Funding for this research was provided by the Italian Ministry of Health under the frame of EuroNanoMed II (European Innovative Research &amp; Technological Development Projects in Nanomedicine, project title: ''InNaSERSS'').

1.黄金纳米棒注:在使用高纯水。 <ol><li> 金种子的制备 <ol><li>在40℃于5毫升水中溶解364.4毫克十六烷基溴化铵（CTAB）的，下超声直至形成澄清溶液。让CTAB溶液冷却至室温。 </li><li>另外，在水（0.5毫米）准备5毫升四氯金酸（氯金酸4）。 </li><li>添加氯金酸4溶液向CTAB溶液剧烈磁力搅拌下，保持在27℃的温度恒定。 </li><li>制备硼氢化钠600微升（加入NaBH 4）在4℃的水（10毫摩尔）溶液中。添加该解决方案剧烈搅拌下混合物。检查解决方案的颜色立即从黄色变为褐色。 </li><li>搅拌使用前20分钟的停牌。存储的种子悬浮液在室温彩画不超过24小时TURE。 </li><li>检查种子使用紫外可见分光光度计的尺寸。确保种子是足够小（约2nm）的紫外可见光谱的制备金纳米棒的情况下使用。 注意:频谱必须相似的是，在图1中报道的周围505-520纳米的电浆峰的存在鉴别更大的种子不能使用，因为他们很可能会产生球形纳米颗粒。 </li></ol></li><li> 金纳米棒的" 增长解决方案 "的制备。 <ol><li>连同在5毫升水中22毫克氢醌，在40℃用超声波溶解182.2毫克的CTAB。降温的解决方案，以27°C。 </li><li>制备200μl的4mM的硝酸银（ 硝酸银）溶液。 </li><li>另外，准备溶于5ml四氯金酸的1 mM的溶液（ 氯金酸）。 </li><li>首先添加步骤1.2.2准备的硝酸银溶液。然后，添加HAuCL 4溶液在步骤1.2.3至在步骤1.2.1磁力搅拌下制备的CTAB和氢醌的溶液制备。 </li><li>紧接着，加入磁力搅拌12微升预先根据方案制备的种子悬浮液的报告在步骤1.1下，让反应开始。检查，如果悬浮液在约30分钟改变颜色。 </li><li>通过检查悬浮液的紫外可见光谱，如在第4节，每5分钟控制纳米棒的形成。继续进行，直到光谱是稳定的。以允许纳米棒的完全形成，离开再搅拌30分钟（ 图2）下的悬浮液中。 </li><li>划分在管中的悬浮液（1 ml悬液每个管）和离心机以10,000 xg离心10分钟。金纳米棒形成在管的底部有一个暗沉淀。 </li><li>悬浮每个管的沉淀物在1毫升水中。混合在一起的管子的内容并存储到SUSP在室温下金纳米棒的ension。 </li><li>如在第4（ 图3）描述的紫外-可见光谱和透射电子显微镜表征所获得的纳米棒。 </li></ol></li></ol> 2.调整纳米棒的长宽比通过改变银离子的浓度<ol><li>制备了4mM的浓度的硝酸银溶液中，溶解3.4毫克的AgNO 3在5毫升水中。 </li><li>在三个不同的小瓶的CTAB溶液和氢醌制备如在1.2.1节中描述的和分别添加100微升，150微升或200微升的硝酸银溶液。 </li><li>根据该氯金酸溶液制备添加步骤1.2.3，并从点1.2.5描述的金纳米棒的准备着手。 </li><li>通过紫外 - 可见光谱和透射电子显微镜表征所获得的纳米棒。与较低的数额的 Ag +小瓶将重新SULT在较短的纳米棒（分别为2和2.2的纵横比）（ 图4）。 </li></ol> 3.通过改变CTAB的浓度调优纳米棒的长宽比<ol><li>在"增长解决方案"准备金纳米棒用不同浓度的CTAB的不同批次。从10mM至100mM使用浓度以产生具有不同大小和宽​​高比金纳米棒。 CTAB在每个实验中所用的浓度列于表1与所用毫克的相应量。在5ml水中22毫克氢醌溶解不同量的CTAB始终。 </li><li>加入200μl的硝酸银溶液（其制备根据步骤1.2.2）和5ml氯金酸4溶液在磁力搅拌下每个小瓶（根据如何在步骤1.2.3中描述的方法制备）。 </li><li>添加12微升种子悬浮液，并观察在最终混合物的颜色变化。 </li><li>停止当该悬浮液的颜色和紫外可见光谱被稳定搅拌;反应时间取决于在生长溶液中的CTAB的浓度。 </li><li>离心在10,000rpm XG的水中10分钟，并重新悬浮。 </li><li>通过紫外 - 可见光谱和透射电子显微镜表征所获得的纳米棒。 CTAB的下部浓度将导致较短的纳米棒而较高浓度将给较长，但较大的纳米棒。上相反的纳米棒的纵横比将在40-50毫米的范围内较高的，并会在较低和较高浓度（ 图5和图6）降低两者。 </li></ol> 4.表征金纳米棒<ol><li> 紫外可见光谱 <ol><li>稀释为100μl用400μl的水纳米棒溶液在塑料微反应杯和获得紫外 - 可见吸收光谱（波长范围400和840纳米之间）根据制造商的协议。 </li><li>收集生长溶液每5分钟的紫外可见光谱（波长范围400和840之间毫微米）为了研究反应的动力学。 </li></ol></li><li> 透射电子显微镜（TEM） <ol><li>收集纳米棒的各样品的TEM图像，对所获得的纳米棒的纵横比的大小的测量。通过将悬浮液（4微升）的下降到一个超薄的Formvar包被的200目铜网上制备样品并保留在4℃下在空气中干燥。根据制造商的协议使用200千伏的加速电压分析在TEM样品。 </li></ol></li></ol>

<ol>
	<li>Zhou, W., Gao, X., Liu, D., Chen, X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gold+Nanoparticles+for+In+Vitro+Diagnostics.">Gold Nanoparticles for In Vitro Diagnostics.</a> Chem Rev. 115 (19), 10575-10636 (2015).</li><li>Bao, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gold+nanoprisms+as+optoacoustic+signal+nanoamplifiers+for+in+vivo+bioimaging+of+gastrointestinal+cancers.">Gold nanoprisms as optoacoustic signal nanoamplifiers for in vivo bioimaging of gastrointestinal cancers.</a> Small. 9 (1), 68-74 (2013).</li><li>Han, G., Ghosh, P., Rotello, V. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Functionalized+gold+nanoparticles+for+drug+delivery.">Functionalized gold nanoparticles for drug delivery.</a> Nanomedicine. 2 (1), 113-123 (2007).</li><li>Choi, W. I., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tumor+regression+in+vivo+by+photothermal+therapy+based+on+gold-nanorod-loaded,+functional+nanocarriers.">Tumor regression in vivo by photothermal therapy based on gold-nanorod-loaded, functional nanocarriers.</a> ACS Nano. 5 (3), 1995-2003 (2011).</li><li>Langille, M. R., Personick, M. L., Zhang, J., Mirkin, C. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Defining+Rules+for+the+Shape+Evolution+of+Gold+Nanoparticles+.">Defining Rules for the Shape Evolution of Gold Nanoparticles .</a> J. Am. Chem. Soc. 134 (35), 14542-14554 (2012).</li><li>Lohse, S. E., Murphy, C. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Quest+for+Shape+Control:+A+History+of+Gold+Nanorod+Synthesis.">The Quest for Shape Control: A History of Gold Nanorod Synthesis.</a> Chem. Mater. 25 (8), 1250-1261 (2013).</li><li>Weissleder, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+clearer+vision+for+in+vivo+imaging.">A clearer vision for in vivo imaging.</a> Nat. Biotech. 19 (4), 316-317 (2001).</li><li>Sau, T. K., Murphy, C. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Seeded+High+Yield+Synthesis+of+Short+Au+Nanorods+in+Aqueous+Solution.">Seeded High Yield Synthesis of Short Au Nanorods in Aqueous Solution.</a> Langmuir. 20 (15), 6414-6420 (2004).</li><li>Ratto, F., Matteini, P., Rossi, F., Pini, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Size+and+shape+control+in+the+overgrowth+of+gold+nanorods.">Size and shape control in the overgrowth of gold nanorods.</a> J. Nanopart. Res. 12, 2029-2036 (2010).</li><li>Morasso, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Control+of+size+and+aspect+ratio+in+hydroquinone-based+synthesis+of+gold+nanorods.">Control of size and aspect ratio in hydroquinone-based synthesis of gold nanorods.</a> J. Nanopart. Res. 17, 330-337 (2015).</li><li>Vigderman, L., Zubarev, E. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High-yield+synthesis+of+gold+nanorods+with+longitudinal+SPR+peak+greater+than+1200+nm+using+hydroquinone+as+a+reducing+agent.">High-yield synthesis of gold nanorods with longitudinal SPR peak greater than 1200 nm using hydroquinone as a reducing agent.</a> Chem. Mater. 25 (8), 1450-1457 (2013).</li><li>Walsh, M. J., Barrow, S. J., Tong, W., Funston, A. M., Etheridge, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Symmetry+breaking+and+silver+in+gold+nanorod+growth.">Symmetry breaking and silver in gold nanorod growth.</a> ACS Nano. 9 (1), 715-724 (2015).</li></ol>

The authors have nothing to disclose.

这里介绍的协议适用于对苯二酚，芳香分子特征是一个弱还原电位，产生金纳米棒。有朝向基础上使用的抗坏血酸的最常用的合成路线本协议的两个主要优点:第一是，对苯二酚能够几乎定量减少金离子允许生产更高量的金纳米棒的11。后者是由它需要的CTAB较低量和成本随后大幅减少的事实给出。本协议是基于一两步方法，与从所述纳米棒的生长的成核步骤的分离涉及。我们注意到由紫外-可见光谱的建议是，所使用的金种子的尺寸被保持约3纳米的非常重要的。8，相反，如果使用具有5nm以上的尺寸较大的种子，我们必然得到球形纳米粒子。 金纳米棒的生长可容易地跟随由紫外 - 可见光谱的装置。杆状颗粒与对应于所述杆的两个不同尺寸的两个明显的峰特征光谱。此外，这种技术可以用于获得根据经验规律所获得的棒的纵横比的第一估计: AR = 0.0078•PP - 3.3 其中Ar是由TEM图像分析确定的经验长宽比和PP是相对于以纳米表示的纵向轴线电浆峰值的位置。第二电浆峰的在光谱的近红外区域的存在是必要的，以确认生产各向异性颗粒。然而，必须注意的是，AR获得由于这个方程是用TEM和U获得的实验结果的只是一个经验相关V型可见光谱和必须确认为产生AuNRs每批。紫外 - 可见光谱证实AuNR的完全形成后，将悬浮液离心以除去过量的CTAB存在于生长溶液，然后将棒悬浮在纯水中，在那里他们似乎是在几个月稳定室内温度。 TEM分析也是必需的AuNR的完整表征，以获取有关的长度和宽度的精确信息。 所得到的纳米粒子的纵横比和尺寸可以以两种方式进行微调。类似的是，在基于抗坏血酸AuNRs的合成常见的做，银离子在生长溶液中的量是能够确定更多或更少的细长形状的形成。银离子诱导形成纳米棒的对称破一次的种子大小达到约5-6纳米。12。因此，较高量的银离子在生长溶液能够诱导更长AuNRs的形成。当具有不同纵横比AuNRs通过这种方法制备，纳米棒的长度可以调谐，但宽度几乎保持恒定并且当最长杆（AR≈3）由只是略有下降。另一个重要参数是CTAB在生长溶液的使用量。 CTAB的浓度已经发现不仅影响长宽比而且纳米棒的大小。有趣的是，所得到的纳米棒的长度线性依赖于CTAB的浓度，纵横比不同的行为，当CTAB是在40和60毫米之间的范围内时，观察到最大。这对应于该棒的宽度在低的CTAB浓度保持恒定的事实，但高于50mM的，杆宽度开始增加引起AR的减少。 总之，我们演示了如何通过应用对苯二酚作还原剂，它是possible。使用大约相比基于由抗坏血酸还原共用通讯协议的CTAB的量的一半，制备纳米棒。尽管这种方法是有限的相对短的金纳米棒具有2和3之间的纵横比的制备，我们期望它可以通过其它基团很容易地通过。这是因为，即使它是基于根据标准抗坏血酸方法的一个小的修改，该方法可以大大提高AuNRs用的成本大幅降低收率。此外，它提供了尺寸和合成的颗粒的纵横比的良好和可靠的控制。因此，所有的这种协议的优点可能是纳米粒子的新的医疗应用更简单，高效的扩散有用，因为这更方便的合成路线将有助于开发生物医学方法，利用纳米棒的临床实践与潜在效益耐心。

金粒子（AuNPs）是在生物医学应用中使用最普遍的和有前途的纳米结构中的一个。其用途是在许多点现场护理体外诊断产品必不可少1他们已经提出作为许多其它不同的应用程序的有效工具:在成像研究的造影剂，2作为药物递送系统3和作为药物的光诱导热疗（或光热疗法）。4金纳米粒子的巨大潜力，带动，在过去的20年里，新合成，能够加大对规模的控制和形状而获得的发展深入研究。5这是因为，不同种类的金纳米粒子的实际上比其他为特定应用更适合。 之间的不同的金的纳米结构，金纳米棒（AuNRs）已成为最有趣的系统之一。 AuNRs的特征在于由两个疟原虫沿着纵向和横向轴线的电子的振荡关联的网卡的峰，分别6是特别重要的是，最激烈的纵向峰值的位置可以被精确调谐620之间以及800纳米，取决于棒的纵横比。这个区域中的生物窗口，7其中人组织几乎不吸收光，允许多项体内涉及金纳米粒子光子应用的发展相匹配。 尽管在这种纳米结构的巨大兴趣，对于AuNRs的制备合成方案从若干限制苦。在大多数的情况下，纳米棒根据由秀和同事开发了两步法来制备。8在它们的协议，纳米棒由减少在预制金种子，银离子和大量的存在下，使用抗坏血酸金离子合成十六烷基三甲基溴化铵（CTAB），交流ationic线性表面活性剂。 这个协议的缺点是，金离子的还原率相对较低（约20％）9和一个高量的CTAB，昂贵的试剂占大于在合成试剂的总成本的一半，是必要的。一个新的，更有效的合成路线的发展是从那里被认为是一个重要的需求，从而允许基于AuNRs生物医学方法的扩展。 在本文件的第一部分中，我们提出对于具有约三长径比制备AuNR的优化协议。的合成是基于使用氢醌作为温和的还原剂，它允许AuNR与一种几乎定量还原金离子的制备中，利用CTAB减少量的10此协议为AuNRs的制备是基于上，其中金种子在"成长溶胶中使用的两​​个步骤的方法ution"。 在第二部分中，我们显示了如何微调得到AuNR的尺寸和纵横比两种方式。第一种方式，类似于基于抗坏血酸的标准协议，是改变存在于"生长溶液"银离子的量。第二种方式是基于可减小到10mM的浓度（接近由供应商报告的临界胶束浓度），以获得良好定义短纳米棒的CTAB的量的变化。

<table border="0" cellpadding="0" cellspacing="0" width="756">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Gold(III) chloride trihydrate</td>
			<td style="width:115px;">Sigma Aldrich</td>
			<td style="width:99px;">520918</td>
			<td style="width:327px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Hydroquinone</td>
			<td>Sigma Aldrich</td>
			<td>H17902</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Silver Nitrate</td>
			<td>Sigma Aldrich</td>
			<td>209139</td>
			<td>toxic</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Sodium Borohydride</td>
			<td>Sigma Aldrich</td>
			<td>480886</td>
			<td></td>
		</tr>
		<tr height="148">
			<td height="148" style="height:148px;width:216px;">Hexadecyltrimethylammonium bromide (CTAB)</td>
			<td>Sigma Aldrich</td>
			<td>H5882</td>
			<td style="width:327px;">Acute Tox. (oral). In this study we tested three different batches of CTAB (H5882) from Sigma Aldrich. Two of them were marked as made in China while one as made in India. In our experience only the batches marked as made in China were effective for the preparation of AuNR</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Spectrophotometer</td>
			<td style="width:115px;">Thermo scientific&#160;</td>
			<td style="width:99px;">Nanodrop 2000C</td>
			<td></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:216px;">TEM</td>
			<td style="width:115px;">JEOL</td>
			<td>2100</td>
			<td></td>
		</tr>
	</tbody>
</table>

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.

金种子紫外可见光谱可以在图1中可以看出。金种子的注射后的不同时间取得的紫外可见光谱示于图呈现2。所得到的金纳米棒的紫外可见光谱和透射电子显微镜（TEM）图像示于图3。金纳米棒与通过改变银离子的量得到的不同的纵横比的紫外可见光谱和透射电子显微镜（TEM）图像证实在图4和CTAB在图5和6的生长溶液。紫外可见光谱是用来观察各向异性金纳米颗粒的形成和得到长宽比的粗略指示。 TEM图像被用于确定纳米结构的形态，以评估AuNRs的精确纵横比和证明的晶体结构黄金。 <img alt="图1" src="/files/ftp_upload/54319/54319fig1.jpg" /> 根据1.1节制备金种子的图1金种子。紫外可见光谱。为了证明种子的尺寸不会太大，必须有没有在505和表征电浆纳米520纳米之间的区域电浆高峰的迹象，所以这个图显示非常小的金种子的存在。 <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/54319/54319fig1large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <img alt="图2" src="/files/ftp_upload/54319/54319fig2.jpg" /> 。由于金种子的喷射在不同的时间获得的金纳米棒的图2.反应动力学紫外可见光谱（CTAB的50mM; 位于 Ag + 200微升）。光谱秀<html>这是最初很红的等离子峰已发生位移，并且逐渐向低波长移动随着时间的推移，直到它变得稳定这表明反应是从种子注入约30分钟后完成。 <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/54319/54319fig2large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <img alt="图3" src="/files/ftp_upload/54319/54319fig3.jpg" /> 根据该协议1.2制备金纳米棒的图3.金纳米棒。TEM图像（左）和UV-可见光光谱（右）。 TEM图像示出了所得到的纳米颗粒的细长形状，通过在紫外可见光谱两者电浆峰的存在证实了，与沿纵向和横向轴线的电子的振荡相关联。透射电镜图像的比例尺为100nm。large.jpg"目标="_空白"&gt;点击此处查看该图的放大版本。 <img alt="图4" src="/files/ftp_upload/54319/54319fig4.jpg" /> 。金纳米棒的图4.金纳米棒的TEM图像（左）和UV-可见光光谱（右）根据使用200微升（A）中的方案2制备150微升（B）和在生长溶液银离子溶液100微升（℃）。作为TEM图像显示，在生长溶液结果在较长的纳米棒中使用较高量的 Ag +的。这也由在保护区的三批最激烈的电浆峰值位置之间的差别证实。透射电镜图像的比例尺为100纳米。 <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/54319/54319fig4large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> 。金纳米棒的图5.金纳米棒的TEM图像（左）和UV-可见光光谱（右）根据使用较低浓度CTAB的部分3制备的:10mM的在生长的CTAB（A）和20毫摩尔（B）的解。在生长溶液中使用的CTAB较低量的结果在较短的纳米棒。比例尺是所有的图片100纳米。 <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/54319/54319fig5large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <img alt="图6" src="/files/ftp_upload/54319/54319fig6.jpg" /> 。金纳米棒的图6.金纳米棒的TEM图像（左）和UV-可见光光谱（右）根据使用较高浓度CTAB的部分3制备的:60毫米（A）; 80mM的（ <strong&gt;的B）和CTAB的100毫米（C）在生长溶液。在纳米棒的使用在生长溶液的结果较高量的CTAB的那些长，但其特征在于由下宽高比。事实上，TEM图像这里报告表明的杆的宽度增加;导致长宽比的减少。比例尺是所有的图片100纳米。 <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/54319/54319fig6large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <img alt="表格1" src="/files/ftp_upload/54319/54319table1.jpg" /> 表1. CTAB的浓度。用于制备金纳米棒的与所获得的不同的纵横比的CTAB的量。

Watch this Scientific Journal Video about Hydroquinone Based Synthesis of Gold Nanorods at JoVE.com

Hydroquinone Based Synthesis of Gold Nanorods

本文描述了金纳米棒的合成一个协议的基础上，使用氢醌作为还原剂，以及用于控制它们的尺寸和纵横比的不同的机制。

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 ...

hydroquinone-based-synthesis-of-gold-nanorods

Nanyang Technological University

Research

JoVE Journal

Chemistry

13.6K 次观看.  Fondazione Don Carlo Gnocchi ONLUS (Don Carlo Gnocchi Foundation). 本文描述了金纳米棒的合成一个协议的基础上，使用氢醌作为还原剂，以及用于控制它们的尺寸和纵横比的不同的机制。 

视频: Hydroquinone Based Synthesis of Gold Nanorods

Template Directed Synthesis of Plasmonic Gold Nanotubes with Tunable IR Absorbance

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

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

的模板导演电浆黄金纳米管的合成与可调谐红外吸收

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

科研

化学

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

As a promising catalytically active nano reactor, gold nanoparticles intercalated in mesoporous silica (GMS) were successfully synthesized and properties of the materials were investigated. We used a one pot sol-gel approach to intercalate gold nano particles in the walls of mesoporous silica. To start with the synthesis, P123 was used as template to form micelles. Then TESPTS was used as a surface modification agent to intercalate gold nano particles. Following this process, TEOS was added in as a silica source which underwent a polymerization process in acid environment. After hydrothermal processing and calcination, the final product was acquired. Several techniques were utilized to characterize the porosity, morphology and structure of the gold intercalated mesoporous silica. The results showed a stable structure of mesoporous silica after gold intercalation. Through the oxidation of benzyl alcohol as a benchmark reaction, the GMS materials showed high selectivity and recyclability.

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 ...

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

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

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

根据环境条件的金纳米粒子的稳定低聚簇的大小控制合成的一种简便方法

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

Photochemical Oxidative Growth of Iridium Oxide Nanoparticles on CdSe@CdS Nanorods

We demonstrate a procedure for the photochemical oxidative growth of iridium oxide catalysts on the surface of seeded cadmium selenide-cadmium sulfide (CdSe@CdS) nanorod photocatalysts. Seeded rods are grown using a colloidal hot-injection method and then moved to an aqueous medium by ligand exchange. CdSe@CdS nanorods, an iridium precursor and other salts are mixed and illuminated. The deposition process is initiated by absorption of photons by the semiconductor particle, which results with formation of charge carriers that are used to promote redox reactions. To insure photochemical oxidative growth we used an electron scavenger. The photogenerated holes oxidize the iridium precursor, apparently in a mediated oxidative pathway. This results in the growth of high quality crystalline iridium oxide particles, ranging from 0.5 nm to about 3 nm, along the surface of the rod. Iridium oxide grown on CdSe@CdS heterostructures was studied by a variety of characterization methods, in order to evaluate its characteristics and quality. We explored means for control over particle size, crystallinity, deposition location on the CdS rod, and composition. Illumination time and excitation wavelength were found to be key parameters for such control. The influence of different growth conditions and the characterization of these heterostructures are described alongside a detailed description of their synthesis. Of significance is the fact that the addition of iridium oxide afforded the rods astounding photochemical stability under prolonged illumination in pure water (alleviating the requirement for hole scavengers).

A protocol for the photochemical oxidative growth of small crystalline iridium oxide nanoparticles on the surface of CdSe@CdS seeded rod nanoparticles is presented.

铱氧化物纳米颗粒对硒化镉硫化镉@纳米棒光化学氧化增长

We demonstrate a procedure for the photochemical oxidative growth of iridium oxide catalysts on the surface of seeded cadmium selenide-cadmium sulfide ...

Synthesis and Evaluation of a Ruthenium-based Mitochondrial Calcium Uptake Inhibitor

We detail the synthesis and purification of a mitochondrial calcium uptake inhibitor, [(OH2)(NH3)4Ru(&#181;-O)Ru(NH3)4(OH2)]5+. The optimized synthesis of this compound commences from [Ru(NH3)5Cl]Cl2 in 1 M NH4OH in a closed container, yielding a green solution. Purification is accomplished with cation-exchange chromatography. This compound is characterized and verified to be pure by UV-vis and IR spectroscopy. The mitochondrial calcium uptake inhibitory properties are assessed in permeabilized HeLa cells by fluorescence spectroscopy.

A protocol for the synthesis, purification, and characterization of a ruthenium-based inhibitor of mitochondrial calcium uptake is presented. A procedure to evaluate its efficacy in permeabilized mammalian cells is demonstrated.

钌线粒体钙吸收抑制剂的合成与评价

We detail the synthesis and purification of a mitochondrial calcium uptake inhibitor, [(OH2)(NH3)4Ru(&#181;-O)Ru(NH3)4(OH2)]5+. The optimized synthesis 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 of Bimetallic Pt/Sn-based Nanoparticles in Ionic Liquids

We demonstrate a method for the synthesis of bimetallic nanoparticles consisting of Pt and Sn. A synthesis strategy is used in which the particular physico-chemical properties of ionic liquids (ILs) are exploited to control both nucleation and growth processes. The nanoparticles form colloidal sols of very high colloidal stability in the IL, which is particularly interesting in view of their use as quasi-homogeneous catalysts. Procedures for both nanoparticle extraction in conventional solvents and for nanoparticle precipitation are presented. The size, structure and composition of the synthesized nanocrystals are confirmed using inductively coupled plasma atomic emission spectroscopy (ICP-AES), X-ray diffraction analysis (XRD) and transmission electron microscopy (TEM) with energy-dispersive X-ray spectroscopy (EDX). By this, we show that the nanocrystals are random-type alloy and of small (2-3 nm) size. The catalytic activity and selectivity in the hydrogenation of &#945;,&#946;-unsaturated aldehydes is tested in a semi-continuous batch-type reactor. In this context, the bimetallic Pt/Sn-based nanoparticles reveal a high selectivity towards the unsaturated alcohol.

A protocol for the synthesis of bimetallic nanoparticles in ionic liquids and the procedure of their catalytic testing in the selective hydrogenation of unsaturated aldehydes are described.

离子液体中双金属 Pt/锡基纳米粒子的合成

We demonstrate a method for the synthesis of bimetallic nanoparticles consisting of Pt and Sn. A synthesis strategy is used in which the particular ...

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 ...

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

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

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

利用 dna 折纸模板将金纳米产物组装成手性质浆细胞分裂体

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

Photodeposition of Pd onto Colloidal Au Nanorods by Surface Plasmon Excitation

A protocol is described to photocatalytically guide Pd deposition onto Au nanorods (AuNR) using surface plasmon resonance (SPR). Excited plasmonic hot electrons upon SPR irradiation drive reductive deposition of Pd on colloidal AuNR in the presence of [PdCl4]2-. Plasmon-driven reduction of secondary metals potentiates covalent, sub-wavelength deposition at targeted locations coinciding with electric field &#8220;hot-spots&#8221; of the plasmonic substrate using an external field (e.g., laser). The process described herein details a solution-phase deposition of a catalytically-active noble metal (Pd) from a transition metal halide salt (H2PdCl4) onto aqueously-suspended, anisotropic plasmonic structures (AuNR). The solution-phase process is amenable to making other bimetallic architectures. Transmission UV-vis monitoring of the photochemical reaction, coupled with ex situ XPS and statistical TEM analysis, provide immediate experimental feedback to evaluate properties of the bimetallic structures as they evolve during the photocatalytic reaction. Resonant plasmon irradiation of AuNR in the presence of [PdCl4]2- creates a thin, covalently-bound Pd0 shell without any significant dampening effect on its plasmonic behavior in this representative experiment/batch. Overall, plasmonic photodeposition offers an alternative route for high-volume, economical synthesis of optoelectronic materials with sub-5 nm features (e.g., heterometallic photocatalysts or optoelectronic interconnects).

A protocol for anisotropic photodeposition of Pd onto aqueously-suspended Au nanorods via localized surface plasmon excitation is presented.

通过表面等离子体激发将 Pd 光沉积到胶体 Au 纳米棒上

A protocol is described to photocatalytically guide Pd deposition onto Au nanorods (AuNR) using surface plasmon resonance (SPR). Excited plasmonic hot ...