KG RA Welch Vakfı hibe P-1760 tarafından desteklenen, Matematik &amp; (KG) Fen Eğitimi TCU Andrews Enstitüsü, TCU Araştırma ve Yaratıcılık Faaliyet Hibe (KG) ve (EHS için) TCU SERC Grant.

Biyotin-Fc-sistein 1. N- (1) <ol><li> Katı faz yöntemleri 1 reçineye bağlı üretmek. <ol><li> Bir fritli şırınga içine biyotin yüklenmiş reçine (250 mg, 0.145 mmol), koyun ve dimetilformamid (5 mi) içine çekilmesi ve 20 dakika süre ile bir laboratuar karıştırıcısı üzerinde şırınga çalkalayarak, reçineyi kabartmak. Çözüm sınırdışı ve bir kez daha şişme dimetilformamid tekrarlayın. </li><li> Çalkalama 10-15 dakika süre ile bir şırınga dimetilformamid içinde% 20 piperidin içinde 6/4 ml ilave etmek suretiyle Fmoc koruyucu grubu kaldırmak. Piperidin başka 4-6 ml korumanın kaldırılması işlemi tekrarlayın. ~, 3x diklorometan 5 ml her biri metanol (1: 1), 3x metanol: diklorometan (1: 1) 3x dimetilformamid sekansı 3x dimetilformamid reçinenin yıkayın. Isıtma üzerine mavi varlığı başarılı korumasının kaldırılması onaylamak için boncuk küçük bir örnekleme (~ 10) üzerinde bir ninhidrin testi (+) yapın. </li><li> 1&#39;-Fmoc-amino-ferrosen-1-karboksilik asit ihtiva eden bir çözelti karıştırın(203,3 mg, 0,4350 mmol), 1-hidroksibenzotriazol hidrat (58.8 mg, 0.413 mmol), diisopropil karbodiimid (0,0673 mi, 0.435 mmol), diizopropil etil amin (0,0757 mi, 0.435 mmol) ve 4: diklorometan 1 karışımı Dimetilformamit içine yerleştirilir. Sırlı şırınganın içine bu çizin ve 6 saat süreyle bir laboratuar çalkalayıcı üzerinde yavaşça çalkalayın. Daha sonra şırınga çözüm çıkarmak ve daha önce tarif edildiği gibi yıkama yapılır. </li><li> Kaplin doğrulamak için, yukarıda anlatıldığı gibi (-) ninhidrin testi gerçekleştirir. Ninhidrin testi hala parçasını içeren demir eki elde edilen boncuk portakal rengi rağmen kaplin teyit de yararlı olabilir. </li><li> Sonra dimetilformamid içinde% 20 piperidin ile eklenmesi ile Fmoc grubunun çıkarılması ve yukarıda tarif edildiği gibi yıkanmıştır. Ninhidrin testi (+) Fmoc kaldırma teyit etmek için kullanılmalıdır. </li><li> (0,0673 ml Fmoc-Cys (Trt) oluşan bir çözelti -OH (254,8 mg, 0,4350 mmol), 1-hidroksibenzotriazol hidrat (58.8 mg, 0,4125 mmol), diisopropil karbodiimid hazırlanması, 0,4350mmol), diizopropil etil amin (0,0757 mi, 0,4350 mmol) ve 4: diklorometan ve dimetilformamid 1 karışımı ile gerçekleştirilmektedir. Bu sistein bağlama KOKTEYLİ sırlı şırınga ekleyin ve hafifçe 6 saat çalkalanır. Daha önce tarif edilen protokol kullanılarak yıkanır. </li><li> % 20 piperidin ile yıkama ile, Fmoc bileşeni uzaklaştırılarak elde edilmiş, (-) ninhidrin testi ile bağlanması kontrol edin. Ninhidrin testi (+) kullanarak amin ücretsiz terminali doğrulayın. </li></ol></li><li> Reçineden 1 yarılması. <ol><li> Bir TFA çözeltisi (9.45 mi), su (0.25 mi), 1,2-etanditiol (0.25 mi) ve triizopropil silan (0.1 mi) yapmak şırınga ekleyin ve 4 saat için hafifçe çalkalanır. </li><li> Bir Eppendorf tüpü içinde elde edilen kırmızı-kahverengi bir çözelti toplayın ve yavaş yavaş bir hava akımı kullanılarak TFA buharlaşır. </li><li> Soğuk dietil eter ekleyin (~ 15 mi) Eppendorf tüpüne narin ajitasyon oluşturacak olan, 1 çökeltildi. Santrifüj ile ürünü (1 g, 5 dakika) izole edin. Tdietil eter yıkama (~ 60 ml toplam) ve santrifüj tavuk tekrar çevrimi, kırmızı / kahverengi bir katı olarak 1 elde edildi. </li></ol></li></ol> 2. Karakterizasyonu ve 1 Analizi <ol><li> Kimlik 1 H (16 tarama) ve dötere metanol (300 ul) ve ESI-MS analizi 13 ° C NMR (512 tarama) ile, Şekil 2&#39;de gösterilen bağlantı ve bileşim ile uyumlu olduğunu kontrol edin. Aşağıdaki sonuçlar bekliyoruz: 1H-NMR spektrumu (CD3OD) δ / ppm: 1,407-1,684 (m, 6H), 2.245 (t, 2H), 2,665-3,150 (m, 12H), 4.015 (t, 1 H), 4.104 (d, 2H ), 4,274 (k, 1 H), 4.426 (d, 2H), 4,479 (k, 1 H), 4,595 (t, 1 H) ve 13 ° C NMR spektrum (CD3OD) δ / ppm: 24,644 (CH2), 25,472 (CH2), 28,051 (CH2), 28,300 (CH2), 35,474 (CH2), 38,698 (CH2), 39,241 (CH2), 39,717 (CH2), 55,340 / 55,538 (Co-halka), 60,286 (CıLH), 61,964 (CH), 62,521 / 62,821 (Co-bağ), 66,038 / 66,170 (Co-bağ), 69,153 / 69,328 (Cp-bağ), 71,468 / 71,593 (Co-bağ), 76,466 (CH), 171,770 (C = O), 175,361 (C = O). ESI-MS (m / z): Bulunan: 639.00 [1 + Na] +, teorik: 639,1 [1 + Na] + HR-MS (m / z): Bulunan: 617,2049 [1 + H] +, teorik: 617.1622 [1 + H] +. </li><li> HPLC, izole 1 bileşimini onaylamak için element analizi yapın. Bir C8 ile yürütmek HPLC kromatogramları, 0.5 ml / dk&#39;lık bir akış hızında% 100 MeOH ile ters fazlı kolon. Not: HPLC alıkoyma süreleri: 3,198-4,674 dak. </li></ol> Gold Yüzey üzerinde 1 3. İmmobilizasyonu <ol><li> Kesme polimer 2&#39;de ~ 0.25 kareler halinde altın slaytlar destekli. </li><li> 1 (~ 1 mm) bir DI su çözeltisi ile bir 50 ml beher doldurun. </li><li> Beher altın slayt ekleyin ve bir saat camı ile kaplayın. Tümakış cam slayt, herhangi bir çalkalama ile oda sıcaklığında O / N inkübe edilmesi. </li><li> Çözelti altın slayt çıkarın ve havada kuru izin. </li><li> 1 hareketsiz gözlemlemek için bir tarama elektron mikroskopu (ya da eşdeğeri) kullanılarak, elektron mikroskobu görüntülerini taramak elde edilir. </li></ol>

The authors have nothing to disclose.

asimetrik ferosen türevlerinin sentezi çözeltisi içinde zordur. Örneğin, çözelti, arzu edilen ürün (% 20 den az) olarak düşük miktarlarda ürün olarak sonuçlanmıştır 1 üretmek için çalışır. Benzer şekilde, 1&#39;-amino-ferrosen karboksilik asit (sans Fmoc) ve reçine bağlı biotini kullanan reaksiyonlar Baristic ark polimerize ürünle tutarlı çözünmeyen bir ürün ile sonuçlanmıştır. ve en az bir ürün. 47 Bu da Ferrocenenin ile komplike v...

Biyosensörler seçici analiz için platform olarak biyomoleküler tanıma teknolojisini kullanır ve kendi özgüllüğü, hız ve düşük maliyetli için kullanılan küçük cihazlardır. Biyomoleküllerin tespiti için elektrokimyasal biyosensörler nedeniyle basitlik, maliyet etkinliği ve yüksek hassasiyet bu alanın ön planda bulunmaktadır. Bu sensörlerin 1,3 genel anatomisi ilgi biyolojik marker için spesifik bir tanıma molekülü ile donatılmış bir elektrod olup . Tanıma molekülü tarafından bir biyolojik bağlanması, basit bir ölçümü ile tespit edilebilir potansiyel ya da mevcut yerel bir değişim ile sonuçlanır. Enzimler 4-8 antikorları, 9-12 tüm hücreleri, 13-16 reseptörleri, 17-20 peptidler 21-23 ve DNA 24 ve büyük ölçüde daha büyük, biyolojik moleküller odaklanmıştır değişebilir tanıma parçasını Bugüne kadar. 25-28 Araştırma Bu alanda çalışmalar İmmunosensörler whe üzerinde yoğunlaşmış olmasıbir immünoglobulin bir redoks aktif çekirdeği ile hareketsiz hale getirilmiştir (örneğin ferrosen gibi) ve ilgilenilen bir antikoru belirlemek için kullanılan yeniden. Bu çalışmalar antijen / antikor kullanımından kaynaklanan komplikasyonlar kaynaklanan nedeniyle zayıf hassasiyet ve zaman tüketimi, klinik uygulamalar dışında tutulmuştur. 1,3 Büyüyen dikkat biyomedikal küçük moleküllerin tespit (az 1 kg / mol) odaklanmıştır , gıda ve ulusal güvenliğin yanı sıra çevre faiz. 29 biyosensör cihazların en iyi bilinen örnekleri cep boyutunda amperometik metre bağlanmış ekran baskılı enzim elektrotları sahip self-test glukoz monitörleri vardır. Bu sistemler, tipik haliyle glukoz oksidasyon reaksiyonu tarafından üretilen yükün toplam miktarı, belirli bir süre boyunca ölçülür bir kulometrik bir yöntem kullanmaktadır. Menkul cihazlar, taşınabilir, sağlam ve olmalıdır büyük nüfus için uyduruk faydalanmak için el. Ferroken gibi redoks etiketleri necessa vardırEn biyomarkırlar özünde elektrokimyasal olarak aktif değil gibi ry çözeltide biyomarkerların veya küçük moleküllerin elektrokimyasal algılanmasını sağlamak için. 30-38 Ferrosen elektrokimyasal biyosensörler entegrasyon için mükemmel bir seçimdir elektrokimya için altın standart, bir organometalik moleküldür. Ferrosen-tabanlı redoks aktif türler zaten nedeniyle küçük boyutu, iyi bir istikrar, uygun sentetik erişimi kolay kimyasal modifikasyonu, göreceli Lipofillik ve redoks ayar kolaylığı büyük ilgi topladı. 3,30-42 Küçük moleküller var ferrosen çekirdek dayalı metal iyonları ve küçük moleküller detektör olarak yaygın şekilde kullanılmıştır. Biyomoleküller gibi daha büyük türlerin hedef 32-38,43 sistemleri elektrokimyasal yüzeyine gömülü olan ferrosen türevleri, büyük antikorlara veya immünoglobülin eki kullanmışlardır. 1,3,39 Her durumda, 44, potansiyel ve akım intensiFe III / Fe II redoks çiftinin Ty Böylece analit molekül mevcudiyetine işaret eden, yeni bir spektroskopik sap üretmeden, molekül birleştirme üzerine değiştirilmiştir. Bu değişiklik siklopentadienil halkaları pi-sistem ve demir D-orbitalleri arasında meydana kapsamlı örtüşme kaynaklanmaktadır. Pi-sistem değiştirilirse, yani, derive ya, ardından yörünge etkileşimi olacak, sırayla, değişim tepki gösterdi. Bu, Fe çekirdek etkiler ve demir III / Fe II çift potansiyel bir kayma olarak gözlenebilir. 40,45,46 Bu özellikler, bir elektrokimyasal bağışıklık ya da biyo-sensörün niceleme madde olarak kullanım için bu tür bir sistem cazip hale getirmektedir. Biyosensör kapasiteleri için özel ferrosen ihtiva eden sistemlerin üretilmesi amacıyla, bir hedef molekül için spesifik biyo-reseptörü ile bir Cp halkasının değiştirme ve elektrokimyasal okuma veya elektroda bir molekül halata gibi Cp halkasının kullanılması en uygunudurTrode (Şekil 1). Bu asimetrik ferrosen türevlerinin sentezi yan reaksiyonların ve moleküller arası çapraz bağlanma üzerine oluşan dimerik ve polimerik türlerinin oluşumu sebebi ile zorlanır. 47 Bununla birlikte, bir amid bağı üreten birleştirme kimyası biyolojik bileşenleri gibi ilgili ferrosen basit türevler sağlamak için en kısa yol olduğu peptidler ve bunların metabolitleri gibi. Bu nedenle, ilk olarak peptid sentezi için Merrifield tarafından 1950&#39;li yıllarda geliştirilen bir katı faz teknikleri ferrosen içeren organometalik bileşikler için uygulanabilir. Yer alır dik ikame 1&#39;-Fmoc-amino-ferrosen-1-karboksilik asit molekülünün, bir alıcı parçasını (biyotin), elektrokimyasal okuma (ferrosen) ve hareketsiz kılma-bağlayıcı bileşen (sistein) içeren bir ferrosen sistemi kullanılmasıyla inşa ve burada ayrıntılı olarak. Bu biyo-konjugat sentezi altın yüzeyinde immobilizasyon için kanıtların yanı sıra ele alınmaktadır. Bu çalışma Temsilci VekiliBiotin, ferrosen ve bir altın yüzeye immobilizasyon için bir amino asitten oluşan bir sistemin birinci sunum ts.

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr>
			<td>Biotin Novatag Resin</td>
			<td>NovaBiochem</td>
			<td>8550510001</td>
			<td></td>
		</tr>
		<tr>
			<td>TORVIQ 10ML LUER LOCK FRITTED SYRINGE</td>
			<td>Fisher</td>
			<td>NC9299151</td>
			<td></td>
		</tr>
		<tr>
			<td>piperdine</td>
			<td>Acros</td>
			<td>P/3520/PB05</td>
			<td></td>
		</tr>
		<tr>
			<td>ninhydrin test</td>
			<td>Sigma-Aldrich</td>
			<td>60017-1ea</td>
			<td></td>
		</tr>
		<tr>
			<td>1&#8217;-Fmoc-amino-ferrocene-1-carboxylic acid</td>
			<td>Omm Scientific</td>
			<td>Special Order</td>
			<td></td>
		</tr>
		<tr>
			<td>1-&#8203;Hydroxybenzotriazole hydrate</td>
			<td>Sigma-Aldrich</td>
			<td>157260-25G</td>
			<td></td>
		</tr>
		<tr>
			<td>N,N&#8242;-Diisopropylcarbodiimide</td>
			<td>Sigma-Aldrich</td>
			<td>D125407-5G</td>
			<td></td>
		</tr>
		<tr>
			<td>N,N-&#8203;Diisopropylethylamine</td>
			<td>Sigma-Aldrich</td>
			<td>496219-100ML</td>
			<td></td>
		</tr>
		<tr>
			<td>Fmoc-Cys(Trt)-OH</td>
			<td>Novabiochem</td>
			<td>8520080025</td>
			<td></td>
		</tr>
		<tr>
			<td>trifluoroacetic acid</td>
			<td>Sigma-Aldrich</td>
			<td>T5408</td>
			<td></td>
		</tr>
		<tr>
			<td>1,2-ethanedithiol</td>
			<td>Sigma-Aldrich</td>
			<td>2930</td>
			<td></td>
		</tr>
		<tr>
			<td>triisopropyl silane</td>
			<td>Sigma-Aldrich</td>
			<td>233781</td>
			<td></td>
		</tr>
		<tr>
			<td>Eppendorf tubes (20 mL)</td>
			<td>any source</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>methanol</td>
			<td>any source</td>
			<td></td>
			<td>dry with molecular sieves prior to use &#38; store in 100 mL media bottle for easy usage.</td>
		</tr>
		<tr>
			<td>dichloromethane</td>
			<td>any source</td>
			<td></td>
			<td>dry with molecular sieves prior to use &#38; store in 100 mL media bottle for easy usage.</td>
		</tr>
		<tr>
			<td>dimethylformamide</td>
			<td>any source</td>
			<td></td>
			<td>dry with molecular sieves prior to use &#38; store in 100 mL media bottle for easy usage.</td>
		</tr>
		<tr>
			<td>centrifuge</td>
			<td>any source</td>
			<td></td>
			<td></td>
		</tr>
	</tbody>
</table>

synthetic methodology for asymmetric ferrocene derived bio-conjugate systems via solid phase resin-based methodology

Erken teşhis çoğu hastalıkların başarılı tedavisi için bir anahtardır, ve birçok kanser türlerinin tanı ve tedavisi için özellikle zorunludur. kullanılan en yaygın teknikler Manyetik Rezonans Görüntüleme (MRG), Pozitron Emisyon Topografi (PET) ve Bilgisayarlı Topografya (BT) gibi görüntüleme yöntemleri ve hastalığın fiziksel yapısını anlamak için en uygun ama sadece bir kez yapılan her dört edilebilir olan görüntüleme ajanları ve genel maliyet kullanımı nedeniyle altı hafta. Zihin, bu tür tedavi protokolleri devrim olur, hastalık ve / veya klinisyenin ofisinde tedavinin etkinliği aşamasına değerlendirmek ve zamanında bunu biyosensörlere gibi teknikler, &quot;bakım noktası&quot; geliştirilmesi. 1. As ile bu biyolojik ilgili moleküllerin 2 tespiti için ferosen tabanlı biyosensörler keşfetmek için bir araç, yöntemler burada tarif edilen ferrosen-biyotin biyo-konjugatlarını üretmek için geliştirilmiştir. Bu rapor, altın yüzey üzerinde immobilize edilebilir bir biyotin-ferrosen-sisteyin sistemi üzerinde durulacaktır.

1 reçineye bağlı bir şekilde, Şekil 2 &#39;de gösterilmiştir. ferrosen bileşeni kovalent bağlanması ile demir emilimini karşı sürekli yıkama ile kalıcı ve kompleks ihtiva eden bir hareketsiz demir göstergesidir reçine boncukları turuncu bir renk tonu meydana getirir bir reçine tanesi PEG bileşeni. 1 reçineden serbest form reçine boncukları renk aynıdır. Reçineden boncuklardan bileşiği çıkarılmasının ardından, yöntem elde edilen saflı...

Watch this Scientific Journal Video about Synthetic Methodology for Asymmetric Ferrocene Derived Bio-conjugate Systems via Solid Phase Resin-based Methodology at JoVE.com

Synthetic Methodology for Asymmetric Ferrocene Derived Bio-conjugate Systems via Solid Phase Resin-based Methodology

The synthesis of asymmetric species of ferrocene is challenging using solution techniques. This report focuses on the methods carried out to produce a ferrocene-biotin bioconjugate using facile and clean reactions accomplished via solid-phase synthesis. Incorporation of a thiolate moiety is shown to impart the ability for immobilization on gold surfaces.

Katı Faz Reçine-tabanlı Metodoloji aracılığıyla Asimetrik Ferrosen Türetilmiş Bio-konjuge Sistemleri Sentetik Metodoloji

Early detection is a key to successful treatment of most diseases, and is particularly imperative for the diagnosis and treatment of many types of cancer. ...

synthetic-methodology-for-asymmetric-ferrocene-derived-bio-conjugate

Research

JoVE Journal

Chemistry

9.6K Görüntüleme.  Texas Christian University. The synthesis of asymmetric species of ferrocene is challenging using solution techniques. This report focuses on the methods carried out to produce a ferrocene-biotin bioconjugate using facile and clean reactions accomplished via solid-phase synthesis. Incorporation of a thiolate moiety is shown to impart the ability for immobilization on gold surfaces.

Video: Synthetic Methodology for Asymmetric Ferrocene Derived Bio-conjugate Systems via Solid Phase Resin-based Methodology

High-pressure Sapphire Cell for Phase Equilibria Measurements of CO2/Organic/Water Systems

The high pressure sapphire cell apparatus was constructed to visually determine the composition of multiphase systems without physical sampling. Specifically, the sapphire cell enables visual data collection from multiple loadings to solve a set of material balances to precisely determine phase composition. Ternary phase diagrams can then be established to determine the proportion of each component in each phase at a given condition. In principle, any ternary system can be studied although ternary systems (gas-liquid-liquid) are the specific examples discussed herein. For instance, the ternary THF-Water-CO2 system was studied at 25 and 40&#160;&#176;C and is described herein. Of key importance, this technique does not require sampling. Circumventing the possible disturbance of the system equilibrium upon sampling, inherent measurement errors, and technical difficulties of physically sampling under pressure is a significant benefit of this technique. Perhaps as important, the sapphire cell also enables the direct visual observation of the phase behavior. In fact, as the CO2 pressure is increased, the homogeneous THF-Water solution phase splits at about 2 MPa. With this technique, it was possible to easily and clearly observe the cloud point and determine the composition of the newly formed phases as a function of pressure.
The data acquired with the sapphire cell technique can be used for many applications. In our case, we measured swelling and composition for tunable solvents, like gas-expanded liquids, gas-expanded ionic liquids and Organic Aqueous Tunable Systems (OATS)1-4. For the latest system, OATS, the high-pressure sapphire cell enabled the study of (1) phase behavior as a function of pressure and temperature, (2) composition of each phase (gas-liquid-liquid) as a function of pressure and temperature and (3) catalyst partitioning in the two liquid phases as a function of pressure and composition. Finally, the sapphire cell is an especially effective tool to gather accurate and reproducible measurements in a timely fashion.

High-pressure Sapphire Cell for Phase Equilibria Measurements of CO2/Organic/Water Systems

The high pressure sapphire cell apparatus is a unique tool to study, without sampling, phase behavior under a wide range of pressures. Using a cathetometer, very precise volume measurements can be recorded to measure liquid expansion and phase composition. Thus, this synthetic method enables the study of (1) phase equilibria of multi-component mixtures and (2) the partition behavior of catalyst or model compounds as a function of pressure.

CO Faz Dengeleri Ölçümleri için yüksek basınçlı Safir Hücre<sub&gt; 2</sub&gt; / / Organik Su Sistemleri

The high pressure sapphire cell apparatus was constructed to visually determine the composition of multiphase systems without physical sampling. ...

Kimya

Stabilizing Hepatocellular Phenotype Using Optimized Synthetic Surfaces

Currently, one of the major limitations in cell biology is maintaining differentiated cell phenotype. Biological matrices are commonly used for culturing and maintaining primary and pluripotent stem cell derived hepatocytes. While biological matrices are useful, they permit short term culture of hepatocytes, limiting their widespread application. We have attempted to overcome the limitations using a synthetic polymer coating. Polymers represent one of the broadest classes of biomaterials and possess a wide range of mechanical, physical and chemical properties, which can be fine-tuned for purpose. Importantly, such materials can be scaled to quality assured standards and display batch-to-batch consistency. This is essential if cells are to be expanded for high through-put screening in the pharmaceutical testing industry or for cellular based therapy. Polyurethanes (PUs) are one group of materials that have shown promise in cell culture. Our recent progress in optimizing a polyurethane coated surface, for long-term culture of human hepatocytes displaying stable phenotype, is presented and discussed.

This article will focus on developing polymer coated surfaces for long-term, stable culture of stem cell derived human hepatocytes.

Optimize Sentetik Yüzeyler Hepatosellüler Fenotip kullanma Stabilize

Currently, one of the major limitations in cell biology is maintaining differentiated cell phenotype. Biological matrices are commonly used for culturing ...

X-ray Powder Diffraction in Conservation Science: Towards Routine Crystal Structure Determination of Corrosion Products on Heritage Art Objects

The crystal structure determination and refinement process of corrosion products on historic art objects using laboratory high-resolution X-ray powder diffraction (XRPD) is presented in detail via two case studies.
The first material under investigation was sodium copper formate hydroxide oxide hydrate, Cu4Na4O(HCOO)8(OH)2&#8729;4H2O (sample 1) which forms on soda glass/copper alloy composite historic objects (e.g., enamels) in museum collections, exposed to formaldehyde and formic acid emitted from wooden storage cabinets, adhesives, etc. This degradation phenomenon has recently been characterized as &#34;glass induced metal corrosion&#34;.
For the second case study, thecotrichite, Ca3(CH3COO)3Cl(NO3)2&#8729;6H2O (sample 2), was chosen, which is an efflorescent salt forming needlelike crystallites on tiles and limestone objects which are stored in wooden cabinets and display cases. In this case, the wood acts as source for acetic acid which reacts with soluble chloride and nitrate salts from the artifact or its environment.
The knowledge of the geometrical structure helps conservation science to better understand production and decay reactions and to allow for full quantitative analysis in the frequent case of mixtures.

Modern high resolution X-ray powder diffraction (XRPD) in the laboratory is used as an efficient tool to determine crystal structures of long-known corrosion products on historic objects.

Koruma Bilimi X-ışını Toz Kırınım: Miras Sanat Objects Korozyon Ürünleri Rutin Kristal Yapı Tayini Doğru

The crystal structure determination and refinement process of corrosion products on historic art objects using laboratory high-resolution X-ray powder ...

Measurement of Particle Size Distribution in Turbid Solutions by Dynamic Light Scattering Microscopy

A protocol for measuring polydispersity of concentrated polymer solutions using dynamic light scattering is described. Dynamic light scattering is a technique used to measure the size distribution of polymer solutions or colloidal particles. Although this technique is widely used for the assessment of polymer solutions, it is difficult to measure the particle size in concentrated solutions due to the multiple scattering effect or strong light absorption. Therefore, the concentrated solutions should be diluted before measurement. Implementation of the confocal optical component in a dynamic light scattering microscope1 helps to overcome this barrier. Using such a microscopic system, both transparent and turbid systems can be analyzed under the same experimental setup without a dilution. As a representative example, a size distribution measurement of a temperature-responsive polymer solution was performed. The sizes of the polymer chains in an aqueous solution were several tens of nanometers at a temperature below the lower critical solution temperature (LCST). In contrast, the sizes increased to more than 1.0 &#181;m when above the LCST. This result is consistent with the observation that the solution turned turbid above the LCST.

A protocol for the direct measurement of particle size distribution in concentrated solutions using dynamic light scattering microscopy is presented.

Dinamik ışık saçılımı Mikroskopi Bulanık Çözümleri Tane Büyüklüğü Dağılımının Ölçümü

A protocol for measuring polydispersity of concentrated polymer solutions using dynamic light scattering is described. Dynamic light scattering is a ...

Integration of Miniaturized Solid Phase Extraction and LC-MS/MS Detection of 3-Nitrotyrosine in Human Urine for Clinical Applications

Free 3-nitrotyrosine (3-NT) has been extensively used as a possible biomarker for oxidative stress. Increased levels of 3-NT have been reported in a wide variety of pathological conditions. However, existing methods lack the sufficient sensitivity and/or specificity necessary to measure the low endogenous level of 3-NT reliably and are too cumbersome for clinical applications. Hence, analytical improvement is urgently needed to accurately quantify the levels of 3-NT and verify the role of 3-NT in pathological conditions. This protocol presents the development of a novel liquid chromatography tandem mass spectrometry (LC-MS/MS) detection combined with a miniaturized solid phase extraction (SPE) for the rapid and accurate measurement of 3-NT in human urine as a non-invasive biomarker for oxidative stress. SPE using a 96-well plate markedly simplified the process by combining sample cleanup and analyte enrichment without tedious derivatization and evaporation steps, reducing solvent consumption, waste disposal, risk of contamination and overall processing time. The employment of 25 mM ammonium acetate (NH4OAc) at pH 9 as the SPE elution solution substantially enhanced the selectivity. Mass spectrometry signal response was improved through adjustment of the multiple reaction monitoring (MRM) transitions. Use of 0.01% HCOOH as additive on a pentafluorophenyl (PFP) column (150 mm x 2.1 mm, 3 &#181;m) improved signal response another 2.5-fold and shortened the overall run time to 7 min. A lower limit of quantitation (LLOQ) of 10 pg/mL (0.044 nM) was achieved, representing a significant sensitivity improvement over the reported assays. This simplified, rapid, selective and sensitive method allows two plates of urine samples (n = 192) to be processed in a 24 h time-period. Considering the markedly improved analytical performance, and non-invasive and inexpensive urine sampling, the proposed assay is beneficial for pre-clinical and clinical studies.

A selective and sensitive liquid chromatography tandem mass spectrometry (LC-MS/MS) method coupled with an efficient solid phase extraction on a mixed-mode cation-exchange (MCX) 96-well microplate was developed for the measurement of free 3-nitrotyrosine (3-NT) in human urine with high throughput, which is suitable for clinical applications.

Klinik Uygulamalar İçin İnsan İdrarında 3-Nitrotirosinin Minyatür Katı Faz Çıkarma ve LC-MS / MS Algılamasının Entegrasyonu

Free 3-nitrotyrosine (3-NT) has been extensively used as a possible biomarker for oxidative stress. Increased levels of 3-NT have been reported in a wide ...

Application and Methodology of the Non-destructive 19F Time-domain NMR Technique to Measure the Content in Fluorine-containing Drug Products

Here, we describe a protocol developed by our group that uses low-field fluorine-19 (19F) time-domain (TD) nuclear magnetic resonance (NMR) to measure the average content of fluorinated drugs in their formulated drug product forms: tablets or capsules. This method is specific to fluorinated drugs because it detects only the content of fluorine, avoiding interference from the excipients that lack fluorine. The advantages of measuring the active content of fluorinated drugs using low-field 19F TD-NMR versus high-field 19F solid-state (SS) NMR are the simplicity of the method; the low cost; and the non-destructive nature of the technique, with all samples recoverable in intact forms (e.g., powders, tablets, and capsules), making this technique affordable for any laboratory.
We have tested the method with three fluorinated drug products available on the market - cinacalcet, lansoprazole, and ciprofloxacin - with doses ranging from 15 to 500 mg. The results of the analyses, measured by low-field 19F TD-NMR, supported the reported label claims for the average drug content.
Based on the simplicity and reproducibility of the analysis, we envision this methodology being implemented in any laboratory, including manufacturing plants, as a process analytical technology (PAT) tool in the pharmaceutical industry.

Application and Methodology of the Non-destructive 19F Time-domain NMR Technique to Measure the Content in Fluorine-containing Drug Products

A simple and non-destructive technique that measures the average content of drug substances in formulated drug products containing fluorine using low-field fluorine-19 (19F) time-domain (TD) nuclear magnetic resonance (NMR) is presented here. The technique can be applied to the development and manufacturing of drugs in the pharmaceutical industry.

Uygulama ve tahribatsız 19F saat-alan NMR tekniği metodolojisi Flor içeren ilaç ürünleri içeriğindeki ölçmek için

Here, we describe a protocol developed by our group that uses low-field fluorine-19 (19F) time-domain (TD) nuclear magnetic resonance (NMR) to measure the ...

Phase Behavior of Charged Vesicles Under Symmetric and Asymmetric Solution Conditions Monitored with Fluorescence Microscopy

Phase-separated giant unilamellar vesicles (GUVs) exhibiting coexisting liquid-ordered and liquid-disordered domains are a common biophysical tool to investigate the lipid raft hypothesis. Numerous studies, however, neglect the impact of physiological solution conditions. On that account, the current work presents the effect of high-salinity buffer and trans-membrane solution asymmetry on liquid-liquid phase separation in charged GUVs grown from dioleylphosphatidylglycerol, egg sphingomyelin, and cholesterol. The effects were studied under isothermal and varying temperature conditions.
We describe equipment and experimental strategies applicable for monitoring the stability of coexisting liquid domains in charged vesicles under symmetric and asymmetric high-salinity solution conditions. This includes an approach to prepare charged multicomponent GUVs in high-salinity buffer at high temperatures. The protocol entails the option to perform a partial exchange of the external solution by a simple dilution step while minimizing the vesicle dilution. An alternative approach is presented utilizing a microfluidic device that allows for a complete external solution exchange. The solution effects on phase separation were also studied under varying temperatures. To this end, we present the basic design and utility of an in-house built temperature control chamber. Furthermore, we reflect on the assessment of the GUV phase state, pitfalls associated with it and how to circumvent them.

Experiments on phase separated giant unilamellar vesicles (GUVs) frequently neglect physiological solution conditions. This work presents approaches to study the effect of high-salinity buffer on liquid-liquid phase separation in charged multicomponent GUVs as a function of trans-membrane solution asymmetry and temperature.

Şarj edilmiş veziküller Floresans mikroskobu ile izlenen simetrik ve asimetrik çözüm koşullarda davranışını faz

Phase-separated giant unilamellar vesicles (GUVs) exhibiting coexisting liquid-ordered and liquid-disordered domains are a common biophysical tool to ...

Protocol for the Solid-phase Synthesis of Oligomers of RNA Containing a 2'-O-thiophenylmethyl Modification and Characterization via Circular Dichroism

Solid-phase synthesis has been used to obtain canonical and modified polymers of nucleic acids, specifically of DNA or RNA, which has made it a popular methodology for applications in various fields and for different research purposes. The procedure described herein focuses on the synthesis, purification, and characterization of dodecamers of RNA 5&#39;-[CUA CGG AAU CAU]-3&#39; containing zero, one, or two modifications located at the C2&#39;-O-position. The probes are based on 2-thiophenylmethyl groups, incorporated into RNA nucleotides via standard organic synthesis and introduced into the corresponding oligonucleotides via their respective phosphoramidites. This report makes use of phosphoramidite chemistry via the four canonical nucleobases (Uridine (U), Cytosine (C), Guanosine (G), Adenosine (A)), as well as 2-thiophenylmethyl functionalized nucleotides modified at the 2&#39;-O-position; however, the methodology is amenable for a large variety of modifications that have been developed over the years. The oligonucleotides were synthesized on a controlled-pore glass (CPG) support followed by cleavage from the resin and deprotection under standard conditions, i.e., a mixture of ammonia and methylamine (AMA) followed by hydrogen fluoride/triethylamine/N-methylpyrrolidinone. The corresponding oligonucleotides were purified via polyacrylamide electrophoresis (20% denaturing) followed by elution, desalting, and isolation via reversed-phase chromatography (Sep-pak, C18-column). Quantification and structural parameters were assessed via ultraviolet-visible (UV-vis) and circular dichroism (CD) photometric analysis, respectively. This report aims to serve as a resource and guide for beginner and expert researchers interested in embarking in this field. It is expected to serve as a work-in-progress as new technologies and methodologies are developed. The description of the methodologies and techniques within this document correspond to a DNA/RNA synthesizer (refurbished and purchased in 2013) that uses phosphoramidite chemistry.

Protocol for the Solid-phase Synthesis of Oligomers of RNA Containing a 2&#039;-O-thiophenylmethyl Modification and Characterization via Circular Dichroism

This article provides a detailed procedure on the solid-phase synthesis, purification, and characterization of dodecamers of RNA modified at the C2&#39;-O-position. UV-vis and circular dichroism photometric analyses are used to quantify and characterize structural aspects, i.e., single-strands or double-strands.

Bir 2&#39;-amino asit içeren RNA Oligomerlerinin Katı Faz Sentezi Protokolü<em&gt; Ç</em&gt; Tiyofenilmetil Değiştirme ve Sirküler Dikroizm ile Karakterizasyonlar

Solid-phase synthesis has been used to obtain canonical and modified polymers of nucleic acids, specifically of DNA or RNA, which has made it a popular ...

Characterization of Synthetic Polymers via Matrix Assisted Laser Desorption Ionization Time of Flight (MALDI-TOF) Mass Spectrometry

There are many techniques that can be employed in the characterization of synthetic homopolymers, but few provide as useful of information for end group analysis as matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS). This tutorial demonstrates methods for optimization of the sample preparation, spectral acquisition, and data analysis of synthetic polymers using MALDI-TOF MS. Critical parameters during sample preparation include the selection of the matrix, identification of an appropriate cationization salt, and tuning the relative proportions of the matrix, cation, and analyte. The acquisition parameters, such as mode (linear or reflector), polarization (positive or negative), acceleration voltage, and delay time, are also important. Given some knowledge of the chemistry involved to synthesize the polymer and optimizing both the data acquisition parameters and the sample preparation conditions, spectra should be obtained with sufficient resolution and mass accuracy to enable the unambiguous determination of the end groups of most homopolymers (masses below 10,000) in addition to the repeat unit mass and the overall molecular weight distribution. Though demonstrated on a limited set of polymers, these general techniques are applicable to a much wider range of synthetic polymers for determining mass distributions, though end group determination is only possible for homopolymers with narrow dispersity.

Characterization of Synthetic Polymers via Matrix Assisted Laser Desorption Ionization Time of Flight MALDI-TOF Mass Spectrometry

A protocol for the matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS) characterization of synthetic polymers is described including the optimization of sample preparation, spectral acquisition, and data analysis.

Matris ile sentetik polimerler karakterizasyonu Lazer Desorpsiyon iyonlaşma zaman uçuş (MALDI-TOF) kütle spektrometresi destekli

There are many techniques that can be employed in the characterization of synthetic homopolymers, but few provide as useful of information for end group ...

Solid-phase Synthesis of [4.4] Spirocyclic Oximes

A convenient synthetic route for spirocyclic heterocycles is well sought after due to the molecule&#39;s potential use in biological systems. By means of solid-phase synthesis, regenerating Michael (REM) linker strategies, and 1,3-dipolar cycloaddition, a library of structurally similar heterocycles, both with and without a spirocyclic center, can be constructed. The main advantages of the solid-support synthesis are as follows: first, each reaction step can be driven to completion using a large excess of reagents resulting in high yields; next, the use of commercially available starting materials and reagents keep the costs low; finally, the reaction steps are easy to purify via simple filtration. The REM linker strategy is attractive because of its recyclability and traceless nature. Once a reaction scheme is completed, the linker can be reused multiple times. In a typical solid-phase synthesis, the product contains either a part of or the whole linker, which can prove undesirable. The REM linker is &#34;traceless&#34; and the point of attachment between the product and the polymer is indistinguishable. The high diastereoselectivity of the intramolecular 1,3-dipolar cycloaddition is well documented. Limited by the insolubility of the solid support, the reaction progression can only be monitored by a change in the functional groups (if any) via infrared (IR) spectroscopy. Thus, the structural identification of intermediates cannot be characterized by conventional nuclear magnetic resonance (NMR) spectroscopy. Other limitations to this method stem from the compatibilities of the polymer/linker to the desired chemical reaction scheme. Herein we report a protocol that allows for the convenient production of spirocyclic heterocycles that, with simple modifications, can be automated with high-throughput techniques.

Here we present a protocol to demonstrate an efficient method for the synthesis of spirocyclic heterocycles. The five-step process utilizes solid-phase synthesis and regenerating Michael linker strategies. Generally difficult to synthesize, we present a customizable method for the synthesis of spirocyclic molecules otherwise inaccessible to other modern approaches.

Katı faz [4.4] Spirocyclic Oximes sentezi

A convenient synthetic route for spirocyclic heterocycles is well sought after due to the molecule&#39;s potential use in biological systems. By means of ...