Este trabalho foi financiado pela Fundação Swiss National Science (Grants n ° PZ00P2_126430 / 1 e PZ00P2_144595). Prof C. Leumann é reconhecido agradecimento por fornecer o espaço e equipamentos de laboratório, bem como pelo seu apoio constante. Ms. Sue Knecht é reconhecido por discussões frutíferas.

1. Síntese dos nucleósidos modificados Trisfosfatos A abordagem sintética escolhido segue o procedimento desenvolvido por Ludwig e Eckstein uma vez que este método é geralmente fiável e conduz a muito poucos sub-produtos secundários (Figura 1A) 39. <ol><li> Coevaporate do nucleósido apropriadamente protegido-3&#39;-OAc (tipicamente 0,1 mmol) duas vezes com piridina anidra (2 ml) e, em seguida, seco sob vácuo durante a noite. Ao mesmo tempo, o pirofosfato de tributilamónio seca (0,13 mmol) sob vácuo durante a noite. </li><li> Dissolve-se o nucleósido, num mínimo de piridina seca (0,2 ml) e adiciona-dioxano seco (0,4 ml) como co-solvente. Finalmente, adicionar 2-cloro-1 ,3,2-benzodioxaphosphorin-4-ona (0,11 mmol) e deixa-se reagir à temperatura ambiente durante 45 min. Nota: É de salientar que um cuidado especial deve ser tomado com o 2-cloro-1 ,3,2-benzodioxaphosphorin-4-um reagente. Na verdade, mesmo de armazenamento deste reagente sob uma atm de gás inerteaqui não é suficiente para evitar a sua decomposição. Assim, o sólido branco que se formou neste decomposição pode e deve ser raspada antes de ser utilizado. </li><li> Prepara-se uma solução de pirofosfato de tributilamónio em DMF seca (0,17 mL) e tributilamina recém-destilada (58 ul; nunca adicionar crivos moleculares). Adicionar a solução resultante da mistura de reacção (um precipitado branco, mas aparece rapidamente desaparece) e deixa-se reagir à temperatura ambiente durante 45 min. </li><li> Prepara-se uma solução de iodo (0,16 mmol) em piridina (0,98 ml) e H2O (20 mL) e adiciona-se à mistura de reacção, a fim de oxidar o Pα (III) centro. Permitir que a solução escura resultante a agitar à temperatura ambiente durante 30 min. </li><li> Usar uma solução aquosa a 10% de NaS 2 O 3 para extinguir o excesso de I2. Remover o solvente sob vácuo (temperatura do banho de água do evaporador rotativo deve ser mantida abaixo de 30 ° C). Adicionar H 2 O (5 mL) e permitir que o mixture em repouso à temperatura ambiente durante 30 minutos para hidrolisar o agrupamento trifosfato cíclico. </li><li> Nesta fase, os grupos protectores são geralmente removidos (por exemplo, o 3&#39;-OAc e os grupos nas cadeias laterais de nucleobase). Consequentemente, adicionar NH 4 OH (30% em H2O, 10 ml) para o produto em bruto e agita-se durante 1,5 horas à temperatura ambiente, e remover o solvente sob vácuo. </li><li> Adicionar 2 ml de H 2 O e dividida em dois tubos. Adicionar 12 ml de uma solução a 2% de NaClO 4 em acetona e centrifugar (1000 x g) durante 30 min. Este procedimento é repetido mais uma vez. Esta precipitação permite a separação dos solventes e reagentes utilizados na síntese do trifosfato (que irá precipitar), simplificando assim a subsequente purificação por RP-HPLC substancialmente. </li><li> Após secagem ao ar do resíduo oleoso, gravar um espectro de 31 P-RMN do produto bruto (seguindo procedimentos padrão, ver também a Lista de Materiais e Figura 3) edissolvem-se em 4 ml de H 2 O. Nota: O procedimento sintético centra-se principalmente na geração de desoxinucleotídeos modificados, mas um procedimento muito semelhante pode ser aplicado para as suas contrapartidas de ARN (por simplesmente usando 2 &#39;, 3&#39;-bis-O-acetilado precursores). </li></ol> 2. A purificação por HPLC dos nucleósidos modificados Trisfosfatos <ol><li> Preparação de uma solução 1 M de bicarbonato de trietilamónio (BTEA): 40 <ol><li> Prepara-se uma solução de 1 mole de trietilamina (139 ml) em ≈ 600 ml de água destilada e filtrada H 2 O. </li><li> Borbulhar CO 2 (por meio de gelo seco e um borbulhador de gás) para dentro da solução sob agitação vigorosa, até que um pH de 7,6 foi atingido (isto levará, pelo menos, 10 horas). Esta solução pode ser armazenada na geladeira por até um mês. </li></ol></li><li> Purificação: <ol><li> Prepare duas soluções tampão do estoque 1 M: 2 l de TEAB 50 mM em água ultrapura (eluente A) umnd 1 L de 50 mM de TEAB em 50% de MeCN (eluente B). Desgaseifica ambos eluentes, sob vácuo e agitação durante 20 min (atenção é necessária de modo a não alterar o pH através da remoção de CO 2 durante a desgaseificação). </li><li> Prepara-se uma amostra analítica por dissolução de 10 ul do trifosfato bruto em 300 ml de H2O destilada e injectar no sistema de HPLC equipado com uma coluna RP semi-preparativa (C18) e com um gradiente que varia de 0-100% de B em 40 min (Figura 4). Ajustar o programa de acordo com a HPLC Rt do trifosfato (o que geralmente é o pico principal do cromatograma) e o difosfato (que tem um R ligeiramente inferior t). Purificar a mistura bruta usando essas condições e removendo frações iniciais que possam conter algum difosfato. </li><li> Combinar todas as fracções que contêm o produto e liof seco (que é o preferido para a evaporação no evaporador rotativo, a fim de minimizar a hidrólise do diphosph indesejadacomi). Coevaporate várias vezes com água ultrapura (para remover a trietilamina remanescente dos eluentes). Avaliar a pureza do trifosfato por RMN (1 H e ambos 31 P RMN) e MALDI-TOF por aplicação de protocolos padrão (ver Figura 5). Os rendimentos típicos obtidos por aplicação deste protocolo tipicamente estar na gama de 30-70%, dependendo do substrato. </li></ol></li></ol> 3. As reacções de extensão do primer e TdT Polimerização <ol><li> Etiquetagem da extremidade 5 &#39;do iniciador <ol><li> Misturar 30 pmol do iniciador apropriado (por exemplo, P1, Lista de Materiais) com 4 ul de tampão cinase 10x Polinucleótido (PNK), 3 ul de γ-[32 P]-ATP, 1 ul de PNK, e ddH2O (por num volume de reacção total de 40 ul). Incubar a mistura de reacção a 37 ° C durante 30 minutos e depois aquece-desactivar a quinase (10 min a 70 ° C). </li><li> Durante a reacção de marcação prepararuma coluna de Sephadex G10, ligando uma ponta de pipeta de 1 ml com a lã de vidro silanizada e enchendo a ponta com uma solução de G10 (a 10% em ddH2O, autoclavado). Girar para baixo e lavar três vezes com 500 ul de ddH2O e uma lavagem final com 50 ul DDH 2 O. Executar a mistura de reacção através do G10 (para remover o marcador radioactivo livre). </li><li> Gel de purificar (PAGE 20%) o primer radiomarcado e recuperar por aplicação do método de esmagamento e embeber (isto é, a eluição com 500 mL de uma solução aquosa contendo 1% de LiClO 4 e 1 mM de NEt 3 (pH 8) a 72 ° C durante 15 min). Precipitado em etanol e G10 dessalinizar o oligonucleótido eluída. </li></ol></li><li> Reacção de extensão de iniciador <ol><li> Hibridar 1 pmol de iniciador marcado radioactivamente P1, 10 pmol de iniciadores P1, e 10 pmol de molde T1 (Lista de Materiais) em tampão de reacção de 10x (fornecido pelo fornecedor da polimerase para ser usado), colocando o tube em (90-95 ° C) de água quente e por se deixar arrefecer gradualmente até à temperatura ambiente (durante 45 minutos). </li><li> Colocar o tubo em gelo e adicionar (por sua vez) o cocktail de dNTP (que contém tanto o modificadas e os trifosfatos naturais, 100 uM de concentração final) e 1 U de polimerase de ADN (Ventilação (exo -), de Klenow, ou Pwo N ° 9 m) e completar com água (para um volume de reacção total de 20 ul). Incubar à temperatura óptima de trabalho do enzima (por exemplo, 60 ° C durante 30 min, quando respiradouro (exo -) está a ser usado). </li><li> Adicionar 20 ul de solução de paragem (formamida (70%), ácido etilenodiaminotetracético (EDTA, 50 mM), azul de bromofenol (0,1%), xileno cianol (0,1%)), aquecer as amostras (95 ° C, 5 min), fresco para baixo (0 ° C), e resolver por electroforese em gel desnaturante de poliacrilamida. Visualize por phosphorimager. </li></ol></li><li> Polimerização TdT <ol><li> Diluir 7 pmol de de cadeia única, Sem rótulo cartilha P2 (Lista de Materiais), 1 pmol de primer radiomarcado em 1 ml de tampão TdT 10x. </li><li> Colocar o tubo em gelo e adicionar (por sua vez) o cocktail de dNTP (a uma concentração adequada compreendida entre 10 e 200 mM) e a polimerase de TdT (4 L). Incubar a 37 ° C durante 1 hora. Adicionar 10 ml da solução de paragem, aquecer as amostras (95 ° C, 5 min), arrefecer (0 ° C), e resolver por electroforese em gel desnaturante de poliacrilamida (PAGE 15%). Visualize por phosphorimager. </li></ol></li></ol> 4. PCR com nucleosídeos modificados Trisfosfatos <ol><li> Misturar 8 pmol de ambos os iniciadores directos e inversos com 0,5 pmol do modelo a ser amplificado. Adicionar 10x tampão de reacção e o cocktail de dNTP (para uma concentração final de 200 uM) e colocar o tubo em gelo. Adicionar 1 U de polimerase do ADN e completa com H 2 O para atingir um volume final de 20 ul. Transferir a mistura para um tubo de PCR e realizar 30 ciclos de PCR.</li><li> Diluir 6 mL com 6 mL de tampão de carregamento de sacarose 2x e resolver, através de agarose 2% (corados com brometo de etídio) eletroforese. Visualize por phosphorimager. </li></ol>

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A inclusão de modificações nos ácidos nucléicos é de interesse para inúmeras aplicações práticas, incluindo o desenvolvimento de agentes anti-senso e antigène 42,43, rotulagem e etiquetagem funcional de oligonucleotídeos 41, e em esforços para expandir o alfabeto genético 44-46. Alterações químicas e grupos funcionais são geralmente introduzidas em ácidos nucleicos por aplicação de protocolos de síntese em fase sólida padrão e automatizadas. No entanto, os blocos ...

<html> Trifosfato 5&#39;-nucleosídeos ((d) PNT) representam uma classe de biomoléculas vitais que estão envolvidos em inúmeros processos e funções que vão desde a ser a moeda universal de energia para os reguladores do metabolismo celular. Em adição ao seu papel nestas transformações biológicas fundamentais, os seus homólogos modificados têm avançado como uma plataforma versátil e leve para a introdução de grupos funcionais em oligonucleótidos, uma metodologia bem que complementa a síntese em fase sólida automatizada, que é normalmente aplicada 1,2. De fato, desde que os (d) PNT pode atuar como substratos para RNA e DNA polimerases 3, uma grande variedade de grupos funcionais, incluindo aminoácidos 4-13, ácidos borónico 14,15, nornbornene 16, resíduos diamantóides-17, como cadeias laterais de organocatálise 18, ácidos biliares, e até 19 oligonucleótidos 20 pode ser introduzido em oligonucleótidos. _content &quot;&gt; Além de representar um vetor conveniente para a funcionalização de ácidos nucleicos, dNTPs modificados podem ser envolvidos em SELEX e outros métodos combinatórios relacionados de seleção in vitro para a geração de ácidos nucleicos catalíticos modificados 21-30 e aptâmeros para diversas aplicações práticas 10, 31-36. As cadeias laterais adicionais que são introduzidos através da polimerização dos dNTP modificados são pensados ​​para aumentar o espaço químico que pode ser explorada durante uma experiência de selecção e completar o arsenal funcional bastante pobre de ácidos nucleicos 37. No entanto, apesar destas características atraentes e os recentes progressos realizados no desenvolvimento de ambos sintéticos e métodos analíticos, universalmente aplicável e os procedimentos de alto rendimento existe para a elaboração de trifosfatos de nucleosídeos modificados 2,38. O objetivo do presente protocolo é o de lançar luz sobre a (às vezes) os procedimentos intrincados líder to a síntese e caracterização bioquímica destes blocos de construção activadas (Figura 1B). Especial ênfase será dada em todos os detalhes sintéticos que muitas vezes são difíceis de encontrar ou estão ausentes nas seções experimentais, mas são ainda fundamentais para a conclusão bem sucedida da via sintética levando ao isolamento de pura (d) PNT (Figura 1).

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	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;">tributylammonium pyrophosphate&#160;</td>
			<td style="width:109px;">Sigma Aldrich</td>
			<td style="width:143px;">P8533</td>
			<td style="width:215px;">Hygroscopic solid, keep under Ar</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;"></td>
			<td style="width:109px;"></td>
			<td style="width:143px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">2-chloro-1,3,2-benzodioxaphosphorin-4-one&#160;</td>
			<td style="width:109px;">Sigma Aldrich</td>
			<td align="right" style="width:143px;">324124</td>
			<td>Moisture sensitive</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;"></td>
			<td style="width:109px;"></td>
			<td style="width:143px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;">Pyridine</td>
			<td style="width:109px;">Sigma Aldrich</td>
			<td align="right" style="width:143px;">82704</td>
			<td>Under molecular sieves</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;"></td>
			<td style="width:109px;"></td>
			<td style="width:143px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;">Dioxane</td>
			<td style="width:109px;">Sigma Aldrich</td>
			<td align="right" style="width:143px;">296309</td>
			<td>Under molecular sieves</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;"></td>
			<td style="width:109px;"></td>
			<td style="width:143px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;">dimethylformamide (DMF)</td>
			<td style="width:109px;">Sigma Aldrich</td>
			<td align="right" style="width:143px;">40248</td>
			<td>Under molecular sieves</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;"></td>
			<td style="width:109px;"></td>
			<td style="width:143px;"></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:333px;">Acetonitrile&#160;</td>
			<td style="width:109px;">Fisher Scientific</td>
			<td style="width:143px;"></td>
			<td>HPLC grade</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;"></td>
			<td style="width:109px;"></td>
			<td style="width:143px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;">Triethylamine</td>
			<td style="width:109px;">Sigma Aldrich</td>
			<td align="right" style="width:143px;">90342</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;"></td>
			<td style="width:109px;"></td>
			<td style="width:143px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;">Tributylamine</td>
			<td style="width:109px;">Sigma Aldrich</td>
			<td align="right" style="width:143px;">90781</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;"></td>
			<td style="width:109px;"></td>
			<td style="width:143px;"></td>
			<td></td>
		</tr>
		<tr height="25">
			<td height="25" style="height:25px;width:333px;">ddH2O</td>
			<td style="width:109px;">Milli-Q</td>
			<td style="width:143px;"></td>
			<td>deionized and purified water, autoclaved in the presence of Diethylpyrocarbonate (DEPC)</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;"></td>
			<td style="width:109px;"></td>
			<td style="width:143px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Diethylpyrocarbonate (DEPC)</td>
			<td style="width:109px;">Sigma Aldrich</td>
			<td align="right" style="width:143px;">159220</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;"></td>
			<td style="width:109px;"></td>
			<td style="width:143px;"></td>
			<td></td>
		</tr>
		<tr height="86">
			<td height="86" style="height:86px;width:333px;">D2O</td>
			<td style="width:109px;">Cambridge Isotope Laboratories, Inc.</td>
			<td style="width:143px;">DLM-4-25</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;"></td>
			<td style="width:109px;"></td>
			<td style="width:143px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;"></td>
			<td style="width:109px;"></td>
			<td style="width:143px;"></td>
			<td></td>
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		<tr height="21">
			<td height="21" style="height:21px;width:333px;">Biochemical reagents</td>
			<td style="width:109px;"></td>
			<td style="width:143px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;"></td>
			<td style="width:109px;"></td>
			<td style="width:143px;"></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:333px;">g-[32P]-ATP</td>
			<td style="width:109px;">Hartmann Analytics</td>
			<td style="width:143px;">FP-301</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;"></td>
			<td style="width:109px;"></td>
			<td style="width:143px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;">Natural dNTPs</td>
			<td style="width:109px;">Promega</td>
			<td style="width:143px;">U1420</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;"></td>
			<td style="width:109px;"></td>
			<td style="width:143px;"></td>
			<td></td>
		</tr>
		<tr height="24">
			<td height="24" style="height:24px;width:333px;">Vent (exo-) DNA polymerase</td>
			<td style="width:109px;">NEB</td>
			<td style="width:143px;">M0257S</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;"></td>
			<td style="width:109px;"></td>
			<td style="width:143px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;">DNA polymerase I, Large (Klenow) Fragment</td>
			<td style="width:109px;">NEB</td>
			<td style="width:143px;">MO210S</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;"></td>
			<td style="width:109px;"></td>
			<td style="width:143px;"></td>
			<td></td>
		</tr>
		<tr height="25">
			<td height="25" style="height:25px;width:333px;">9&#176;Nm DNA polymerase</td>
			<td style="width:109px;">NEB</td>
			<td style="width:143px;">MO260S</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;"></td>
			<td style="width:109px;"></td>
			<td style="width:143px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;">Terminal deoxynucleotidyl Transferase (TdT)</td>
			<td style="width:109px;">Promega</td>
			<td style="width:143px;">M828A</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;"></td>
			<td style="width:109px;"></td>
			<td style="width:143px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;">Pwo DNA polymerase</td>
			<td style="width:109px;">Peqlab</td>
			<td style="width:143px;">01 01 5010</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;"></td>
			<td style="width:109px;"></td>
			<td style="width:143px;"></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:333px;">T4 PNK</td>
			<td style="width:109px;">Thermo Scientific</td>
			<td>EK0032</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;"></td>
			<td style="width:109px;"></td>
			<td style="width:143px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;">Acrylamide/bisacrylamide (19:1, 40%)</td>
			<td style="width:109px;">Serva</td>
			<td align="right" style="width:143px;">10679.01</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;"></td>
			<td style="width:109px;"></td>
			<td style="width:143px;"></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:333px;">Agarose</td>
			<td style="width:109px;">Apollo Scientific</td>
			<td style="width:143px;">BIA1177</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;"></td>
			<td style="width:109px;"></td>
			<td style="width:143px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;">G10 Sephadex</td>
			<td style="width:109px;">Sigma</td>
			<td style="width:143px;">G10120</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;"></td>
			<td style="width:109px;"></td>
			<td style="width:143px;"></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:333px;">Urea</td>
			<td style="width:109px;">Apollo Scientific</td>
			<td style="width:143px;">BIU4110</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;"></td>
			<td style="width:109px;"></td>
			<td style="width:143px;"></td>
			<td></td>
		</tr>
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			<td height="21" style="height:21px;width:333px;">Equipment</td>
			<td style="width:109px;"></td>
			<td style="width:143px;"></td>
			<td></td>
		</tr>
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			<td height="21" style="height:21px;width:333px;"></td>
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			<td style="width:143px;"></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:333px;">Jupiter semi-preparative RP-HPLC column (5m C18 300&#197;)</td>
			<td style="width:109px;">Phenomenex</td>
			<td style="width:143px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;"></td>
			<td style="width:109px;"></td>
			<td style="width:143px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;">Gene Q Thermal Cycler</td>
			<td style="width:109px;">Bioconcept</td>
			<td style="width:143px;">BYQ6042E</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;"></td>
			<td style="width:109px;"></td>
			<td style="width:143px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;">PCR vials</td>
			<td style="width:109px;">Bioconcept</td>
			<td style="width:143px;">3220-00</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;"></td>
			<td style="width:109px;"></td>
			<td style="width:143px;"></td>
			<td></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:333px;">HPLC system</td>
			<td style="width:109px;">Amersham Pharmacia Biotech</td>
			<td style="width:143px;"></td>
			<td>&#196;kta basic 10/100</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;"></td>
			<td style="width:109px;"></td>
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			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;">Oligonucleotides</td>
			<td style="width:109px;"></td>
			<td style="width:143px;"></td>
			<td></td>
		</tr>
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		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:333px;">All oligonucleotides were purchased from Microsynth and purified by PAGE</td>
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			<td></td>
		</tr>
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			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;">5&#39;-CAAGGACAAAATACCTGTATTCCTT P1</td>
			<td style="width:109px;"></td>
			<td style="width:143px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;"></td>
			<td style="width:109px;"></td>
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			<td></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:333px;">5&#39;-GACATCATGAGAGACATCGCCTCTGGGCTAAT-AGGACTACTTCTAATCTGTAAGAGCAGATCCCTGG-ACAGGCAAGGAATACAGGTATTTTGTCCTTG T1</td>
			<td style="width:109px;"></td>
			<td style="width:143px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;"></td>
			<td style="width:109px;"></td>
			<td style="width:143px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;">5&#39;-GAATTCGATATCAAG P2</td>
			<td style="width:109px;"></td>
			<td style="width:143px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;"></td>
			<td style="width:109px;"></td>
			<td style="width:143px;"></td>
			<td></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:333px;">More information on experimental procedures and equipment can be found in the following articles:</td>
			<td style="width:109px;"></td>
			<td style="width:143px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:333px;">Chem. Eur. J. 2012, 18, 13320 &#8211; 13330</td>
			<td style="width:109px;"></td>
			<td style="width:143px;"></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:333px;">Org. Biomol. Chem. 2013, DOI: 10.1039/C3OB40842F.</td>
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			<td></td>
		</tr>
	</tbody>
</table>

nucleoside triphosphates - from synthesis to biochemical characterization

A estratégia tradicional para a introdução de funcionalidades químicas é a utilização de síntese em fase sólida, anexando precursores fosforamideto adequadamente modificados para a cadeia nascente. No entanto, nas condições utilizadas durante a sintese e a restrição de sequências curtas em vez dificultar a aplicabilidade desta metodologia. Por outro lado, trifosfatos de nucleósidos modificados são activados os blocos de construção que têm sido empregues para a introdução suave de numerosos grupos funcionais nos ácidos nucleicos, uma estratégia que abre o caminho para a utilização de ácidos nucleicos modificados numa paleta ampla de aplicações práticas como marcação funcional e geração de ribozimas e DNAzymes. Um dos maiores desafios reside na complexidade da metodologia conduz ao isolamento e caracterização destes análogos de nucleósidos. Neste artigo de vídeo, que apresentam um protocolo detalhado para a síntese de these análogos modificados utilizando reagentes baseados em fósforo (III). Além disso, o procedimento para a sua caracterização bioquímica é divulgada, com uma ênfase especial em reações de extensão de primers e polimerização tailing TdT. Este protocolo detalhado será de uso para a elaboração de dNTPs modificados e seu posterior uso em biologia química.

Trifosfatos de nucleosídeos modificados são atraentes alvos sintéticos, uma vez que permitem a introdução fácil de um vasto leque de grupos funcionais em ácidos nucléicos 41. No entanto, o isolamento e caracterização desses blocos de construção é frequentemente activadas revelaram ser difícil. Consequentemente, os resultados aqui apresentados são pensados ​​para oferecer uma mão amiga para acompanhar as diversas etapas dentro dos procedimentos sintéticos e bioquímicos acima mencionados <...

Watch this Scientific Journal Video about Nucleoside Triphosphates - From Synthesis to Biochemical Characterization at JoVE.com

Nucleoside Triphosphates - From Synthesis to Biochemical Characterization

O protocolo aqui descrito visa explicar e resumir os numerosos obstáculos no caminho da rota intrincada levando a trifosfatos de nucleosídeos modificados. Consequentemente, este protocolo facilita tanto a síntese desses blocos de construção ativados e sua disponibilidade para aplicações práticas.

Nucleosídeos Trisfosfatos - Da síntese à Caracterização Bioquímica

The  traditional strategy for the introduction of chemical functionalities is the  use of solid-phase synthesis by appending suitably modified ...

nucleoside-triphosphates-from-synthesis-to-biochemical

Research

JoVE Journal

Chemistry

17.0K visualizações.  University of Bern.  O protocolo aqui descrito visa explicar e resumir os numerosos obstáculos no caminho da rota intrincada levando a trifosfatos de nucleosídeos modificados. Consequentemente, este protocolo facilita tanto a síntese desses blocos de construção ativados e sua disponibilidade para aplicações práticas. 

Vídeo: Nucleoside Triphosphates - From Synthesis to Biochemical Characterization

Split-and-pool Synthesis and Characterization of Peptide Tertiary Amide Library

Peptidomimetics are great sources of protein ligands. The oligomeric nature of these compounds enables us to access large synthetic libraries on solid phase by using combinatorial chemistry. One of the most well studied classes of peptidomimetics is peptoids. Peptoids are easy to synthesize and have been shown to be proteolysis-resistant and cell-permeable. Over the past decade, many useful protein ligands have been identified through screening of peptoid libraries. However, most of the ligands identified from peptoid libraries do not display high affinity, with rare exceptions. This may be due, in part, to the lack of chiral centers and conformational constraints in peptoid molecules. Recently, we described a new synthetic route to access peptide tertiary amides (PTAs). PTAs are a superfamily of peptidomimetics that include but are not limited to peptides, peptoids and N-methylated peptides. With side chains on both &#945;-carbon and main chain nitrogen atoms, the conformation of these molecules are greatly constrained by sterical hindrance and allylic 1,3 strain. (Figure 1) Our study suggests that these PTA molecules are highly structured in solution and can be used to identify protein ligands. We believe that these molecules can be a future source of high-affinity protein ligands. Here we describe the synthetic method combining the power of both split-and-pool and sub-monomer strategies to synthesize a sample one-bead one-compound (OBOC) library of PTAs.

Peptide tertiary amides (PTAs) are a superfamily of peptidomimetics that include but are not limited to peptides, peptoids and N-methylated peptides. Here we describe a synthetic method which combines&#160;both split-and-pool and sub-monomer strategies to synthesize a one-bead one-compound library of PTAs.

Split-and-piscina Síntese e Caracterização de Peptídeos Terciário Amide Biblioteca

Peptidomimetics are great sources of protein ligands. The oligomeric nature of these compounds enables us to access large synthetic libraries on solid ...

Química

Synthesis and Characterization of Functionalized Metal-organic Frameworks

Metal-organic frameworks have attracted extraordinary amounts of research attention, as they are attractive candidates for numerous industrial and technological applications. Their signature property is their ultrahigh porosity, which however imparts a series of challenges when it comes to both constructing them and working with them. Securing desired MOF chemical and physical functionality by linker/node assembly into a highly porous framework of choice can pose difficulties, as less porous and more thermodynamically stable congeners (e.g., other crystalline polymorphs, catenated analogues) are often preferentially obtained by conventional synthesis methods. Once the desired product is obtained, its characterization often requires specialized techniques that address complications potentially arising from, for example, guest-molecule loss or preferential orientation of microcrystallites. Finally, accessing the large voids inside the MOFs for use in applications that involve gases can be problematic, as frameworks may be subject to collapse during removal of solvent molecules (remnants of solvothermal synthesis). In this paper, we describe synthesis and characterization methods routinely utilized in our lab either to solve or circumvent these issues. The methods include solvent-assisted linker exchange, powder X-ray diffraction in capillaries, and materials activation (cavity evacuation) by supercritical CO2 drying. Finally, we provide a protocol for determining a suitable pressure region for applying the Brunauer-Emmett-Teller analysis to nitrogen isotherms, so as to estimate surface area of MOFs with good accuracy.

Synthesis, activation, and characterization of intentionally designed metal-organic framework materials is challenging, especially when building blocks are incompatible or unwanted polymorphs are thermodynamically favored over desired forms. We describe how applications of solvent-assisted linker exchange, powder X-ray diffraction in capillaries and activation via supercritical CO2 drying, can address some of these challenges.

Síntese e caracterização de funcionalizados metal-organic frameworks

Metal-organic frameworks have attracted extraordinary amounts of research attention, as they are attractive candidates for numerous industrial and ...

The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes

Herein we report the synthesis of a tridentate phosphine ligand N(CH2PPh2)3 (N-triphosPh) (1) via a phosphorus based Mannich reaction of the hydroxylmethylene phosphine precursor with ammonia in methanol under a nitrogen atmosphere. The N-triphosPh ligand precipitates from the solution after approximately 1 hr of reflux and can be isolated analytically pure via simple cannula filtration procedure under nitrogen. Reaction of the N-triphosPh ligand with [Ru3(CO)12] under reflux affords a deep red solution that show evolution of CO gas on ligand complexation. Orange crystals of the complex [Ru(CO)2{N(CH2PPh2)3}-&#954;3P] (2) were isolated on cooling to RT. The 31P{1H} NMR spectrum showed a characteristic single peak at lower frequency compared to the free ligand. Reaction of a toluene solution of complex 2 with oxygen resulted in the instantaneous precipitation of the carbonate complex [Ru(CO3)(CO){N(CH2PPh2)3}-&#954;3P] (3) as an air stable orange solid. Subsequent hydrogenation of 3 under 15 bar of hydrogen in a high-pressure reactor gave the dihydride complex [RuH2(CO){N(CH2PPh2)3}-&#954;3P] (4), which was fully characterized by X-ray crystallography and NMR spectroscopy. Complexes 3 and 4 are potentially useful catalyst precursors for a range of hydrogenation reactions, including biomass-derived products such as levulinic acid (LA). Complex 4 was found to cleanly react with LA in the presence of the proton source additive NH4PF6 to give [Ru(CO){N(CH2PPh2)3}-&#954;3P{CH3CO(CH2)2CO2H}-&#954;2O](PF6) (6).

The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes

Ruthenium phosphine complexes are widely used for homogeneous catalytic reactions such as hydrogenations. The synthesis of a series of novel tridentate ruthenium complexes bearing the N-triphos ligand N(CH2PPh2)3 is reported. Additionally, the stoichiometric reaction of a dihydride Ru&#8211;N-triphos complex with levulinic acid is described.

A Síntese, Caracterização e Reatividade de uma série de Rutênio<em&gt; N</em&gt; -triphos<sup&gt; Ph</sup&gt; Complexos

Herein we report the synthesis of a tridentate phosphine ligand N(CH2PPh2)3 (N-triphosPh) (1) via a phosphorus based Mannich reaction of the ...

Synthesis, Characterization, and Functionalization of Hybrid Au/CdS and Au/ZnS Core/Shell Nanoparticles

Plasmonic nanoparticles are an attractive material for light harvesting applications due to their easily modified surface, high surface area and large extinction coefficients which can be tuned across the visible spectrum. Research into the plasmonic enhancement of optical transitions has become popular, due to the possibility of altering and in some cases improving photo-absorption or emission properties of nearby chromophores such as molecular dyes or quantum dots. The electric field of the plasmon can couple with the excitation dipole of a chromophore, perturbing the electronic states involved in the transition and leading to increased absorption and emission rates. These enhancements can also be negated at close distances by energy transfer mechanism, making the spatial arrangement of the two species critical. Ultimately, enhancement of light harvesting efficiency in plasmonic solar cells could lead to thinner and, therefore, lower cost devices. The development of hybrid core/shell particles could offer a solution to this issue. The addition of a dielectric spacer between a gold nanoparticles and a chromophore is the proposed method to control the exciton plasmon coupling strength and thereby balance losses with the plasmonic gains. A detailed procedure for the coating of gold nanoparticles with CdS and ZnS semiconductor shells is presented. The nanoparticles show high uniformity with size control in both the core gold particles and shell species allowing for a more accurate investigation into the plasmonic enhancement of external chromophores.

The synthesis of uniform gold nanoparticles coated with semiconductor shells of CdS or ZnS is performed. The semiconductor coating is conducted by first depositing a silver sulfide shell and exchanging the silver cations for zinc or cadmium cations.

Síntese, caracterização e funcionalização de híbrida UA / CDS e Au / ZnS Núcleo / Shell Nanopartículas

Plasmonic nanoparticles are an attractive material for light harvesting applications due to their easily modified surface, high surface area and large ...

Synthesis and Characterization of Supramolecular Colloids

Control over colloidal assembly is of utmost importance for the development of functional colloidal materials with tailored structural and mechanical properties for applications in photonics, drug delivery and coating technology. Here we present a new family of colloidal building blocks, coined supramolecular colloids, whose self-assembly is controlled through surface-functionalization with a benzene-1,3,5-tricarboxamide (BTA) derived supramolecular moiety. Such BTAs interact via directional, strong, yet reversible hydrogen-bonds with other identical BTAs. Herein, a protocol is presented that describes how to couple these BTAs to colloids and how to quantify the number of coupling sites, which determines the multivalency of the supramolecular colloids. Light scattering measurements show that the refractive index of the colloids is almost matched with that of the solvent, which strongly reduces the van der Waals forces between the colloids. Before photo-activation, the colloids remain well dispersed, as the BTAs are equipped with a photo-labile group that blocks the formation of hydrogen-bonds. Controlled deprotection with UV-light activates the short-range hydrogen-bonds between the BTAs, which triggers the colloidal self-assembly. The evolution from the dispersed state to the clustered state is monitored by confocal microscopy. These results are further quantified by image analysis with simple routines using ImageJ and Matlab. This merger of supramolecular chemistry and colloidal science offers a direct route towards light- and thermo-responsive colloidal assembly encoded in the surface-grafted monolayer.

A protocol for the synthesis and characterization of colloids coated with supramolecular moieties is described. These supramolecular colloids undergo self-assembly upon the activation of the hydrogen-bonds between the surface-anchored molecules by UV-light.

Síntese e Caracterização de Supramoleculares Colloids

Control over colloidal assembly is of utmost importance for the development of functional colloidal materials with tailored structural and mechanical ...

HPLC-based Assay to Monitor Extracellular Nucleotide/Nucleoside Metabolism in Human Chronic Lymphocytic Leukemia Cells

This method describes a sensitive, specific, reliable and reproducible reverse phase high-performance liquid chromatography (RP-HPLC) assay developed and validated for the quantification of extracellular purine nucleotides and nucleosides produced by purified chronic lymphocytic leukemia (CLL) cells under different culture conditions. The chromatographic separation of adenosine 5&#39;-monophosphate (AMP), adenosine (ADO) and inosine (INO) is performed at RT on a silica-based, reversed-phase column that is used for polar compound retention. The method includes a binary mobile phase, which consists of 7 mM ammonium acetate and acetonitrile with a flow rate of 1.00 ml/min. The eluates are monitored using a Photodiode Array UV detector set at 260 nm. A standard calibration curve is generated to calculate the equation for the analytical quantification of each purine compound. System control, data acquisition and analysis are then performed. Applying this protocol, AMP, INO and ADO elute at 7, 11 and 11.9 min, respectively, and the total run time for each sample is 20 min. This protocol may be applied to different cell types and cell lines (both suspension and adherent), using culture media as matrix. The advantages are easy and fast sample preparation and the requirement of a small amount of supernatant for analysis. Furthermore, the use of a serum-free medium allows skipping the protein precipitation step with acetonitrile that impacts the final concentration of purine compounds. One of the limitations of the method is the requirement of the equilibration column run before each single sample run, making the total run time of the experiment longer and preventing high throughput screening applications.

The protocol described here represents an easy and reproducible method that employs reverse phase high-performance liquid chromatography (RP-HPLC) to measure purine metabolism on chronic lymphocytic leukemia (CLL) cells cultured under different conditions.

-HPLC baseado Ensaio para monitorar Extracelular Nucleotide / nucleosídeos Metabolismo em crônicas células de leucemia linfocítica Humanos

This method describes a sensitive, specific, reliable and reproducible reverse phase high-performance liquid chromatography (RP-HPLC) assay developed and ...

Synthesis and Characterization of Fe-doped Aluminosilicate Nanotubes with Enhanced Electron Conductive Properties

The goal of the protocol is to synthesize Fe-doped aluminosilicate nanotubes of the imogolite type with the formula (OH)3Al2-xFexO3SiOH. Doping with Fe aims at lowering the band gap of imogolite, an insulator with the chemical formula (OH)3Al2O3SiOH, and at modifying its adsorption properties towards azo-dyes, an important class of organic pollutants of both wastewater and groundwater.
Fe-doped nanotubes are obtained in two ways: by direct synthesis, where FeCl3 is added to an aqueous mixture of the Si and Al precursors, and by post-synthesis loading, where preformed nanotubes are put in contact with a FeCl3&#8226;6H2O aqueous solution. In both synthesis methods, isomorphic substitution of Al3+ by Fe3+ occurs, preserving the nanotube structure. Isomorphic substitution is indeed limited to a mass fraction of ~1.0% Fe, since at a higher Fe content (i.e., a mass fraction of 1.4% Fe), Fe2O3 clusters form, especially when the loading procedure is adopted. The physicochemical properties of the materials are studied by means of X-ray powder diffraction (XRD), N2 sorption isotherms at -196 &#176;C, high resolution transmission electron microscopy (HRTEM), diffuse reflectance (DR) UV-Vis spectroscopy, and &#950;-potential measurements. The most relevant result is the possibility to replace Al3+ ions (located on the outer surface of the nanotubes) by post-synthesis loading on preformed imogolite without perturbing the delicate hydrolysis equilibria occurring during nanotube formation. During the loading procedure, an anionic exchange occurs, where Al3+ ions on the outer surface of the nanotubes are replaced by Fe3+ ions. In Fe-doped aluminosilicate nanotubes, isomorphic substitution of Al3+ by Fe3+ is found to affect the band gap of doped imogolite. Nonetheless, Fe3+ sites on the outer surface of nanotubes are able to coordinate organic moieties, like the azo-dye Acid Orange 7, through a ligand-displacement mechanism occurring in an aqueous solution.

Here, we present a protocol to synthesize and characterize Fe-doped aluminosilicate nanotubes. The materials are obtained by either sol-gel synthesis upon addition of FeCl3&#8226;6H2O to the mixture containing the Si and Al precursors or by post-synthesis ionic exchange of preformed aluminosilicate nanotubes.

Síntese e Caracterização de Fe-dopado alumino nanotubos com propriedades condutoras aprimorados Electron

The goal of the protocol is to synthesize Fe-doped aluminosilicate nanotubes of the imogolite type with the formula (OH)3Al2-xFexO3SiOH. Doping with Fe ...

Enzymatic Cascade Reactions for the Synthesis of Chiral Amino Alcohols from L-lysine

Amino alcohols are versatile compounds with a wide range of applications. For instance, they have been used as chiral scaffolds in organic synthesis. Their synthesis by conventional organic chemistry often requires tedious multi-step synthesis processes, with difficult control of the stereochemical outcome. We present a protocol to enzymatically synthetize amino alcohols starting from the readily available L-lysine in 48 h. This protocol combines two chemical reactions that are very difficult to conduct by conventional organic synthesis. In the first step, the regio- and diastereoselective oxidation of an unactivated C-H bond of the lysine side-chain is catalyzed by a dioxygenase; a second regio- and diastereoselective oxidation catalyzed by a regiodivergent dioxygenase can lead to the formation of the 1,2-diols. In the last step, the carboxylic group of the alpha amino acid is cleaved by a pyridoxal-phosphate (PLP) decarboxylase (DC). This decarboxylative step only affects the alpha carbon of the amino acid, retaining the hydroxy-substituted stereogenic center in a beta/gamma position. The resulting amino alcohols are therefore optically enriched. The protocol was successfully applied to the semipreparative-scale synthesis of four amino alcohols. Monitoring of the reactions was conducted by high performance liquid chromatography (HPLC) after derivatization by 1-fluoro-2,4-dinitrobenzene. Straightforward purification by solid-phase extraction (SPE) afforded the amino alcohols with excellent yields (93% to &#62;95%).

Chiral amino alcohols are versatile molecules for use as scaffolds in organic synthesis. Starting from L-lysine, we synthesize amino alcohols by an enzymatic cascade reaction combining diastereoselective C-H oxidation catalyzed by dioxygenase followed by cleavage of the carboxylic acid moiety of the corresponding hydroxyl amino acid by a decarboxylase.

Reações Enzimáticas em Cascata para a Síntese de Aminoálcoois Quirais a partir de L-lisina

Amino alcohols are versatile compounds with a wide range of applications. For instance, they have been used as chiral scaffolds in organic synthesis. ...

Synthesis and Characterization of 1,2-Dithiolane Modified Self-Assembling Peptides

This report focuses on the synthesis of an N-terminus 1,2-dithiolane modified self-assembling peptide and the characterization of the resulting self-assembled supramolecular structures. The synthetic route takes advantage of solid-phase peptide synthesis with the on-resin coupling of the dithiolane precursor molecule, 3-(acetylthio)-2-(acetylthiomethyl)propanoic acid, and the microwave-assisted thioacetate deprotection of the peptide N-terminus before final cleavage from the resin to yield the 1,2-dithiolane modified peptide. After the high-performance liquid chromatography (HPLC) purification of the 1,2-dithiolane peptide, derived from the nucleating core of the A&#946; peptide associated with Alzheimer&#39;s disease, the peptide is shown to self-assemble into cross-&#946; amyloid fibers. Protocols to characterize the amyloid fibers by Fourier-transform infrared spectroscopy (FT-IR), circular dichroism spectroscopy (CD) and transmission electron microscopy (TEM) are presented. The methods of N-terminal modification with a 1,2-dithiolane moiety to well-characterized self-assembling peptides can now be explored as model systems to develop post-assembly modification strategies and explore dynamic covalent chemistry on supramolecular peptide nanofiber surfaces.

A protocol for the synthesis of a 1,2-dithiolane modified peptide and the characterization of the supramolecular structures resulting from the peptide self-assembly.

Síntese e caracterização de 1,2-Ditiolano modificado peptídeos auto-montagem

This report focuses on the synthesis of an N-terminus 1,2-dithiolane modified self-assembling peptide and the characterization of the resulting ...

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.

Síntese e caracterização de nanopartículas de ouro Anfífilos

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