The authors acknowledge National Science Foundation grant CHE- 1214068 for supporting this research project.

1.准备大湄公河次区域<ol><li>使用所有的化学品，在以下的处理作为接收。 </li><li>制备75毫升的盐酸（HCl）溶液的2M。权衡将2.0g聚（乙二醇） - 嵌段 - 聚（丙二醇） - 嵌段 - 聚（乙二醇）（P123，MW = 5800），并转移到制备75的2M盐酸溶液。在RT，应用磁力搅拌的溶液在350转/分的速度，直至P123完全溶解。该解决方案将是明确的。 </li><li>权衡4克四乙氧基硅烷（TEOS，MW = 208.33）在一个小瓶和转让180微升双[3-（三乙氧基甲硅烷基）丙基] - 四硫化物（TESPTS，MW = 538.94）到小瓶。慢摇瓶中混合使用这两种化学物质。在另一个小瓶中，称取38毫克氯金酸的（氯金酸4，99.90％）和溶解在1ml去离子水中。 </li><li>增加的P123溶​​液温度至35℃的油浴温度由热电偶控制。 </li><li>添加所有加入的TEOS的混合物和在步骤1.3至P123溶​​液制备TESPTS，并保持溶液在700转/分钟剧烈磁力搅拌。保持该溶液搅拌2分钟，然后加入所有的在30秒内制备，在步骤1.3滴加氯金酸4溶液。 </li><li>保持溶液在700转/分在35℃下搅拌24小时。 </li><li> 24小时后，转移在一个烘箱中在100℃下进行72小时的溶液到一个密封的瓶子，并存储。这就是所谓的水热加工。 </li><li>热液处理后，进行过滤以＃1过滤纸和负压下的溶液的漏斗，然后用水洗涤两次，乙醇三次，以除去剩余的HCl。在每次洗涤过程中，加水或乙醇上方1厘米的固体，并等待该材料干燥。 </li><li>从过滤转移沉淀到陶瓷坩埚中并煅烧在550℃进行4小时。设置斜坡程序如下：25℃〜550℃进行2小时，保持在550℃下进行4小时，然后使样品保留在炉中的门关闭，直到温度下降到低于40℃。 </li><li>煅烧后，将产物用塑料刮铲转移至玻璃小瓶中。合成材料具有红色。 </li></ol> 2.催化反应，苯甲醇的氧化<ol><li>自苄醇的氧化是没有单独的溶剂的液相反应，测量5毫升苄醇（99.8％），并将其转移到25毫升三颈烧瓶中，然后称重10毫克GMS催化剂并将其添加到苯酒精。 </li><li>设置了温度控制的油浴中磁搅拌，以保证反应温度精确和均匀的控制。 </li><li>放与苄醇及催化剂的烧瓶放入油浴中，然后将温度设置为100℃，搅拌，在150转/分。 </li><li>流动氧气与99.9％纯度到烧瓶中以2毫升/分钟通过一个质量流量控制器控制。 </li><li>当...的时候将油浴温度达到100℃并稳定时，引入的氧气进入三颈烧瓶中。 </li><li>保持氧气流率和温度恒定，并允许反应进行6小时。 </li><li>反应后，过滤该产物与＃1过滤纸。收集液相和等分试样转移到气相色谱（GC）小瓶中。在GC小瓶中，混合四部分HPLC级乙酸，每一个部分样品（例如，使用36微升样品和144微升乙酸。）将小瓶上气相色谱自动取样用于分析。上用DI水和乙醇在滤纸洗掉固体沉淀物，然后允许在空气中干燥。收集干燥的固体用刮铲作为再循环催化剂。 </li><li>通过2.7使用回收的催化剂三次重复步骤2.3相同的实验过程。在每个重复，调整苄醇的量，以在步骤2.2中所述的比率匹配。 </li></ol> 3.疗法大湄公河次区域的发作治疗热稳定性的测试<ol><li>权衡合成GMS三个独立300mg的部分，并且将它们存储在玻璃小瓶中。这些被标记为1批，第2批和批3.保持1批为对照组，并把第2批和第3批入炉热加工。 </li><li>程序作为在400℃以下进行处理炉：在0.5小时斜坡从25℃至400℃，在400℃下保持4小时，使样品保持与门的炉关闭，直到温度瀑布低于40℃。把第2批中的坩埚，并启动该程序。 </li><li>程序作为在650℃以下进行处理炉：在0.75小时斜坡从25℃至650℃，在650℃下保持4小时，使样品保留在炉中门关闭，直到下面的温度下降40℃。把批3中的坩埚，并启动该程序。 </li></ol> 4.表征GMS材料21,22 <ol><li>上的物理吸附仪器，脱气GMS材料与以下程序：90℃60分钟，然后350℃，480分钟。运行在脱气材料全等温线的分析来获得物理吸附数据。 </li><li>分散GMS样品上200目多孔碳TEM网格并观察透射型电子显微镜下的样品。限制44,000X放大倍率下，以保护材料。 </li><li>运行的XRD用CuKα射线（λ= 1.5418）。集管电压为45kV，和40毫安管电流。收集强度在2θ范围在10°和90°与0.008°的步长和5秒的每一步的测量时间。 </li></ol>

<ol>
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The authors have nothing to disclose.

内的合成方案，关注的表面活性剂的浓度，pH值的溶液中，反应温度是在成功形成GMS是至关重要的。关键步骤是1.2，1.3，1.4和1.6。上述参数控制从表面活性剂形成的胶束的临界堆积参数和相位。胶束的相位和形态确定二氧化硅基质，将成为用于GMS框架的最终状态。另外，在形成过程中重要的是该序列和时间添加氯金酸溶液。 TEOS和TESPTS分别作为二氧化硅源和表面改性剂。加入两种化学物质首先确保...

作为一项新兴技术，在催化领域的应用潜力巨大，纳米材料已收到深入研究的兴趣在过去几十年。当中的纳米级催化剂报道，贵金属催化剂，如金，银，钯和铂吸引了世界的广泛关注1-3。选择催化反应包括一氧化碳研究者氧化的金，赫克在Pd催化剂的反应，并与铂分解水。尽管有为催化潜力，纳米级金在其适用性由于从中毒，焦化，热降解，和烧结失活限制。已经报道了金，作为贵金属的代表，具有高的选择性和不易于金属浸出，过度氧化和自中毒4。然而，金的催化性能强烈地依赖于颗粒尺寸。春田等人已报告的催化性能与去之间的关系ld的团簇直径，这表明金催化剂的活性最高粒度〜2.7毫微米5。 贵金属的粒径，可以通过在制备方法6-9进行控制;然而，走向广阔的应用的主要障碍仍然聚集而失去活性。为了解决烧结的问题，通常的方法是将固定纳米级颗粒在载体材料上。各种辅助材料已应用于包括多孔二氧化硅10-11，半导体金属氧化物12-13，聚合物14，石墨烯15和碳纳米管16。之间所使用的材料，多孔硅石是一个有吸引力的材料作为支持，因为它是唯一的弱酸性，相对惰性的，热和化学稳定的，并且能以非常明确的内消旋/微孔隙率来制备。多孔结构提供了良好的支持金属颗粒，但也赋予的大小选择衬底通道的金属催化剂。这种选择性是因为与这些多孔材料有关的可调谐性的特别有前途的。通常情况下，金颗粒被发现是在硅胶上表面17-18极其移动和容易地当暴露于高温时形成非常大的（50 + nm）的反应性的颗粒，从而使得难以制备金纳米颗粒在二氧化硅上19。 Mukherjee 等。的单分散金纳米粒子上的介孔二氧化硅的MCM-41由3-氨基丙基-三甲氧基硅烷和3-巯基丙基-三乙氧基硅烷，以及支持的金纳米颗粒报道固定化被认为是用于氢化反应的高活性和无浸出的金被发现在反应20。 下面介孔二氧化硅的表面改性的报告中，我们报道了法制备金嵌入到介孔二氧化硅（GMS）的墙。此外，介孔二氧化硅支持的方法提供了一个可扩展的APproach潜在独立地改变催化剂和多孔环境。由于催化过程是重要的经济意义，带来的好处可能是深远的。开发能力的“绿色”催化剂会对环境产生深远的积极影响和改善重要的工业过程的经济可行性和资源利用效率。

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr>
			<td>poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol)</td>
			<td>Aldrich</td>
			<td>435465-250ML</td>
			<td></td>
		</tr>
		<tr>
			<td>tetraethoxysilane</td>
			<td>TCI</td>
			<td>201-083-8</td>
			<td></td>
		</tr>
		<tr>
			<td>bis[3-(triethoxysilyl)propyl]-tetrasulfide</td>
			<td>GELEST</td>
			<td>SIB1825.0-100GM</td>
			<td></td>
		</tr>
		<tr>
			<td>chloroauric acid</td>
			<td>Aldrich</td>
			<td>520918-1G</td>
			<td></td>
		</tr>
		<tr>
			<td>benzyl alcohol</td>
			<td>Sigma-Aldrich</td>
			<td>305197-1L</td>
			<td></td>
		</tr>
		<tr>
			<td>nitrogen physisorption</td>
			<td>Micromeritics</td>
			<td>Tristar II</td>
			<td></td>
		</tr>
		<tr>
			<td>X-ray diffraction</td>
			<td>Philips</td>
			<td>X&#39;Pert Pro</td>
			<td></td>
		</tr>
		<tr>
			<td>transmission electron microscopy</td>
			<td>Philips</td>
			<td>CM200</td>
			<td></td>
		</tr>
		<tr>
			<td>gas chromatography</td>
			<td>Shimadzu</td>
			<td>GC-2010</td>
			<td></td>
		</tr>
	</tbody>
</table>

synthesis and catalytic performance of gold intercalated in the walls of mesoporous silica

作为有希望的催化活性纳米反应器，在介孔二氧化硅（GMS）的插层纳米金成功地合成和材料的性能进行了研究。我们使用了一锅溶胶 - 凝胶方法来插层中孔二氧化硅的壁金纳米颗粒。开始与合成，P123用作模板以形成胶束。然后TESPTS用作表面改性剂插层金纳米颗粒。按照此过程，TEOS加入在作为经历聚合过程在酸性环境中的二氧化硅源。热液处理和煅烧后，获得的最终产品。几种技术被用于表征金插孔二氧化硅的孔隙率，形态和结构。结果表明金插后的介孔二氧化硅的稳定的结构。通过苄醇的氧化为基准的反应，所述GMS材料表现出高选择素拉了一和可回收性。

该方法是用来比较在正常（HBEC30KT）血红素合成的水平与癌（HCC4017）肺细胞。 图2示出了血红素合成中的癌细胞（HCC4017）比正常肺细胞（HBEC30KT）的更高的水平。血红素合成的水平，也测量在正常细胞和癌细胞中的线粒体解偶联剂羰氰-3-氯苯（CCCP）的存在。用10微米的CCCP的血红素合成水平测量之前处理细胞24小时。正如所料，血红素合成的水平（ 图2）中的CCCP的在正常和?...

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Synthesis and Catalytic Performance of Gold Intercalated in the Walls of Mesoporous Silica

Here, we present a protocol with a sol-gel process to synthesize gold intercalated in the walls of mesoporous materials (GMS), which is confirmed to possess a mesoporous matrix with gold intercalated in the walls imparting great stability and recyclability.

合成和金插在介孔二氧化硅的墙壁催化性能

As a promising catalytically active nano reactor, gold nanoparticles intercalated in mesoporous silica (GMS) were successfully synthesized and properties ...

synthesis-catalytic-performance-gold-intercalated-walls-mesoporous

Research

JoVE Journal

Chemistry

9.9K 次观看.  Colorado School of Mines. Here, we present a protocol with a sol-gel process to synthesize gold intercalated in the walls of mesoporous materials (GMS), which is confirmed to possess a mesoporous matrix with gold intercalated in the walls imparting great stability and recyclability.

视频: Synthesis and Catalytic Performance of Gold Intercalated in the Walls of Mesoporous Silica

Isolation and Preparation of Bacterial Cell Walls for Compositional Analysis by Ultra Performance Liquid Chromatography

The bacterial cell wall is critical for the determination of cell shape during growth and division, and maintains the mechanical integrity of cells in the face of turgor pressures several atmospheres in magnitude. Across the diverse shapes and sizes of the bacterial kingdom, the cell wall is composed of peptidoglycan, a macromolecular network of sugar strands crosslinked by short peptides. Peptidoglycan&#8217;s central importance to bacterial physiology underlies its use as an antibiotic target and has motivated genetic, structural, and cell biological studies of how it is robustly assembled during growth and division. Nonetheless, extensive investigations are still required to fully characterize the key enzymatic activities in peptidoglycan synthesis and the chemical composition of bacterial cell walls. High Performance Liquid Chromatography (HPLC) is a powerful analytical method for quantifying differences in the chemical composition of the walls of bacteria grown under a variety of environmental and genetic conditions, but its throughput is often limited. Here, we present a straightforward procedure for the isolation and preparation of bacterial cell walls for biological analyses of peptidoglycan via HPLC and Ultra Performance Liquid Chromatography (UPLC), an extension of HPLC that utilizes pumps to deliver ultra-high pressures of up to 15,000 psi, compared with 6,000 psi for HPLC. In combination with the preparation of bacterial cell walls presented here, the low-volume sample injectors, detectors with high sampling rates, smaller sample volumes, and shorter run times of UPLC will enable high resolution and throughput for novel discoveries of peptidoglycan composition and fundamental bacterial cell biology in most biological laboratories with access to an ultracentrifuge and UPLC.

The bacterial cell wall is composed of peptidoglycan, a macromolecular network of sugar strands crosslinked by peptides. Ultra Performance Liquid Chromatography provides high resolution and throughput for novel discoveries of peptidoglycan composition. We present a procedure for the isolation of cell walls (sacculi) and their subsequent preparation for analysis via UPLC.

通过超性能液相色谱对细菌细胞壁进行隔离和制备，进行组成分析

The bacterial cell wall is critical for the determination of cell shape during growth and division, and maintains the mechanical integrity of cells in the ...

科研

化学

Sequencing of Plant Wall Heteroxylans Using Enzymic, Chemical (Methylation) and Physical (Mass Spectrometry, Nuclear Magnetic Resonance) Techniques

This protocol describes the specific techniques used for the characterization of reducing end (RE) and internal region glycosyl sequence(s) of heteroxylans. De-starched wheat endosperm cell walls were isolated as an alcohol-insoluble residue (AIR)1 and sequentially extracted with water (W-sol Fr) and 1 M KOH containing 1% NaBH4 (KOH-sol Fr) as described by Ratnayake et al. (2014)2. Two different approaches (see summary in Figure 1) are adopted. In the first, intact W-sol AXs are treated with 2AB to tag the original RE backbone chain sugar residue and then treated with an endoxylanase to generate a mixture of 2AB-labelled RE and internal region reducing oligosaccharides, respectively. In a second approach, the KOH-sol Fr is hydrolyzed with endoxylanase to first generate a mixture of oligosaccharides which are subsequently labelled with 2AB. The enzymically released ((un)tagged) oligosaccharides from both W- and KOH-sol Frs are then methylated and the detailed structural analysis of both the native and methylated oligosaccharides is performed using a combination of MALDI-TOF-MS, RP-HPLC-ESI-QTOF-MS and ESI-MSn. Endoxylanase digested KOH-sol AXs are also characterized by nuclear magnetic resonance (NMR) that also provides information on the anomeric configuration. These techniques can be applied to other classes of polysaccharides using the appropriate endo-hydrolases.

Sequencing of Plant Wall Heteroxylans Using Enzymic, Chemical Methylation and Physical Mass Spectrometry, Nuclear Magnetic Resonance Techniques

This protocol describes the specific techniques used for the structural characterization of reducing end (RE) and internal region glycosyl sequence(s) of heteroxylans by tagging the RE with 2 aminobenzamide prior to enzymatic (endoxylanase) hydrolysis and then analysis of the resultant oligosaccharides using mass spectrometry (MS) and nuclear magnetic resonance (NMR).

使用酶法，化学（甲基化）和物理（质谱，核磁共振）技术，植物墙Heteroxylans测序

This protocol describes the specific techniques used for the characterization of reducing end (RE) and internal region glycosyl sequence(s) of ...

Synthesis of Protein Bioconjugates via Cysteine-maleimide Chemistry

The chemical linking or bioconjugation of proteins to fluorescent dyes, drugs, polymers and other proteins has a broad range of applications, such as the development of antibody drug conjugates (ADCs) and nanomedicine, fluorescent microscopy and systems chemistry. For many of these applications, specificity of the bioconjugation method used is of prime concern. The Michael addition of maleimides with cysteine(s) on the target proteins is highly selective and proceeds rapidly under mild conditions, making it one of the most popular methods for protein bioconjugation.
We demonstrate here the modification of the only surface-accessible cysteine residue on yeast cytochrome c with a ruthenium(II) bisterpyridine maleimide. The protein bioconjugation is verified by gel electrophoresis and purified by aqueous-based fast protein liquid chromatography in 27% yield of isolated protein material. Structural characterization with MALDI-TOF MS and UV-Vis is then used to verify that the bioconjugation is successful. The protocol shown here is easily applicable to other cysteine - maleimide coupling of proteins to other proteins, dyes, drugs or polymers.

Synthesis of Protein Bioconjugates via Cysteine-maleimide Chemistry

This protocol details the important steps required for the bioconjugation of a cysteine containing protein to a maleimide, including reagent purification, reaction conditions, bioconjugate purification and bioconjugate characterization.

蛋白质生物缀合物的合成<em&gt;通过</em&gt;半胱氨酸马来酰亚胺化学

The chemical linking or bioconjugation of proteins to fluorescent dyes, drugs, polymers and other proteins has a broad range of applications, such as the ...

Hydroquinone Based Synthesis of Gold Nanorods

Gold nanorods are an important kind of nanoparticles characterized by peculiar plasmonic properties. Despite their widespread use in nanotechnology, the synthetic methods for the preparation of gold nanorods are still not fully optimized. In this paper we describe a new, highly efficient, two-step protocol based on the use of hydroquinone as a mild reducing agent. Our approach allows the preparation of nanorods with a good control of size and aspect ratio (AR) simply by varying the amount of hexadecyl trimethylammonium bromide (CTAB) and silver ions (Ag+) present in the "growth solution". By using this method, it is possible to markedly reduce the amount of CTAB, an expensive and cytotoxic reagent, necessary to obtain the elongated shape. Gold nanorods with an aspect ratio of about 3 can be obtained in the presence of just 50 mM of CTAB (versus 100 mM used in the standard protocol based on the use of ascorbic acid), while shorter gold nanorods are obtained using a concentration as low as 10 mM.

This paper describes a protocol for the synthesis of gold nanorods, based on the use of hydroquinone as reducing agent, plus the different mechanisms for controlling their size and aspect ratio.

金纳米棒基于对苯二酚合成

Gold nanorods are an important kind of nanoparticles characterized by peculiar plasmonic properties. Despite their widespread use in nanotechnology, the ...

Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions

Detailed and generalized protocols are presented for the synthesis and subsequent purification of four palladium N-heterocyclic carbene complexes from benzimidazolium salts. Detailed and generalized protocols are also presented for testing the catalytic activity of such complexes in arylation and Suzuki-Miyaura cross-coupling reactions. Representative results are shown for the catalytic activity of the four complexes in arylation and Suzuki-Miyaura type reactions. For each of the reactions investigated, at least one of the four complexes successfully catalyzed the reaction, qualifying them as promising candidates for catalysis of many carbon-carbon bond-forming reactions. The protocols presented are general enough to be adapted for the synthesis, purification and catalytic activity testing of new palladium N-heterocyclic carbene complexes.

Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions

Detailed and generalized protocols are presented for the synthesis and subsequent purification of four palladium N-heterocyclic carbene complexes from benzimidazolium salts. The complexes were tested for catalytic activity in arylation and Suzuki-Miyaura reactions. For each reaction investigated, at least one of the four complexes successfully catalyzed the reaction.

钯<em&gt;ñ</em&gt; - 杂环碳烯配合物：苯并咪唑盐的合成和碳 - 碳键合反应中的催化活性

Detailed and generalized protocols are presented for the synthesis and subsequent purification of four palladium N-heterocyclic carbene complexes from ...

Synthesis of Platinum-nickel Nanowires and Optimization for Oxygen Reduction Performance

Platinum-nickel (Pt-Ni) nanowires were developed as fuel cell electrocatalysts, and were optimized for the performance and durability in the oxygen reduction reaction. Spontaneous galvanic displacement was used to deposit Pt layers onto Ni nanowire substrates. The synthesis approach produced catalysts with high specific activities and high Pt surface areas. Hydrogen annealing improved Pt and Ni mixing and specific activity. Acid leaching was used to preferentially remove Ni near the nanowire surface, and oxygen annealing was used to stabilize near-surface Ni, improving durability and minimizing Ni dissolution. These protocols detail the optimization of each post-synthesis processing step, including hydrogen annealing to 250 &#176;C, exposure to 0.1 M nitric acid, and oxygen annealing to 175 &#176;C. Through these steps, Pt-Ni nanowires produced increased activities more than an order of magnitude than Pt nanoparticles, while offering significant durability improvements. The presented protocols are based on Pt-Ni systems in the development of fuel cell catalysts. These techniques have also been used for a variety of metal combinations, and can be applied to develop catalysts for a number of electrochemical processes.

&#160; The protocol describes the synthesis and electrochemical testing of platinum-nickel nanowires. Nanowires were synthesized by the galvanic displacement of a nickel nanowire template. Post-synthesis processing, including hydrogen annealing, acid leaching, and oxygen annealing were used to optimize nanowire performance and durability in the oxygen reduction reaction.

铂镍纳米线的合成及减氧性能优化

Platinum-nickel (Pt-Ni) nanowires were developed as fuel cell electrocatalysts, and were optimized for the performance and durability in the oxygen ...

Chemical Precipitation Method for the Synthesis of Nb2O5 Modified Bulk Nickel Catalysts with High Specific Surface Area

We demonstrate a method for the synthesis of NixNb1-xO catalysts with sponge-like and fold-like nanostructures. By varying the Nb:Ni ratio, a series of NixNb1-xO nanoparticles with different atomic compositions (x = 0.03, 0.08, 0.15, and 0.20) have been prepared by chemical precipitation. These NixNb1-xO catalysts are characterized by X-ray diffraction, X-ray photoelectron spectroscopy, and scanning electron microscopy. The study revealed the sponge-like and fold-like appearance of Ni0.97Nb0.03O and Ni0.92Nb0.08O on the NiO surface, and the larger surface area of these NixNb1-xO catalysts, compared with the bulk NiO. Maximum surface area of 173 m2/g can be obtained for Ni0.92Nb0.08O catalysts. In addition, the catalytic hydroconversion of lignin-derived compounds using the synthesized Ni0.92Nb0.08O catalysts have been investigated.

Chemical Precipitation Method for the Synthesis of Nb2O5 Modified Bulk Nickel Catalysts with High Specific Surface Area

A protocol for the synthesis of sponge-like and fold-like Ni1-xNbxO nanoparticles by chemical precipitation is presented.

化学沉淀法合成铌2O5改性高比表面积镍催化剂

We demonstrate a method for the synthesis of NixNb1-xO catalysts with sponge-like and fold-like nanostructures. By varying the Nb:Ni ratio, a series of ...

Rapid Nanoprobe Signal Enhancement by In Situ Gold Nanoparticle Synthesis

The use of nanoprobes such as gold, silver, silica or iron-oxide nanoparticles as detection reagents in bioanalytical assays can enable high sensitivity and convenient colorimetric readout. However, high densities of nanoparticles are typically needed for detection. The available synthesis-based enhancement protocols are either limited to gold and silver nanoparticles or rely on precise enzymatic control and optimization. Here, we present a protocol to enhance the colorimetric readout of gold, silver, silica, and iron oxide nanoprobes. It was observed that the colorimetric signal can be improved by up to a 10000-fold factor. The basis for such signal enhancement strategies is the chemical reduction of Au3+ to Au0. There are several chemical reactions that enable the reduction of Au3+ to Au0. In the protocol, Good&#39;s buffers and H2O2 are used and it is possible to favor the deposition of Au0 onto the surface of existing nanoprobes, in detriment of the formation of new gold nanoparticles. The protocol consists of the incubation of the microarray with a solution consisting of chloroauric acid and H2O2 in 2-(N-morpholino)ethanesulfonic acid pH 6 buffer following the nanoprobe-based detection assay. The enhancement solution can be applied to paper and glass-based sensors. Moreover, it can be used in commercially available immunoassays as demonstrated by the application of the method to a commercial allergen microarray. The signal development requires less than 5 min of incubation with the enhancement solution and the readout can be assessed by naked eye or low-end image acquisition devices such as a table-top scanner or a digital camera.

Rapid Nanoprobe Signal Enhancement by In Situ Gold Nanoparticle Synthesis

In this work, a protocol for signal enhancement of nanoprobe-based biosensing is presented. The protocol is based on the reduction of chloroauric acid onto the surface of existing nanoprobes that consist of gold, silver, silica or iron-oxide nanoparticles.

原位金纳米粒子合成快速 Nanoprobe 信号增强

The use of nanoprobes such as gold, silver, silica or iron-oxide nanoparticles as detection reagents in bioanalytical assays can enable high sensitivity ...

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.

两栖金纳米粒子的合成与表征

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

Gold Nanoparticle Synthesis

Gold nanoparticles (Au nanoparticles) that are ~12 nm in diameter were synthesized by rapidly injecting a solution of 150 mg (0.15 mmol) of tetrachloroauric acid in 3.0 g (3.7 mmol, 3.6 mL) of oleylamine (technical grade) and 3.0 mL of toluene into a boiling solution of 5.1 g (6.4 mmol, 8.7 mL) of oleylamine in 147 mL of toluene. While boiling and mixing the reaction solution for 2 hours, the color of the reaction mixture changed from clear, to light yellow, to light pink, and then slowly to dark red. The heat was then turned off, and the solution was allowed to gradually cool down to room temperature for 1 hour. The gold nanoparticles were then collected and separated from the solution using a centrifuge and washed three times; by vortexing and dispersing the gold nanoparticles in 10 mL portions of toluene, and then precipitating the gold nanoparticles by adding 40 mL portions of methanol and spinning them in a centrifuge. The solution was then decanted to remove any remaining byproducts and unreacted starting materials. Drying the gold nanoparticles in a vacuum environment produced a solid black pellet; which could be stored for long periods of time (up to one year) for later use, and then redissolved in organic solvents such as toluene.

A protocol for synthesizing ~12 nm diameter gold nanoparticles (Au nanoparticles) in an organic solvent is presented. The gold nanoparticles are capped with oleylamine ligands to prevent agglomeration. The gold nanoparticles are soluble in organic solvents such as toluene.