Bu araştırma çalışmaları Atomik Seviye Catalyst Tasarım, ABD Enerji Departmanı, Bilim, Ödül sayısı DE-SC0001058 altında Temel Enerji Bilimler Dairesi Başkanlığı tarafından finanse edilen bir Enerji Frontier Araştırma Merkezi Merkezi&#39;nin bir parçası olarak desteklenen ve aynı zamanda Yönetim Kurulu tarafından desteklenmektedir hibe ödül numarası LEQSF (2009-14)-EFRC-MAÇ ve LEDSF-EPS (2012)-OPT-IN-15 altında Vekaleti. MRCAT işlemleri Enerji Bakanlığı ve MRCAT üye kurumlar tarafından desteklenmektedir. ANL de Gelişmiş Foton Kaynak kullanımı, Sözleşme No: DE-AC02-06CH11357 altında ABD Enerji Departmanı, Fen Bilimleri, Temel Enerji Bilimler Dairesi Ofisi tarafından desteklenmektedir. Jtm için mali destek Atom verimli Kimyasal Dönüşümler Enstitüsü (İAİS), ABD Enerji Bakanlığı tarafından finanse edilen bir Enerji Frontier Araştırma Merkezi, Bilim Ofisi, Temel Enerji Bilimler Office&#39;in bir parçası olarak sağlandı.

Millifluidics set-up: 220 mm (L) x 2 mm (W) x 0.15 mm (Y) boyutlarında serpantin kanalları var Microplumbers Microsciences LLC, dan (polyester tereftalat polimerden yapılmış) bir millifluidic çip satın alın. Pompaya çip bağlamak için 0.25 mm ID boyutlarında, OD 1/16, FEP Boru kullanın. İki farklı deneyler için iki farklı pompalar kullanarak. İlk deneyde (bakır nanopartikülleri) ve ikinci deney (altın nanopartiküller) için millifluidic cihaz için kullanın P-Pompa. , Kanalların içinde gaz kabarcıklarının problemi en aza indirmek için, yeni hazırlanmış bir NaBH4 solüsyonu, gaz kabarcıkları çözelti kaçmak böylece yonga içine pompalama önce ~ 10-15 dakika boyunca beklemeye açık bırakıldı. Bu adım bizim deneyler için tüm izledi. 1.. Ultra-küçük Bakır Nano Kümeler (UCNCs) sentezi <ol><li> Gerekli Kimyasallar: bakır elde (II) nitrate hidrat, sodyum borohidrid, sodyum hidroksit peletleri ve O-[2 - (3-mercaptopropionylamino) etil]-O&#39;-metilpolietilen glikol (MW = 5,000) [MPEG] ve daha fazla arıtılmadan tüm kimyasal kullanımı. Deney için nanopure su (M 18.2 cm) kullanın. </li><li> Kullanım P-Pompa deney için azot basıncı altında düzenlenmiştir. Karşılık gelen akış oranı (ml / s) ile ilişkili önce deney için farklı basınçlarda çözücü olarak su ile pompalar edin. Deneyin başlamasından önce deiyonize su ile millifluidic reaktör ve boru durulayın. </li><li> Bakır ve 174 mg (0.95 mmol) çözündürülür (II) nitrat ve O-[2 - (3-mercaptopropionylamino) etil] 610 mg (0.122 mmol) bir in-O&#39;-metilpolietilen nanopure 28 ml su içinde tutmak glikol ve bunların bir giriş kanalı ile bağlanacak şişe </li><li> Farklı bir şişe içinde bir sodyum borohidrit çözeltisi 111 mg (2.93 mmol) ve 102 mg (2.78 mmol) 28 ml sodyum hidroksit (pH ~ 13) tutun ve ile bağlamakDiğer giriş kanalı. </li><li> Farklı akış hızları (aşağıda verilmiştir) de millifluidic reaktör içinde aynı anda her iki çözüm akış ve bir cam şişe içinde çıkışında elde edilen UCNCs toplar. Azot ile temizleyin ve bu çözelti, azot altında depolanır. </li><li> Sentezi için, oda sıcaklığında 50 mbar (6.81 ml / saat), 100 mbar (14.31 ml / saat), 200 mbar (32.7 ml / saat) ve 300 mbar (51.4 ml / saat) farklı sabit basınçlar altında pompaları çalıştırın farklı akış hızlarında UCNCs. </li></ol> Sentez prosedürü P-pompa ile millifluidic düzen kullanılarak gösterilmiştir, aynı zamanda Millifluidica gelen el millifluidic cihazı kullanılarak gerçekleştirilebilir. 2. Zaman Altın Nanopartikül Formation in situ Kinetik Çalışmaları Çözüldü <ol><li> Gerekli Kimyasallar: chloroauric asit (. HAuCl 4 3H 2 O) mezo-2 ,3-dimerkaptosüksinik asit (DMSA) ve sodyum bor hidrür &amp; # Edinme160, ve daha fazla arıtılmadan tüm kimyasal kullanımı. Deney için nanopure su (M 18.2 cm) kullanın. </li><li> Tam otomatik, nabız ücretsiz şırınga pompaları çip içerisindeki sıvıları akmaya, yüksek hassasiyet kullanın. Gerekli akış hızını optimize etmek üzere önceki deney için farklı akış hızları ile, çözücü olarak, su ile pompalar edin. </li><li> (I) 4 HAuCl standart solüsyonları hazırlayın. 3H 2 O (10 mmol, 118.2 mg/30 mi) ve NANOpure içinde bir sodyum hidroksit (pH 12), 50 mg (ii) DMSA (20 mmol, 109.2 mg/30 mi) su. </li><li> Otomatik bir pompa kullanılarak 10 ml / st &#39;lik bir sabit akış hızında millifluidic yonga iki ayrı şırınga yoluyla iki çözüm besleyin. </li><li> Çift XYZ yönde hareket erişimi vardır ve çözeltiler çip pompalandı olarak çip üzerine farklı bölgelere XAS veri toplama, bir metal kademesi kullanılarak senkrotron ışın hattına millifluidic çip. </li></ol> &lt;Süreem&gt; in situ analiz prosedürü P-pompa ile millifluidic düzen kullanılarak gösterilmiştir, aynı zamanda, elde tutulan millifluidic cihazı kullanılarak gerçekleştirilebilir. 3. Sürekli Akış Altın kataliz Bu prosedür, bir el millifluidic cihazı kullanılarak gösterilmiştir. <ol><li> Gerekli Kimya: chloroauric asit (. HAuCl 4 3H 2 O), meso-2 ,3-dimerkaptosüksinik asit (DMSA), sodyum borohidrit, 4-nitrofenol, 4-amino fenol elde edilir ve daha fazla saflaştırma olmadan tüm kimyasallar kullanın. Deney için nanopure su (M 18.2 cm) kullanın. </li><li> Katalizör hazırlanması:. HAuCl 4 standart çözeltiler hazırlayın 3H 2 O NANOpure (10 mmol, 118.2 mg/30 mi), DMSA (20 mmol, 109.2 mg/30 mi) ve NaBH4 (10 mmol, 11.34 mg/30 mi) su. </li><li> Iki ayrı şişelere HAuCl 4 ve DMSA çözeltilerin her biri 10 mi almak ve inci akış45 dakika boyunca 12 ml / st &#39;lik muntazam bir akış hızı ile elde tutulan millifluidic cihazı kullanarak çip içinde em. </li><li> Au Au (I) &#39;e düşürmek için, 15 dakika boyunca 12 ml / saat akış hızı ile çip içinde 10 mmol 4 Akış NaBH (0). </li><li> Son olarak, kataliz deneyler yapmadan önce, aynı akış hızında 30 dakika boyunca nanopure su ile çip yıkayın. </li><li> Kataliz reaksiyonu: aşağıda verilen altın katalizörü (yukarıda hazırlanmıştır) içinde 4-aminofenol (4-AP), 4-nitrofenol kimyasal dönüşüm reaksiyonu (redüksiyon) (4-NP) gerçekleştirme millifluidic kanal kaplama. </li><li> 4-nitrophenolate iyon (4-NPI) oluşturmak için 0.65 mol NaBH4 çözeltisi 3.3 ml 4-NP 9 x 10 -5 mol solüsyonu 15 ml karıştırın. </li><li> Katalitik etkinliğini değerlendirmek için 5 ml / sa &#39;lik bir sabit akış hızında çip içinde biriken altın katalizör üzerinden elde edilen solüsyonu geçirir. 250-50 dalga boyu aralığında toplanan ürünlerin UV-Vis spektrumu Analiz0 nm 4-NP dönüşüm onaylayın. </li><li> 4-NPI kalibrasyon eğrisi elde reaksiyonun katalitik aktivitesini tahmin. Kalibrasyon eğrisi farklı standart konsantrasyonlarda 4-NPI, deneysel olarak gözlemlenen emme yoğunluğunu (I) çizilerek elde edilebilir. UV-Vis absorpsiyon eğrileri için (399 nm) pik yükseklikleri emme yoğunluğunu (I) değerleri temsil ve Bira Lambert&#39;in yasaya göre, tepe yüksekliği değerinde herhangi bir değişiklik konsantrasyonu karşılık gelen değişiklik gösterecektir. Bu nedenle, kalibrasyon eğrisinden reaktifin ilk ve son konsantrasyonlarında fark bularak katalitik aktivitesini tahmin ediyoruz. Pik yüksekliği 1 ünite (Şekil 6) ise, örneğin, bu (kalibrasyon grafiği göre)% 90 katalitik bir dönüşüm karşılık gelir. </li></ol>

<ol>
	<li>Song, Y., Hormes, J., Kumar, C. S. S. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microfluidic+Synthesis+of+Nanomaterials.">Microfluidic Synthesis of Nanomaterials.</a> Small. 4 (6), 698-711 (2008).</li><li>Huebner, A., Sharma, S., Srisa-Art, M., Hollfelder, F., Edel, J. B., DeMello, 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=Microdroplets:+a+sea+of+applications.">Microdroplets: a sea of applications.</a> Lab Chip. 8, 1244-1254 (2008).</li><li>Helen, S., Delai, L. C., Rustem, F. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reactions+in+Droplets+in+Microfluidic+Channels.">Reactions in Droplets in Microfluidic Channels.</a> Angew. Chem. Int. Ed. 45, 7336-7356 (2006).</li><li>Marre, S., Jensen, K. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synthesis+of+nanostructures+in+microfluidic+systems.">Synthesis of nanostructures in microfluidic systems.</a> Chem. Soc. Rev. 39, 1183-1202 (2010).</li><li>Theberge, A. B., Courtois, F., Schaerli, Y., Fischlechner, M., Abell, C., Hollfelder, F., Huck, W. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microdroplets+in+microfluidics:+an+evolving+platform+for+discoveries+in+chemistry+and+biology.">Microdroplets in microfluidics: an evolving platform for discoveries in chemistry and biology.</a> Angew. Chem. Int. Ed. 49 (34), 5846-5868 (2010).</li><li>Nicolas, L., Flavie, S., Pierre, G., Pascal, P., Annie, C., Bertrand, P., Cindy, H., Patrick, M., Samuel, M., Thomas, D., Cyril, A., Pascale, S., Laurent, P., Christopher, G., Emmanuel, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Some+recent+advances+in+the+design+and+the+use+of+miniaturized+droplet-based+continuous+process:+Applications+in+chemistry+and+high-pressure+microflows.">Some recent advances in the design and the use of miniaturized droplet-based continuous process: Applications in chemistry and high-pressure microflows.</a> Lab Chip. 11, 779 (2011).</li><li>Biswas, S., Miller, J. T., Li, Y., Nandakumar, K., Kumar, C. S. S. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Developing+Millifluidic+Platform+for+Synthesis+of+Ultra-small+Nanoclusters+(UNCs):+Ultra-small+Copper+Nanoclusters+(UCNCs)+as+a+Case+Study.">Developing Millifluidic Platform for Synthesis of Ultra-small Nanoclusters (UNCs): Ultra-small Copper Nanoclusters (UCNCs) as a Case Study.</a> Small. 8 (5), 688-698 (2012).</li><li>Li, Y., Sanampudi, A., Reddy, V. R., Biswas, S., Nandakumar, K., Yamane, D. G., Goettert, J. S., Kumar, C. S. S. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Size+Evolution+of+Gold+Nanoparticles+in+a+Millifluidic+Reactor.">Size Evolution of Gold Nanoparticles in a Millifluidic Reactor.</a> Phys. Chem. Phys. 13 (1), 177-182 (2012).</li><li>Li, Y., Yamane, D. G., Li, S., Biswas, S., Reddy, R., Goettert, J. S., Nandakumar, K., Kumar, C. S. S. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Geometric+Optimization+of+Liquid-Liquid+Slug+Flow+in+a+Flow-focusing+Millifluidic+Device+for+Synthesis+of+Nanomaterials.">Geometric Optimization of Liquid-Liquid Slug Flow in a Flow-focusing Millifluidic Device for Synthesis of Nanomaterials.</a> Chem. Eng. J. 217, 447-459 (2013).</li><li>Zinoveva, S., De Silva, R., Louis, R. D., Datta, P., Kumar, C. S. S. R., Goettert, J., Hormes, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+wet+chemical+synthesis+of+Co+nanoparticles+in+a+microreactor+system:+A+time-resolved+investigation+by+X-ray+absorption+spectroscopy.">The wet chemical synthesis of Co nanoparticles in a microreactor system: A time-resolved investigation by X-ray absorption spectroscopy.</a> Nucl. Instrum. Methods Phys. Res. A. 582, 239-241 (2007).</li><li>Krishna, K. S., Navin, C. V., Biswas, S., Singh, V., Ham, K., Bovenkamp, G. L., Theegala, C. S., Miller, J. T., Spivey, J., Kumar, C. S. S. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Millifluidics+for+Time-resolved+Mapping+of+the+Growth+of+Gold+Nanostructures.">Millifluidics for Time-resolved Mapping of the Growth of Gold Nanostructures.</a> J. Am. Chem. Soc. 135 (14), 5450-5456 (2013).</li><li>Kumar, C. S. S. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Microfluidic Devices in nanotechnology-Fundamental Concepts. , (2010).</li><li>Kumar, C. S. S. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Microfluidic Devices in nanotechnology-Fundamental Concepts. , (2010).</li><li>Meille, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Review+on+Methods+to+Deposit+Catalysts+on+Structured+Surfaces.">Review on Methods to Deposit Catalysts on Structured Surfaces.</a> Appl. Catal. A Gen. 315, 1-17 (2006).</li><li>Shin, W. C., McDonald, J. A., Zhao, S., Besser, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Etching+Characteristics+of+a+Micromachined+Chemical+Reactor+Using+Inductively+Coupled+Plasma.">Etching Characteristics of a Micromachined Chemical Reactor Using Inductively Coupled Plasma.</a> , p357 (2002).</li><li>Abahmane, L., K&#246;hler, J. M., Gro&#223;, G. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gold-nanoparticle-catalyzed+synthesis+of+propargylamines:+the+traditional+A3-multicomponent+reaction+performed+as+a+two-step+flow+process.">Gold-nanoparticle-catalyzed synthesis of propargylamines: the traditional A3-multicomponent reaction performed as a two-step flow process.</a> Chem. Eur. J. 17, 3005-3010 (2011).</li><li>Abahmane, L., Knauer, A., Ritter, U., K&#246;hler, J. M., Gro&#223;, G. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Heterogeneous+Catalyzed+Pyridine+Synthesis+using+Montmorillionite+and+Nanoparticle-Impregnated+Alumina+in+a+Continuous+Micro+Flow+System.">Heterogeneous Catalyzed Pyridine Synthesis using Montmorillionite and Nanoparticle-Impregnated Alumina in a Continuous Micro Flow System.</a> Chem. Eng. Technol. 32, 1799-1805 (2009).</li><li>Abahmane, L., Knauer, A., K&#246;hler, J. M., Gro&#223;, G. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synthesis+of+polypyridine+derivatives+using+alumina+supported+gold+nanoparticles+under+micro+continuous+flow+conditions.">Synthesis of polypyridine derivatives using alumina supported gold nanoparticles under micro continuous flow conditions.</a> Chem. Eng. J. 167, 519-526 (2011).</li><li>Negishi, Y., Tsukuda, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=One-Pot+Preparation+of+Subnanometer-Sized+Gold+Clusters+via+Reduction+and+Stabilization+by+meso-2,3-Dimercaptosuccinic+Acid.">One-Pot Preparation of Subnanometer-Sized Gold Clusters via Reduction and Stabilization by meso-2,3-Dimercaptosuccinic Acid.</a> J. Am. Chem. Soc. 125, 4046-4047 (2003).</li><li>Abou-Hassan, A., Sandre, O., Cabuil, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microfluidics+in+Inorganic+Chemistry.">Microfluidics in Inorganic Chemistry.</a> Angew. Chem. Int. Ed. 49, 6268-6286 (2010).</li><li>Jiang, D., Walter, M., Dai, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gold+Sulfide+Nanoclusters:+A+Unique+Core-In-Cage+Structure.">Gold Sulfide Nanoclusters: A Unique Core-In-Cage Structure.</a> Chem. Eur. J. 16, 4999-5003 (2010).</li><li>Kuroda, K., Ishida, T., Haruta, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reduction+of+4-nitrophenol+to+4-aminophenol+over+Au+nanoparticles+deposited+on+PMMA.">Reduction of 4-nitrophenol to 4-aminophenol over Au nanoparticles deposited on PMMA.</a> J. Mol. Catal. A Chem. 298, 7-11 (2009).</li><li>Navin, C. V., Krishna, K. S., Theegala, C. S., Kumar, C. S. S. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lab-on-a-chip+devices+for+gold+nanoparticle+synthesis+and+their+role+as+a+catalyst+support+for+continuous+flow+catalysis.">Lab-on-a-chip devices for gold nanoparticle synthesis and their role as a catalyst support for continuous flow catalysis.</a> Nanotech. Rev. , (2013).</li><li>Shahbazali, E., Hessel, V., No&#235;l, T., Wang, Q. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Metallic+nanoparticles+made+in+flow+and+their+catalytic+applications+in+organic+synthesis.">Metallic nanoparticles made in flow and their catalytic applications in organic synthesis.</a> Nanotech. Rev. , (2013).</li></ol>

CSSR Kaya hariç tüm yazarlar hiçbir rakip mali çıkarlarını olmadığını beyan ederim. C. SSR Kumar şirketin Millifluidica LLC kurucusudur.

-O&#39;-metilpolietilen glikol (MW = 5,000) [MPEG] - UCNCs polimerik kapatma maddesi O-[(3-Mercaptopropionylamino) etil 2] mevcudiyetinde sodyum borohidrit ile bakır nitrat indirgeme reaksiyonu ile oluşturulmuştur. Reaksiyon, 6.8 ml / saat, 14,3 ml / saat, 32.7 ml / st ve oluşan UCNCs on akış hızlarının etkisini incelemek için 51.4 ml / saat olarak farklı akış-oranlarda millifluidic çip reaktör içinde gerçekleştirilmiştir. Yukarıda akış oranları için, ilgili kalış süreleri 47.49, 24.44, 16.56 ...

Kimyasal sentez için lab-on-a-chip (LOC) cihazları artmış kütle ve ısı transferi, üstün reaksiyon kontrolü, yüksek verim ve daha güvenli bir çalışma ortamı 1. açısından önemli bir avantaj göstermiştir. Bu cihazlar geniş yonga tabanlı akışkansal ve nonchip bazlı akışkan cihazlara ayrılabilir. Çip tabanlı akışkansal arasında, Mikroakiskan iyi incelenmiş ve konu literatürde 2-5 iyi kaplı. Nonchip tabanlı LOC sistemleri tubular reaktörler 6 kullanın. Geleneksel olarak, mikroakışkan sistemleri tam kontrol ve geometrik milimetre altı ölçeğe kısıtlı sıvıların manipülasyonu için kullanılır. Son zamanlarda (genişlik veya derinlik ya da kanalların iki ya da boyutu en az bir milimetre) 7-9 milimetre ölçeğinde kanallarında sıvıların manipülasyonu için kullanılabilecek çipli millifluidics, kavramını var. Ayrıca, millifluidic cips WHI imal etmek nispeten kolaydırle akış oranları ve reaktiflerin manipülasyon üzerinde benzer bir kontrol sunuyor. Bu yongalar, aynı zamanda daha dar bir boyut dağılımına sahip nanopartiküller kontrollü sentezinin ölçek büyütme için olanak sağlar, ve böylece, daha az kalma süreleri oluşturma, daha yüksek akış hızlarında çalıştırılabilir. Örnek olarak, biz son zamanlarda ultra-küçük bakır nanoklastırlaar sentezini gösterdi ve yerinde X-ışını soğurma spektroskopisi kullanarak yanı sıra TEM onları karakterize var. Bakır nanoklastırlar 7 istikrarlı koloitlerin oluşumu için çok etkili iki dişli PEG&#39;lenmiş stabilize edici madde, MPEG, kullanımı ile kombine millifluidic kanal içinde küçük kalma süreleri elde etmek için yeteneği. Kimyasal ve nanomalzemelerin sentezine ek olarak, millifluidics nedeniyle prob alanında yüksek satış hacmi ve konsantrasyonu, daha genel ve verimli bir zaman çözümlü bir kinetik çalışmalar için ve aynı zamanda achie olan sentetik bir platforma, sunabilirakışkan sistemleri 7,10 daha gürültü oranı daha iyi sinyal ves. Biz 5 msn 11 gibi küçük bir zaman çözünürlüğü ile in situ XAS kullanılarak çözeltiden altın Nano büyümesinin zaman çözüldü analizi için bir örnek olarak millifluidic çip kullanımını göstermektedir. Ayrıca, kataliz uygulamaları için bugüne kadar geliştirilen mikro reaktörlerin çoğunluğu silikon 12,13 dayanmaktadır. Oluşturulan küçük birimlere ek olarak kendi pahalı üretim büyük ölçekli üretim için onları uygun hale getirir. Nanocatalysts ile kanal kaplanması için iki genel yöntem - kimyasal ve fiziksel, genellikle silikon kaplama işlemleri olarak adlandırılan, rağbet 14,15 şu anda. Mikro pahalı imalat ek olarak, kanalların tıkanması mikro reaktör kataliz büyük ölçekli üretim için uygun olabilir hale getirir. Microreactors mikro sürekli akış geçiş işlemleri earli heterojen kataliz için kullanılmış olsa da16-18 er, boyut kontrol yeteneği ve sürekli akış kanalları içinde gömülü altın nano yapılı katalizörler morfolojisi önce keşfedilmeyi değildi. Biz son zamanlarda, Au katalizörü ile millifluidic kanalları kaplanması için bir teknoloji geliştirdik nano morfolojisi ve boyutları (Şekil 5) 11 kontrollü olan, endüstriyel önemli kimyasal reaksiyonlar katalizini yürütülmesi için. Bir örnek olarak millifluidic kanalları içinde kaplanmış altın nano yapılı ile katalize 4-aminofenol, 4-nitrofenol dönüşüm göstermiştir. Tek bir millifluidic reaktör çip 50-60 ml / saat, 7 yüksek verimlilik ve kimyasalların kontrollü sentezinin akış oranlarını üretebilir olduğu göz önüne alındığında, ya sürekli akış işletim veya paralel işleme ile mümkündür. Millifluidics yukarıda tarif kaç örnekle, teklif olanakları yararlanmak için, biz de göstermek kullanıcı dostu birtaşınabilir ve var millifluidic cihaz gibi millifluidic cips, manifoldlar, akış kontrol, pompa ve elektrik bağlantıları gibi tüm gerekli bileşenleri entegre. Böyle bir millifluidic cihazı, Şekil 7&#39;de gösterildiği gibi, hemen işletme Millifluidica LLC (edinilebilir <a href="http://www.millifluidica.com" target="_blank">www.millifluidica.com</a> ). Makale ayrıca nanomalzemelerin, tepkime mekanizmaları ve sürekli akış kataliz zaman çözümlü analizi kontrol sentezi için, aşağıda tarif edildiği gibi, elde tutulan cihazı kullanılarak millifluidic protokolleri sağlar.

<table border="1">
	<tbody>
		<tr>
			<td>Copper (II) nitrate hydrate</td>
			<td>Sigma-Aldrich</td>
			<td>13778-31-9</td>
			<td>99.999% pure</td>
		</tr>
		<tr>
			<td>O-[2-(3-mercaptopropionylamino)ethyl]-O&#8242;-methylpolyethylene glycol</td>
			<td>Sigma-Aldrich</td>
			<td>401916-61-8&#160;</td>
			<td>MW=5,000</td>
		</tr>
		<tr>
			<td>HAuCl4.3H2O (Chloroauric acid)</td>
			<td>Sigma-Aldrich</td>
			<td>27988-77-8&#160;</td>
			<td>99.999% pure</td>
		</tr>
		<tr>
			<td>meso-2,3-dimercaptosuccinic acid (DMSA)</td>
			<td>Sigma-Aldrich</td>
			<td>304-55-2</td>
			<td>~98% pure</td>
		</tr>
		<tr>
			<td>4-Nitrophenol</td>
			<td>Sigma-Aldrich</td>
			<td>100-02-7&#160;</td>
			<td>spectrophotometric grade</td>
		</tr>
		<tr>
			<td>4-Aminophenol</td>
			<td>Sigma-Aldrich</td>
			<td>123-30-8&#160;</td>
			<td>&#62;99% pure (HPLC grade)</td>
		</tr>
		<tr>
			<td>Sodium borohydride</td>
			<td>Sigma-Aldrich</td>
			<td>16940-66-2&#160;</td>
			<td>98% pure</td>
		</tr>
		<tr>
			<td>Sodium hydroxide pellets</td>
			<td>Sigma-Aldrich</td>
			<td>1310-73-2&#160;</td>
			<td>99.99% pure</td>
		</tr>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td>[header]</td>
		</tr>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td>EQUIPMENT</td>
		</tr>
		<tr>
			<td>Millifluidic Chips</td>
			<td>Microplumbers Microsciences LLC</td>
			<td>SDC-01</td>
			<td>Made from polyester terephthalate polymer</td>
		</tr>
		<tr>
			<td>Pressure Pump</td>
			<td>Mitos P-Pump, Dolomite</td>
			<td>3200016</td>
			<td></td>
		</tr>
		<tr>
			<td>Automated Syringe Pump</td>
			<td>Cetoni Automation and Microsystems, GmbH</td>
			<td></td>
			<td>Syringe pump neMESYS</td>
		</tr>
		<tr>
			<td>UV-3600 UV-VIS-NIR Spectrophotometer</td>
			<td>Shimadzu</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Hand-held Millifluidic Device</td>
			<td>Millifluidica</td>
			<td>SCMD-1008</td>
			<td>Figure 7</td>
		</tr>
	</tbody>
</table>

millifluidics for chemical synthesis and time-resolved mechanistic studies

Kimyasal sentez ve zaman çözümlü bir mekanik çalışmalar için millifluidic cihazlarını kullanan işlemler üç örnek alınarak açıklanmıştır. İlk olarak, çok küçük bakır nanoklastırlaar sentezi tarif edilmektedir. İkinci örnek yerinde X-ışını soğurma spektroskopi kullanarak altın nanoparçacık oluşumunu analiz kimyasal reaksiyonların zaman çözülmesi kinetik soruşturma için kendi yarar sağlar. Nihai örneğin nano yapılı katalizör ile kaplanmış kanal iç millifluidic reaksiyonlar sürekli akış kataliz gösterir.

Iyi dağıtılmış ve dar bir boyut dağılımı ile muntazam boyutlu bakır nanoklastırlar millifluidic yonga setup (Şekil 1a) kullanılarak elde edildi. Sentezi için kullanılan farklı akış hızları kümelerin boyutu üzerinde önemli bir etkiye sahip değildi. Bununla birlikte, akış hızındaki artış ile, boyut dağılımının daralması gözlenebilir bir gelişme yoktur. En iyi dar bir boyut dağılımına sahip UCNCs 32,7 ml / saatlik bir akış hızı ile elde edildi. 32,7 ml / saat akış hızı ile ...

Watch this Scientific Journal Video about Millifluidics for Chemical Synthesis and Time-resolved Mechanistic Studies at JoVE.com

Millifluidics for Chemical Synthesis and Time-resolved Mechanistic Studies

Millifluidic Nanomalzemelere aygıtları, tepkime mekanizmaları ve sürekli akış kataliz zaman çözümlü bir analiz olarak kontrol edilen sentez için kullanılmaktadır.

Kimyasal Sentez ve Zaman-çözülmesi Mekanistiksel Çalışmaları Millifluidics

Procedures utilizing millifluidic devices for chemical synthesis and time-resolved mechanistic studies are described by taking three examples. In the ...

millifluidics-for-chemical-synthesis-time-resolved-mechanistic

Research

Education

JoVE Journal

JoVE Core

Physics

Bioengineering

Unit 1

Work and Kinetic Energy

SCIENTISTS IN ACTION

11.1K Görüntüleme.  Louisiana State University.  Millifluidic Nanomalzemelere aygıtları, tepkime mekanizmaları ve sürekli akış kataliz zaman çözümlü bir analiz olarak kontrol edilen sentez için kullanılmaktadır. 

Video: Millifluidics for Chemical Synthesis and Time-resolved Mechanistic Studies

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.

Kombinatorik Sentezi ve Polimer Film ve Nanoparçacık Kütüphaneler gelen Yüksek throughput Protein Yayın

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

Biyomühendislik

High-throughput Synthesis of Carbohydrates and Functionalization of Polyanhydride Nanoparticles

Transdisciplinary approaches involving areas such as material design, nanotechnology, chemistry, and immunology have to be utilized to rationally design efficacious vaccines carriers. Nanoparticle-based platforms can prolong the persistence of vaccine antigens, which could improve vaccine immunogenicity1. Several biodegradable polymers have been studied as vaccine delivery vehicles1; in particular, polyanhydride particles have demonstrated the ability to provide sustained release of stable protein antigens and to activate antigen presenting cells and modulate immune responses2-12.
The molecular design of these vaccine carriers needs to integrate the rational selection of polymer properties as well as the incorporation of appropriate targeting agents. High throughput automated fabrication of targeting ligands and functionalized particles is a powerful tool that will enhance the ability to study a wide range of properties and will lead to the design of reproducible vaccine delivery devices.
The addition of targeting ligands capable of being recognized by specific receptors on immune cells has been shown to modulate and tailor immune responses10,11,13 C-type lectin receptors (CLRs) are pattern recognition receptors (PRRs) that recognize carbohydrates present on the surface of pathogens. The stimulation of immune cells via CLRs allows for enhanced internalization of antigen and subsequent presentation for further T cell activation14,15. Therefore, carbohydrate molecules play an important role in the study of immune responses; however, the use of these biomolecules often suffers from the lack of availability of structurally well-defined and pure carbohydrates. An automation platform based on iterative solution-phase reactions can enable rapid and controlled synthesis of these synthetically challenging molecules using significantly lower building block quantities than traditional solid-phase methods16,17.
Herein we report a protocol for the automated solution-phase synthesis of oligosaccharides such as mannose-based targeting ligands with fluorous solid-phase extraction for intermediate purification. After development of automated methods to make the carbohydrate-based targeting agent, we describe methods for their attachment on the surface of polyanhydride nanoparticles employing an automated robotic set up operated by LabVIEW as previously described10. Surface functionalization with carbohydrates has shown efficacy in targeting CLRs10,11 and increasing the throughput of the fabrication method to unearth the complexities associated with a multi-parametric system will be of great value (Figure 1a).

In this article, a high throughput method is presented for the synthesis of oligosaccharides and their attachment to the surface of polyanhydride nanoparticles for further use in targeting specific receptors on antigen presenting cells.

Polianhidrid Nanopartiküller Yüksek throughput Karbonhidrat sentezi ve işlevsel

Transdisciplinary approaches involving areas such as material design, nanotechnology, chemistry, and immunology have to be utilized to rationally design ...

Microfabrication of Nanoporous Gold Patterns for Cell-material Interaction Studies

Nanostructured materials with feature sizes in tens of nanometers have enhanced the performance of several technologies, including fuel cells, biosensors, biomedical device coatings, and drug delivery tools. Nanoporous gold (np-Au), produced by a nano-scale self-assembly process, is a relatively new material that exhibits large effective surface area, high electrical conductivity, and catalytic activity. These properties have made np-Au an attractive material to scientific community. Most studies on np-Au employ macro-scale specimens and focus on fundamental science of the material and its catalytic and sensor applications. The macro-scale specimens limit np-Au's potential in miniaturized systems, including biomedical devices. In order to address these issues, we initially describe two different methods to micropattern np-Au thin films on rigid substrates. The first method employs manually-produced stencil masks for creating millimeter-scale np-Au patterns, while the second method uses lift-off photolithography to pattern sub-millimeter-scale patterns. As the np-Au thin films are obtained by sputter-deposition process, they are compatible with conventional microfabrication techniques, thereby amenable to facile integration into microsystems. These systems include electrically-addressable biosensor platforms that benefit from high effective surface area, electrical conductivity, and gold-thiol-based surface bioconjugation. We describe cell culture, immunostaining, and image processing techniques to quantify np-Au's interaction with mammalian cells, which is an important performance parameter for some biosensors. We expect that the techniques illustrated here will assist the integration of np-Au in platforms at various length-scales and in numerous applications, including biosensors, energy storage systems, and catalysts.

We report on techniques to micropattern nanoporous gold thin films via stencil printing and photolithography, as well as methods to culture cells on the microfabricated patterns. In addition, we describe image analysis methods to characterize morphology of the material and the cultured cells using scanning electron and fluorescence microscopy techniques.

Hücre-malzeme Etkileşim Araştırmalar Nanogözenekli Altın Patterns mikroimalat

Nanostructured materials with feature sizes in tens of nanometers have enhanced the performance of several technologies, including fuel cells, biosensors, ...

Synthesis of an Intein-mediated Artificial Protein Hydrogel

We present the synthesis of a highly stable protein hydrogel mediated by a split-intein-catalyzed protein trans-splicing reaction. The building blocks of this hydrogel are two protein block-copolymers each containing a subunit of a trimeric protein that serves as a crosslinker and one half of a split intein. A highly hydrophilic random coil is inserted into one of the block-copolymers for water retention. Mixing of the two protein block copolymers triggers an intein trans-splicing reaction, yielding a polypeptide unit with crosslinkers at either end that rapidly self-assembles into a hydrogel. This hydrogel is very stable under both acidic and basic conditions, at temperatures up to 50 &#176;C, and in organic solvents. The hydrogel rapidly reforms after shear-induced rupture. Incorporation of a &#34;docking station peptide&#34; into the hydrogel building block enables convenient incorporation of &#34;docking protein&#34;-tagged target proteins. The hydrogel is compatible with tissue culture growth media, supports the diffusion of 20 kDa molecules, and enables the immobilization of bioactive globular proteins. The application of the intein-mediated protein hydrogel as an organic-solvent-compatible biocatalyst was demonstrated by encapsulating the horseradish peroxidase enzyme and corroborating its activity.

We present the synthesis of a split-intein-mediated protein hydrogel. The building blocks of this hydrogel are two protein copolymers each containing a subunit of a trimeric protein that serves as a crosslinker and one half of a split intein. Mixing of the two protein copolymers triggers an intein trans-splicing reaction, yielding a polypeptide unit that self-assembles into a hydrogel. This hydrogel is highly pH- and temperature-stable, compatible with organic solvents, and easily incorporates functional globular proteins.

Bir Intein aracılı yapay protein Hidrojel sentezi

We present the synthesis of a highly stable protein hydrogel mediated by a split-intein-catalyzed protein trans-splicing reaction. The building blocks of ...

Synthesis of Keratin-based Nanofiber for Biomedical Engineering

Electrospinning, due to its versatility and potential for applications in various fields, is being frequently used to fabricate nanofibers. Production of these porous nanofibers is of great interest due to their unique physiochemical properties. Here we elaborate on the fabrication of keratin containing poly (&#949;-caprolactone) (PCL) nanofibers (i.e., PCL/keratin composite fiber). Water soluble keratin was first extracted from human hair and mixed with PCL in different ratios. The blended solution of PCL/keratin was transformed into nanofibrous membranes using a laboratory designed electrospinning set up. Fiber morphology and mechanical properties of the obtained nanofiber were observed and measured using scanning electron microscopy and tensile tester. Furthermore, degradability and chemical properties of the nanofiber were studied by FTIR. SEM images showed uniform surface morphology for PCL/keratin fibers of different compositions. These PCL/keratin fibers also showed excellent mechanical properties such as Young&#39;s modulus and failure point. Fibroblast cells were able to attach and proliferate thus proving good cell viability. Based on the characteristics discussed above, we can strongly argue that the blended nanofibers of natural and synthetic polymers can represent an excellent development of composite materials that can be used for different biomedical applications.

Electrospun nanofibers have a high surface area to weight ratio, excellent mechanical integrity, and support cell growth and proliferation. These nanofibers have a wide range of biomedical applications. Here we fabricate keratin/ PCL nanofibers, using the electrospinning technique, and characterize the fibers for possible applications in tissue engineering.

Biyomedikal Mühendisliği için keratin bazlı nanofiber sentezi

Electrospinning, due to its versatility and potential for applications in various fields, is being frequently used to fabricate nanofibers. Production of ...

The Synthesis of RGD-functionalized Hydrogels as a Tool for Therapeutic Applications

The use of polymers as biomaterials has provided significant advantages in therapeutic applications. In particular, the possibility to modify and functionalize polymer chains with compounds that are able to improve biocompatibility, mechanical properties, or cell viability allows the design of novel materials to meet new challenges in the biomedical field. With the polymer functionalization strategies, click chemistry is a powerful tool to improve cell-compatibility and drug delivery properties of polymeric devices. Similarly, the fundamental need of biomedicine to use sterile tools to avoid potential adverse-side effects, such as toxicity or contamination of the biological environment, gives rise to increasing interest in the microwave-assisted strategy.
The combination of click chemistry and the microwave-assisted method is suitable to produce biocompatible hydrogels with desired functionalities and improved performances in biomedical applications. This work aims to synthesize RGD-functionalized hydrogels. RGD (arginylglycylaspartic acid) is a tripeptide that can mimic cell adhesion proteins and bind to cell-surface receptors, creating a hospitable microenvironment for cells within the 3D polymeric network of the hydrogels. RGD functionalization occurs through Huisgen 1,3-dipolar cycloaddition. Some PAA carboxyl groups are modified with an alkyne moiety, whereas RGD is functionalized with azido acid as the terminal residue of the peptide sequence. Finally, both products are used in a copper catalyzed click reaction to permanently link the peptide to PAA. This modified polymer is used with carbomer, agarose and polyethylene glycol (PEG) to synthesize a hydrogel matrix. The 3D structure is formed due to an esterification reaction involving carboxyl groups from PAA and carbomer and hydroxyl groups from agarose and PEG through microwave-assisted polycondensation. The efficiency of the gelation mechanism ensures a high degree of RGD functionalization. In addition, the procedure to load therapeutic compounds or biological tools within this functionalized network is very simple and reproducible.

We present a protocol for the synthesis of RGD-functionalized hydrogels as devices for cell and drug delivery. The procedure involves copper catalyzed alkyne-azide cycloaddition (CuAAC) between alkyne-modified polyacrylic acid (PAA) and a RGD-azide derivative. The hydrogels are formed using microwave-assisted polycondensation and their physicochemical properties are investigated.

Tedavi Uygulamaları için bir alet olarak RGD-fonksiyonelleştirilmiş Hidrojeller Sentezi

The use of polymers as biomaterials has provided significant advantages in therapeutic applications. In particular, the possibility to modify and ...

Polydimethylsiloxane-polycarbonate Microfluidic Devices for Cell Migration Studies Under Perpendicular Chemical and Oxygen Gradients

This paper reports a microfluidic device made of polydimethylsiloxane (PDMS) with an embedded polycarbonate (PC) thin film to study cell migration under combinations of chemical and oxygen gradients. Both chemical and oxygen gradients can greatly affect cell migration in vivo; however, due to technical limitations, very little research has been performed to investigate their effects in vitro. The device developed in this research takes advantage of a series of serpentine-shaped channels to generate the desired chemical gradients and exploits a spatially confined chemical reaction method for oxygen gradient generation. The directions of the chemical and oxygen gradients are perpendicular to each other to enable straightforward migration result interpretation. In order to efficiently generate the oxygen gradients with minimal chemical consumption, the embedded PC thin film is utilized as a gas diffusion barrier. The developed microfluidic device can be actuated by syringe pumps and placed into a conventional cell incubator during cell migration experiments to allow for setup simplification and optimized cell culture conditions. In cell experiments, we used the device to study migrations of adenocarcinomic human alveolar basal epithelial cells, A549, under combinations of chemokine (stromal cell-derived factor, SDF-1&#945;) and oxygen gradients. The experimental results show that the device can stably generate perpendicular chemokine and oxygen gradients and is compatible with cells. The migration study results indicate that oxygen gradients may play an essential role in guiding cell migration, and cellular behavior under combinations of gradients cannot be predicted from those under single gradients. The device provides a powerful and practical tool for researchers to study interactions between chemical and oxygen gradients in cell culture, which can promote better cell migration studies in more in vivo-like microenvironments.

The control of chemical and oxygen gradients is essential for cell cultures. This paper reports a polydimethylsiloxane-polycarbonate (PDMS-PC) microfluidic device capable of reliably generating combinations of chemical and oxygen gradients for cell migration studies, which can be practically utilized in biological labs without sophisticated instrumentation.

Hücre Göç Çalışmaları altında Dik Kimya ve Oksijen Gradyanların için polidimetilsiloksan-polikarbonat mikroakışkan Cihazlar

This paper reports a microfluidic device made of polydimethylsiloxane (PDMS) with an embedded polycarbonate (PC) thin film to study cell migration under ...

Synthesis of Hydrogels with Antifouling Properties As Membranes for Water Purification

Hydrogels have been widely utilized to enhance the surface hydrophilicity of membranes for water purification, increasing the antifouling properties and thus achieving stable water permeability through membranes over time. Here, we report a facile method to prepare hydrogels based on zwitterions for membrane applications. Freestanding films can be prepared from sulfobetaine methacrylate (SBMA) with a crosslinker of poly(ethylene glycol) diacrylate (PEGDA) via photopolymerization. The hydrogels can also be prepared by impregnation into hydrophobic porous supports to enhance the mechanical strength. These films can be characterized by attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) to determine the degree of conversion of the (meth)acrylate groups, using goniometers for hydrophilicity and differential scanning calorimetry (DSC) for polymer chain dynamics. We also report protocols to determine the water permeability in dead-end filtration systems and the effect of foulants (bovine serum albumin, BSA) on membrane performance.

This paper reports practical methods to prepare hydrogels in freestanding films and impregnated membranes and to characterize their physical properties, including water transport properties.

Su Arıtma Membranlar olarak Zehirli Özelliklere Sahip Hidrojeller Sentezi

Hydrogels have been widely utilized to enhance the surface hydrophilicity of membranes for water purification, increasing the antifouling properties and ...

Ammonia Synthesis at Low Pressure

Ammonia can be synthesized at low pressure by the use of an ammonia selective absorbent. The process can be driven with wind energy, available locally in areas requiring ammonia for synthetic fertilizer. Such wind energy is often called &#34;stranded,&#34; because it is only available far from population centers where it can be directly used.
In the proposed low pressure process, nitrogen is made from air using pressure swing absorption, and hydrogen is produced by electrolysis of water. While these gases can react at approximately 400 &#176;C in the presence of a promoted conventional catalyst, the conversion is often limited by the reverse reaction, which makes this reaction only feasible at high pressures. This limitation can be removed by absorption on an ammine-like calcium or magnesium chloride. Such alkaline metal halides can effectively remove ammonia, thus suppressing the equilibrium constraints of the reaction. In the proposed absorption-enhanced ammonia synthesis process, the rate of reaction may then be controlled not by the chemical kinetics nor the absorption rates, but by the rate of the recycle of unreacted gases. The results compare favorably with ammonia made from a conventional small scale Haber-Bosch process.

Ammonia can be synthesized at low pressure by using a conventional catalyst and an ammonia selective absorbent.

Düşük basınçta amonyak sentezi

Ammonia can be synthesized at low pressure by the use of an ammonia selective absorbent. The process can be driven with wind energy, available locally in ...

Synthesis of Functionalized 10-nm Polymer-coated Gold Particles for Endothelium Targeting and Drug Delivery

Gold nanoparticles (AuNPs) have been used extensively in medical research due to their size, biocompatibility, and modifiable surface. Specific targeting and drug delivery are some of the applications of these AuNPs, but endothelial extracellular matrices&#39; defensive properties hamper particle uptake. To address this issue, we describe a synthesis method for ultrasmall gold nanoparticles to improve vascular delivery, with customizable functional groups and polymer lengths for further adjustments. The protocol yields 2.5 nm AuNPs that are capped with tetrakis(hydroxymethyl)phosphonium chloride (THPC). The replacement of THPC with hetero-functional polyethylene glycol (PEG) on the surface of the AuNP increases the hydrodynamic radius to 10.5 nm while providing various functional groups on the surface. The last part of the protocol includes an optional addition of a fluorophore to allow the AuNPs to be visualized under fluorescence to track nanoparticle uptake. Dialysis and lyophilization were used to purify and isolate the AuNPs. These fluorescent nanoparticles can be visualized in both in vitro and in vivo experiments due to the biocompatible PEG coating and fluorescent probes. Additionally, the size range of these nanoparticles render them an ideal candidate for probing the glycocalyx without disrupting normal vasculature function, which may lead to improved delivery and therapeutics.

We describe a method of synthesizing biocompatible 10-nm gold nanoparticles, functionalized by coating poly-ethylene glycol onto the surface. These particles can be used in vitro and in vivo for delivering therapeutics to nanoscale cellular and extracellular spaces that are difficult to access with conventional nanoparticle sizes.

Endotel hedefleme için Functionalized 10-nm polimer kaplı altın parçacıkları ve ilaç dağıtım sentezi

Gold nanoparticles (AuNPs) have been used extensively in medical research due to their size, biocompatibility, and modifiable surface. Specific targeting ...