS1411-g-PEI-g-PEG modified gold nanoparticles are synthesized via three-step amide reactions. Then, doxorubicin is loaded and delivered to target cancer cells for cancer therapy.

標的薬物送達のためのドキソルビシンを装填したアプタマー-PEI-G-PEG改変金ナノ粒子の合成

Due to drug resistance and toxicity in healthy cells, use of doxorubicin (DOX) has been limited in clinical cancer therapy. This protocol describes the ...