我们要感谢马修·贝克J.博士，现在斯特拉斯克莱德大学，格拉斯哥与拉曼实验和尼克·冈特先生的支持，他之前这个项目的工作。

注意:在此工作中使用的CNT是在相比其散装同行可具有额外的危害纳米颗粒形式。石墨吸入，天然和合成，可引起尘肺62相似，煤工尘肺。此外，已经有关于碳纳米结构的毒性和一些以前的研究的关注建议与碳纳米管63-68的吸入有关的急性和慢性毒性。因此，避免了细CNT粉吸入，并且十分小心处理。如吸入，移至空气新鲜处。如呼吸困难，用纯氧代替，并就医。碳纳米管的溶液/分散液的配方是相当安全的。 注意:脂质和本研究中使用的表面活性剂是食品级材料和一般因而无危险，但是它们刺激眼睛和皮肤，并且也高度易燃。因此，请使用所有适当的安全实践，例如使用的ENgineering控制（通风橱）和个人防护装备（护目镜，手套，实验室外套，全长裤，封闭趾鞋）办理或准备时，纳米粒子样本。在与皮肤或眼睛，应立即冲洗眼睛或皮肤用大量的水至少15分钟的接触情况。如果需要就医。 1.脂质/散装水相的制备注意:在4℃存放在冰箱中的脂质。纯级脂质应贮存在冰箱中（-20℃）。它们分装成小玻璃瓶中，以避免整个股市和处理方便的污染。其他化学物质，包括碳纳米管和表面活性剂可以储存在室温下，但让他们远离阳光直射。 <ol><li>保持脂质， 即的Dimodan U（DU）和植烷三醇（PT）在RT之前，以避免湿气凝结开瓶/小瓶的盖子15-20分钟。 （注:杜是一个蒸馏甘油酯含有96％的单酸甘油酯和其余的二甘油酯和游离脂肪酸。在杜两个主要单甘油酯组分是亚油酸（62％）和油酸（25％）。因此，DU的疏水部分主要含有C18链（91％），其确切的组合物的是如下; C18:2（61.9％），C 18:1（24.9％），和C18:0（4.2％），其中C 18表示18C-链和冒号后的数字表示的C = C键数目。 PT是3,7,11,15-四甲基-1,2,3- hexadecanetriol光学异构体的混合物。它不含有酯官能团，而是由高度支化的phytanyl尾巴与三羟基首基的。既杜和PT的形成的过量的水存在下这也是稳定的脂质颗粒13，45）的芯的情况下立方相。 </li><li>通过将小瓶在热水浴中或60℃以上保持一含有烧杯水融化脂质（加热磁力搅拌器:230伏，50赫兹，630 W或类似被用于加热水在烧杯中）。 </li><li>使用块加热器或者热小瓶。不加热直接包含在热板上小瓶脂质，以避免温度梯度和随后的脂质分解。 </li><li>称量500毫克的熔化的脂类的，在预先称重的离心管（带锥形卡扣帽，1.5毫升），用巴斯德玻璃吸管用胶乳灯泡。 </li><li> 500毫升超纯水（水电阻率= 18.2MΩ·厘米）添加到上述离心管中。 </li><li>手动混合组分使用微小（定制）锅铲15分钟。通过平坦化用钳子注射器针头（0.9毫米×40毫米套管长度）的尖端做出这样的刮刀。 </li><li>离心机以2,000×g的速度的脂质/水混合物10分钟。再次手动搅拌该混合物10分钟，然后平衡它24小时。表征样品之前，鼓动他们为5分钟，然后让它们在室温。 </li><li>以确保在整个管的平衡脂质相的形成，进行大约10次冻融循环和INTE<html> rmittently进行离心步骤定义如上。两者的杜和PT形式高度粘稠散装脂质相使得难以手动处理它们（图1）。 注:上述协议（第1部分），仅需要，如果一个人想比较纳米结构的行为（晶格型和自组装的尺寸）分散颗粒与散装脂质相和/或使用它作为一个控制确认原来的纳米结构的保留。 </li></ol><img alt="图1" src="/files/ftp_upload/53489/53489fig1.jpg" /> 图1.使用高能量输入（超声波），并使用不同的CNT-稳定剂，即SWCNT，与从高粘度脂类相流体一致性O / W颗粒乳液的制备碳纳米管-OH，MWCNT-COOH（图来自参考转载[50]从化学的英国皇家学会的许可）。_upload / 53489 / 53489fig1large.jpg"目标="_空白"&gt;点击此处查看该图的放大版本。 2.表面活性剂的制备稳定的脂质颗粒<ol><li>制备出0.2％（W ​​/ W）表面活性剂（普朗尼克F127）的水溶液中。 <ol><li>通过搅拌，约20-30分钟（使用磁力搅拌棒的磁性板）溶解200毫克在100毫升的超纯水的表面活性剂（白色蓬松粉末）。普朗尼克F127是一种非离子表面活性剂和通常用作乳化稳定剂。它是PEO 99 -PPO 67 -PEO 99的三嵌段共聚物，因此需要很长的时间在水中溶解。 </li></ol></li><li> 500毫克熔融杜或PT（使用巴斯德玻璃吸管）添加到玻璃小瓶（闪烁钠钙装有箔衬里尿素帽，20ml）中。 </li><li>加上9.5克0.2％F127的解决方案。 </li><li>探头超声机，紧紧夹住瓶的铁架台颚（铁架台与设置站，钳，碱，棒，橡胶3颚和bosshead），使得它能够承受通过超声处理产生的振动。 </li><li>插入连接于细胞超声仪的实心钛合金探针英寸（13毫米直径×139毫米长度）。调整小瓶的高度和位置，以确保它的侧面和底部没有接触到探针。的探针和玻璃小瓶的底部在0.5厘米的距离给出了良好的结果。 </li><li>超声处理在1秒脉冲的脉冲模式，在35％的功率（最大的）1秒的延迟时间调节为10分钟该混合物。小瓶会变得非常热，由于超声处理过程中产生的热量。因此，允许它取下来钳前冷却至室温。 </li><li>存储在RT乳白色形成的分散至少24小时之前，进一步使用。这是为了确保其对相分离的稳定性。 注意:在与使用探头后，用纸巾用丙酮清洗，干燥，然后用超纯水的冲洗ð再一次擦干。 </li></ol> 3.水纯碳纳米管的分散体的制备<ol><li>在两个独立的烧杯，权衡4毫克粉末状的MWCNT-OH和MWCNT-COOH，这两者都是黑色的。 </li><li> 500毫升超纯水添加到每个烧杯中。使用探针超声波发生器在40％超声处理2分钟的混合物以连续脉冲模式功率（最大的）。所得的碳纳米管分散液的浓度为8微克/毫升（原液）。 </li><li>稀释碳纳米管原液用超纯水的适当量达到6.25，5,4，2微克/毫升MWCNT分散体。 </li><li>超声振荡如前所述，这些分散体（见3.2）。 </li><li>同样地，在500毫升的超纯水分散3毫克粉末状的单壁碳纳米管的（也黑色的），以使一个6微克/毫升SWCNT分散液（原液）。 </li><li>稀释SWCNT原液和超声处理他们以上（见图3.2）所描述获得0.5，0.4，0.3125，0.2微克/毫升SWCNT dispersions。 注意:所有的分散体都清楚约30分钟，在此之后，碳纳米管在底部开始沉降。 </li></ol> 4.制备CNT-中稳定的纳米脂质颗粒的（图1） <ol><li>称重在500毫克熔融杜到玻璃小瓶中。 </li><li>添加9.5的6微克/毫升的单壁碳纳米管分散液的小瓶中的溶液。 </li><li>使用相同的参数超声处理在CNT-DU混合物作为用于制备纯的CNT分散体（见3.2）。在冷却至RT，用保守内部自组装纳米结构的碳纳米管稳定脂质颗粒将准备。 </li><li>以类似的方式，使用0.4微克/毫升和0.2微克/毫升的单壁碳纳米管分散液制备所述脂质颗粒。 </li><li>按照协议4.1到4.4，以使使用MWCNT-OH和MWCNT-COOH，但使用不同浓度的，即8,4和2微克/毫升的CNT的脂质颗粒。 </li><li>同样，使用准备4微克/毫升MWCNT-OH和多壁碳纳米管三种不同的CNT-PT分散-COOH以及0.4微克/毫升的单壁碳纳米管。注意，CNT-PT分散体需要较少功率（最大的35％），但在连续脉冲模式较长的时间（15分钟）。冷却分散体RT和表征之前离开他们24小时。 注意:超声参数可能对于不同的脂类不同（如在DU和PT这里）和不同的组合物;它们需要被优化，以实现良好的稳定化的分散体。 </li></ol> 5.监控CNT稳定脂质分散体的稳定性<ol><li>监控分散体通过视觉观察稳定性:检查分散体不稳定或肿块于分散体已经形成。 </li><li>定期取（用数码相机）的照片。例如，采取分散的照片每天都在第一个星期，然后每隔一天一个星期后每周一次，接下来的两个星期，最后每月一次按要求。 </li></ol>

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脂质颗粒的稳定 三种不同的碳纳米管用于稳定脂质分散体;其中两个是多壁和用-OH和-COOH基团官能化的，一种是单壁和非官能（原始）。碳纳米管的尺寸变化如下（直径×长度）:MWCNT-COOH:9.5纳米×1.5微米;碳纳米管-OH:8-15纳米×50微米; SWCNT:1-2纳米点¯x1-3微米。粉状碳纳米管通过探针的超声波处理分散在水中。碳纳米管的上述大小可能进一步下降，由于超超声，尽管并不均衡。在纯净水的CNT分散体开始约20分钟，因此，进一步的工作是这个时间 ，即内执行，此外血脂和第二超声处理后分离。后者（在脂质-CNT的混合物进行超声处理）有助于熔融和分解的水化进入亚微米的部分中形成大的和不一致的脂质域。分散大量脂类我n这方式有助于平衡形成自组装纳米结构，其中另有要求严格冻融循环和/或长的时间（几天至几周）的。散装脂相闯入纳米粒子，而脂类包裹碳纳米管理应形成他们周围的炮弹。超声处理提高了碳纳米管和脂质分子，从而装饰脂质烷基链CNT的烷基链之间的疏水相互作用。由此涂覆的碳纳米管稳定分散的脂质相导致的颗粒乳液。这种相互稳定避免碳纳米管的聚集，以及分散的脂质颗粒。这种分散体也被称为皮克林（由于使用固体颗粒）型油包水（O / W）乳液，其中该脂质形成"油相"，而"过量的水"构成连续乳液介质（图1 ）。超声参数（脉冲长度，延迟时间和功率），稳定剂的理化参数（例如，尺寸，功能化），分散体的分散相和组合物的浓度（例如，CNT与脂质比）是保证分散体的最终稳定性至关重要，因此，需要为不同的（脂）系统进行优化。 CNT的优化脂质比率稳定的乳状液 广泛范围的浓度为每CNT型（图2）的混合物来稳定从两个不同的脂质获得的自组装纳米结构。然而，仅形成在碳纳米管脂质比率的特定范围均匀且稳定的乳状液;过高比率导致碳纳米管的聚集，而太低的比率导致不稳定的乳液，因为没有足够的碳纳米管以完成足够的颗粒表面覆盖。最佳稳定状态被发现用3-5微克/毫升之间浓度MWCNT-COOH和MWCNT-OH，而对于SWCNT在0.3-0.45的范围内微克/毫升。 脂质颗粒的形态学特征 在SAXS测量验证PT的该脂质颗粒保留原始立方相纳米结构体（由本体相示出）（图3A）。我们推定该立方相也保留在杜颗粒情况下，然而，这需要进一步的确认，因为它是不是在当前工作中研究。对于PT散装Pn3m阶段观察到的晶格常数为6.84纳米，分散时增加至7.1纳米。散相的下晶格参数是由于缺少过量的水，其可以通过Ia3d相（ 在图3A中标记以*的峰）的共存来也证实。该Ia3d阶段通常是有限的水资源条件下找到。为所有分散脂质颗粒观察Pn3m相的晶格参数 （即，通过表面活性剂以及由所有的CNT类型稳定的）是practicallŸ同样表明多余的水分条件。这也排除了在哪些，否则，可能引发的脂质相的变化相关的分子水平的CNT驱动扰动的可能性。 该cubosomes的粒径分布由体积加权分布给出如图 3B所示。虽然CNT稳定颗粒表现有较大的粒度分布，多数颗粒显示尺寸532-760纳米的表面活性剂稳定的脂质颗粒（674纳米），这是媲美的大小之间。 碳纳米管涂脂 对于纯碳纳米管，典型的拉曼石墨条带出现在拉曼光谱。其对应于&#39;CC键&#39;，D带（未示出）的面内振动这是由于在碳系统病症和G&#39;带的存在这归因于D带的泛音G带70清楚地观察到。当interacti对CNT的脂质和CNT形成稳定的脂质颗粒（比较图 4中的绿色和蓝色曲线），一转移到较高的波数（蓝移）是观察。所观察到的蓝移，可能是由于:ⅰ）高压力超声波期间的CNT导致其分散施加相对于成束状态时纯70,71，和/或经由CNT的涂层ⅱ）碳纳米管和脂质分子间的相互作用由脂质（如蓝移以前已由Douroumis 等 72脂类包裹的单壁碳纳米管报道）。 在碳纳米管的峰和脂质信号的外观（从纯脂质（图4）的红色曲线相对强度的降低进一步证实了脂质分子CNT的涂层。这表明脂质分子碳纳米管和烷基链之间的疏水相互作用装饰在亲水头基面临水的地区从而stabili这样CNT表面诚O / W乳液，如由在图4D的示意图。 我们已经证明了的动力学稳定使用不同的碳纳米管纳米脂质颗粒的O / W型乳液智能，简便的方法。非常低浓度的碳纳米管（&lt;10微克/毫升）是足够的，以稳定的脂质纳米颗粒分散体，其用于体内应用特别有前途。脂质分子碳纳米管的装饰预期，同时提高其生物相容性，以尽量减少其毒性。脂质自组装内以及在CNT表面上装载功能分子的前景提供对抗主要疾病73无限潜力在生物医学科学尤其是用在联合疗法的上下文中的区域的碳纳米管稳定脂质颗粒。

在过去的几十年中，纳米技术已成为一个强大的工具，特别是在医学打击臭名昭著疾病如癌症1的临床前开发的领域。在这种情况下，用尺寸&lt;1000nm的广泛探索作为各种活性生物分子如药物，蛋白质，核酸，基因和诊断显像剂1-4的递送载体的纳米级结构。这些生物分子的纳米颗粒内的任一胶囊或缀合到纳米粒子的表面和由触发器如pH或温度5,6-在作用部位被释放。尽管在尺寸非常小，这些纳米颗粒的表面积大证明是活性生物分子的靶向递送大大有利的。在粒度和生物相容性的控制是最重要的，以优化治疗效果，因此纳米颗粒7,8的适用性。9-13脂质，聚合物14,15，16,17的金属和碳纳米管18,19已被广泛用作纳米载体各种生物医学和制药应用。 此外，基于脂质的自组装纳米结构纳米载体的应用在许多其它领域，包括食品和化妆品行业20,21宽的意义。例如，它们在蛋白质结晶22，生物分子23的分离的使用，如食品稳定剂例如在甜点24，和在活性分子如营养物质，风味剂和香料25-31的交付。自组装的脂质纳米结构不仅必须释放生物活性分子在受控和靶向方式32-38的能力，但他们也能保护功能分子从化学和酶降解39,40。虽然平面流体双层是最通讯由两亲脂质分子在水存在下形成的纳米结构，其他的结构，例如六方和立方通常也观察到20,41,42。纳米结构体的类型取决于脂质"分子形状的结构，在水中的脂质组合物，以及对温度和压力43采用这样的物理化学条件。非平面脂质纳米结构的适用性特别是立方相的，是因为它们的高粘度和非均相域一致性的限制。这些问题是由分散在大量的水中的脂质纳米结构，以形成油包水（O / W）含有微米或亚微米大小的脂质颗粒乳剂克服。在这种方式下，低粘度的合适的产品能够在保持分散颗粒内的原始脂质自组装结构来制备。这些内部自组装的颗粒的形成（简称为ISAsomes 44 </sup&gt; 例如，从立方相和六角相hexosomes）cubosomes通常需要高能量输入步骤以及加入稳定剂，例如表面活性剂或聚合物的组合。在这个方向最近的研究表明，包括二氧化硅纳米颗粒46，粘土47-49和碳纳米管50前述乳液，适当称为皮克林51或拉姆斯登-Pickering乳液52的稳定各种固体颗粒45的应用程序。 近年来，碳基纳米结构如单壁碳纳米管（单壁碳纳米管），多壁碳纳米管（多壁碳纳米管）和富勒烯已收到的极大关注作为新型生物材料53,54。主要关注的是其毒性55-58，不溶于水，59和因此他们的生物相容性56。解决这些问题的有效方法是在表面功能alization采用无毒和生物相容分子如脂类。在水存在，脂类的方式与碳纳米管相互作用，碳纳米管的疏水表面由极性水性介质屏蔽而脂质的亲水性头部基团有助于在水中60,61它们的溶解度或分散体。脂质是细胞器以及一些食品材料的组成成分，因此其装饰应理想降低CNT的体内毒性 。在碳纳米管18,19和脂质纳米结构9-13基于独立医学领域的应用正在广泛开展，但是，结合两者的性能应用尚未充分探讨。 在这项工作中，我们使用两种不同类型的脂质和三种类型的碳纳米管，其中单壁碳纳米管是在纯净的形式，而多壁碳纳米管与羟基和羧酸基团官能化。我们已经使用非常低浓度的碳纳米管制备的分散体稳定性取决于几个因素如脂质的类型，碳纳米管的种类，脂质至CNT使用的，以及对电力和持续时间采用这种超声处理参数比。此视频协议提供的动力学稳定使用各种CNT-稳定脂质纳米粒的方法的技术细节。

<table border="0" cellpadding="0" cellspacing="0" width="1468">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:281px;">Dimodan U</td>
			<td style="width:312px;">Danisco</td>
			<td style="width:119px;">15312</td>
			<td style="width:756px;">Store at 4&#176;C, Non-hazardous. Irritant to eyes and skin</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:281px;">Phytantriol (&#62; 95%, GC)</td>
			<td style="width:312px;">TCI Europe N.V.</td>
			<td style="width:119px;">P1674</td>
			<td>Store at 4&#176;C, Non-hazardous. Irritant to eyes and skin</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Single walled Carbon Nanotubes (90%)</td>
			<td>Nanostructured &#38; Amorphous Materials, Inc.&#160;</td>
			<td>1246YJS</td>
			<td>Store at room temperature. Away from direct light. Irritating to eyes, skin and respiratory system</td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;width:281px;">Multi-walled carboxylic acid functionalised Carbon Nanotubes (&#62; 80% Caron basis, &#62; 8% carboxylic acid functionalized)</td>
			<td style="width:312px;">Sigma-Aldrich Co. LLC&#160;</td>
			<td style="width:119px;">755125</td>
			<td>Store at room temperature. Away from direct light. Causes serious eye irritation. May cause respiratory irritation</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:281px;">Graphitized Multi-walled hydroxy functionalised Carbon Nanotubes (99.9%)</td>
			<td style="width:312px;">Nanostructured &#38; Amorphous Materials, Inc. (NanoAmor)&#160;</td>
			<td style="width:119px;">1224YJF</td>
			<td>Store at room temperature. Away from direct light. Irritating to eyes, skin and respiratory system</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:281px;">Pluronic F127</td>
			<td style="width:312px;">Sigma-Aldrich Co. LLC&#160;</td>
			<td style="width:119px;">P2443</td>
			<td>BioReagent, suitable for cell culture. Not a hazardous substance or mixture. Store at room temperature.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:281px;">Acetone (99.5%)</td>
			<td style="width:312px;">Fisher Scientific&#160;</td>
			<td>10134100</td>
			<td>Highly flammable liquid. Causes serious eye irritation. May cause drowsiness or dizziness</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:281px;">Scintillation Vial</td>
			<td style="width:312px;">VWR International Ltd</td>
			<td style="width:119px;">548&#8208;0704</td>
			<td>Soda&#8208;lime glass vial with low background count Fitted with foil lined urea cap, 20 ml</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Jars with loose, enfolding lids (375ml)</td>
			<td style="width:312px;">VWR International Ltd</td>
			<td>216-3308</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:281px;">Beaker , 1000mL</td>
			<td style="width:312px;">Fisher Scientific&#160;</td>
			<td style="width:119px;">12942161</td>
			<td>heavy duty, low form, with spout and graduations</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:281px;">Pasteur glass pipette (150 mm length) with latex bulb</td>
			<td style="width:312px;">Fisher Scientific&#160;</td>
			<td style="width:119px;">10006021</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:281px;">Microcentrifuge tube conical snap cap 1.5mL</td>
			<td style="width:312px;">Fisher Scientific&#160;</td>
			<td style="width:119px;">11558232</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:281px;">Spatula</td>
			<td style="width:312px;">Fisher Scientific&#160;</td>
			<td style="width:119px;">11352204</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:281px;">Heating magnetic stirrer</td>
			<td style="width:312px;">Fisher Scientific&#160;</td>
			<td style="width:119px;">11715704</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:281px;">Magnetic stirrer bars (cylindrical, opaque PTFE, 30mm x 7mm (l x diameter))</td>
			<td style="width:312px;">Fisher Scientific&#160;</td>
			<td style="width:119px;">10011792</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:281px;">Needle (0.9 mm x 40 mm cannula length)</td>
			<td>Terumo UK Ltd</td>
			<td>MN-2038MQ</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:281px;">Retort Stand Set - With stand, clamp, base, rod, rubber 3 jaw and bosshead</td>
			<td style="width:312px;">Camlab Ltd, UK</td>
			<td>1177157</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:281px;">Millipore water equipment</td>
			<td style="width:312px;">Barnstead Nanopure, Thermoscientific, USA</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="43">
			<td height="43" style="height:43px;width:281px;">Progen Genfuge 24D Digital Microcentrifuge</td>
			<td style="width:312px;">Progen Scientific</td>
			<td>C-2400</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Probe ultra-sonicator, with 13 mm&#160;</td>
			<td>SONICS, Vibracell,&#160; USA</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">5MP camera with auto-focus and LED flash</td>
			<td>Samsung Galaxy Fame Mobile camera</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:281px;">Raman Spectrometer</td>
			<td style="width:312px;">Horiba Jobin-Yvon LabRAM HR800 spectrometer</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:281px;">Mastersizer 3000</td>
			<td colspan="2">&#160;Malvern Instruments Ltd, Malvern, United Kingdom</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Small angle X-ray scattering (SAXS)</td>
			<td colspan="3">SAXSpace camera (Anton Paar, Graz, Austria), X-ray generating equipment (ISO-DEBYEFLEX3003, GE Inspection Technologies GmbH), closed water circuit (Chilly 35, HYFRA, Germany).&#160;</td>
		</tr>
	</tbody>
</table>

facile preparation of internally self-assembled lipid particles stabilized by carbon nanotubes

我们提出了一种简便的方法，制备由碳纳米管（CNT）稳定的纳米结构的脂质颗粒。单壁（原始）和多壁（官能化）碳纳米管被用作稳定剂，以产生皮克林类型油包水（O / W）乳剂。脂质即的Dimodan U和植烷三醇用作乳化剂，其在过量的水自组装成的双连续立方Pn3m相。高粘度的阶段被分成使用传统的表面活性剂稳定剂或为这里所做的碳纳米管的存在探头超声波发生器更小的粒子。最初，碳纳米管（粉末形式）分散在水中，然后进一步超声与熔化的脂类以形成最终乳液。在此过程中的CNT得到涂覆有脂质分子，这反过来又被假定为包围脂滴，以形成微粒乳状液是稳定数月。 CNT-中稳定的纳米结构的脂质颗粒的平均尺寸是在亚微米ř法兰，这与颗粒比较好使用常规的表面活性剂稳定化。相比于纯脂质相（散装状态）小角X射线散射数据证实原始Pn3m立方相在CNT-中稳定的脂质分散液的滞留。蓝移和在特性G和拉曼光谱观察到碳纳米管的G&#39;带的强度的降低表征碳纳米管表面和脂质分子之间的相互作用。这些结果表明，在碳纳米管和脂质之间的相互作用是负责在水溶液中相互稳定。作为稳定化所用的碳纳米管的浓度是非常低的和脂质分子能够官能化碳纳米管，碳纳米管的毒性预计是微不足道，而他们的生物相容性大大提高。因此，本方法发现在各种生物医学应用的巨大潜力，例如用于开发混合纳米载体系统m的输送ultiple功能分子如在联合治疗中或polytherapy。

下面的结果表示）的分散体的稳定性，二）脂质颗粒的尺寸分布，三）自组装以及d的类型）对于CNT的脂质包衣的证据。分散体的稳定性（ 图2）用一个500万像素的摄像头，支持自动对焦和LED闪光灯监控。 <img alt="图2" src="/files/ftp_upload/53489/53489fig2.jpg" /> 图2.得到仅在一定区域内的稳定乳液的CNT类型（A）的MWCNT-OH，（B）的MWCNT -COOH，和（C）的单壁碳纳米管和相应的乳液的图片。的示意图 （阴影），其中所述CNT脂比例为最佳;低于和高于稳定的乳液没有形成，因为CNT的一个过少或过多大量的，分别为。箭头指示处于不稳定的乳液典型的CNT肿块。这些测量是对一个范围，DU-CNT分散体进行; representative的人都在这里显示（数字从参考文献[50]从皇家化学学会许可转载）。 <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/53489/53489fig2large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> 小角度X射线散射（SAXS）模式被记录，以确定稳定isasomes（图3A）的内纳米结构的晶格类型。该SAXSpace相机连接到一个分析X射线生成设备（ISO-DEBYEFLEX3003）具有密封管铜阳极，在40千伏和50毫安工作。在X射线管被冷却与封闭水回路。所述SAXSpace准直块单位转换发散的多色X射线束到铜的Kαα辐射的具有波长λ，0.154纳米垂直聚焦线形光束。用于SAXS实验被选为该高分辨率模式中，其中，permits检测0.04毫微米-1（Q =（4π/λ）SINθ，其中2θ为散射角）的最小散射矢量，Q 分钟，。半透明波束停止使记录衰减初级束轮廓零散射向量和发送校正的精确测定。所研究的样品中的每一个封闭在同一真空密封，可重复使用的1毫米石英毛细管，以保证完全一样的散射体积。毛细管置于装有珀尔帖元件，其被连接到水冷却调温摆脱多余的热量的温度控样品阶段。所有实验均在25℃为0.1℃的温度下的稳定性进行。真空泵用于抽空所述样本室达到〜1毫巴的最小压力。一维散射图案进行记录的微带X射线检测器。这个探测器是单光子计数并具有SENSIT64×8 平方毫米面积IVE包括用0.05×8毫米（V×高）的通道大小每1,280通道。样品 - 检测器距离为317.09毫米。每个样品暴露三次300秒，和它们的集成散射轮廓进行平均。 该SAXStreat软件采用相对于该主光束的位置以校正散射图案。在SAXS数据是通过在q = 0的统一设定减毒散射强度进一步传输校正和背景用的是SAXSQuant软件减去。散射矢量 q与银山萮酸，其具有5.84纳米69已知的晶格间距校准。所有记录，衍射图案可以与空间群Pn3m（金刚石双连续立方相），其中，110，111，200，211，220和221的反射进行鉴定（图3A）进行索引。洛杉矶ttice参数， 一 ，为Pn3m相通过施加下面的晶格方程的线性回归来确定 一个 = 2π/ Q HKL×√（H 2 + K 2 + 1 2）（1） 其中 ，h，k和l是米勒指数。 使用激光粒径analyer测定分散的脂质颗粒的尺寸和尺寸分布（图3B）。 <img alt="图3" src="/files/ftp_upload/53489/53489fig3.jpg" /> 图3。 </strong&gt;（A）的SAXS散装植烷三醇（PT）和相应的使用F127和不同的CNT的稳定剂中过量的水，5％（重量）的PT制备的分散体中观察到的Pn3m相位的模式。上Pn3m相，这是一种双连续立方相，其结构是基于双金刚石（D）型最小表面的单元电池的右侧显示部分中所示的三维示意图。蓝箭头表示以四面体角度水渠道会议，而疏水性和水性区域的颜色编码分别为黄色和蓝色。为Pn3m相位特征峰被索引为√2，√3，√4，√6，√8，√9和相应米勒指数中的括号中。上述所有峰都在散装PT可见，而前四个反射是对分散可见;不过这足以识别Pn3m纳米结构，并评估其晶格参数。高峰强调bý星号表示Ia3d型立方相，它通常具有较低的水含量形成，并因此未分散的共存。与&#39;立方纳米结构"在其内部脂质颗粒通常称为"cubosomes&#39;。 （B）cubosomes的粒度分布由静态光散射测量使用各种稳定剂制备的。 <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/53489/53489fig3large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> 使用拉曼光谱（图4）进行了研究的碳纳米管和脂质颗粒之间的相互作用。样品:碳纳米管，脂质和CNT稳定脂质颗粒进行脱水，首先使用氮气，然后通过使它们保持在真空干燥器中约20分钟。使用Horiba乔宾-Yvon公司的LabRam HR800分光计配备有安道尔的光谱记录<html>电磁铁电荷耦合器件（CCD），用于光探测和视频摄像机以指导光谱集合。钕的532 nm激发线:YAG激光来收集光谱范围100-4,000厘米- 1采用600克光栅毫米- 1闪耀在750纳米。用0.50数值孔径50X长工作距离物镜被用于获取光谱和共焦孔设定在100微米。在测量之前，仪器被校准到520.8厘米-硅的1谱线。所有光谱上放置氟化钙载玻片将样品在RT（25℃）搜集。谱用的532纳米激光获取并积累5次，用1％曝光10秒。用于加工预原始数据和即时数据询问LabSpec 6光谱软件套件。 ftp_upload / 53489 / 53489fig4.jpg"/&gt; 图4.拉曼光谱为脱水（A）的纯脂质，MWCNT-COOH和CNT-稳定的含5.0微克/毫升MWCNT-COOH，（B）的纯脂质，MWCNT-OH含脂质纳米颗粒和脂质纳米粒5.0微克/毫升MWCNT- OH，含有0.3125微克/毫升SWCNT和（C）的纯脂质，单壁碳纳米管和脂质纳米颗粒。所有曲线代表10谱，其中强度，以任意单位绘制与波长的平均值。垂直线用于指导的眼睛，以缓解在G和G&#39;带的蓝移的检测。这些实验是在DU进行。在碳纳米管表面（图来自文献[50]从皇家化学学会许可转载）（D）可能脂质装饰（自组装）的示意图。 <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/53489/53489fig4large.jpg" target="_blank">请点击此处为vi</a>EW这个数字的放大版本。

Watch this Scientific Journal Video about Facile Preparation of Internally Self-assembled Lipid Particles Stabilized by Carbon Nanotubes at JoVE.com

Facile Preparation of Internally Self-assembled Lipid Particles Stabilized by Carbon Nanotubes

We report on a smart application of carbon nanotubes for kinetic stabilization of lipid particles that contain self-assembled nanostructures in their cores. The preparation of lipid particles requires rather low concentrations of carbon nanotubes permitting their use in biomedical applications such as drug delivery.

内部自组装脂质颗粒的简易制备碳纳米管稳定

We present a facile method to prepare nanostructured lipid particles stabilized by carbon nanotubes (CNTs). Single-walled (pristine) and multi-walled ...

facile-preparation-internally-self-assembled-lipid-particles

Nanyang Technological University

Research

JoVE Journal

Chemistry

9.5K 次观看.  University of Central Lancashire. We report on a smart application of carbon nanotubes for kinetic stabilization of lipid particles that contain self-assembled nanostructures in their cores. The preparation of lipid particles requires rather low concentrations of carbon nanotubes permitting their use in biomedical applications such as drug delivery.

视频: Facile Preparation of Internally Self-assembled Lipid Particles Stabilized by Carbon Nanotubes

Production of Disulfide-stabilized Transmembrane Peptide Complexes for Structural Studies

Physical interactions among the lipid-embedded alpha-helical domains of membrane proteins play a crucial role in folding and assembly of membrane protein complexes and in dynamic processes such as transmembrane (TM) signaling and regulation of cell-surface protein levels. Understanding the structural features driving the association of particular sequences requires sophisticated biophysical and biochemical analyses of TM peptide complexes. However, the extreme hydrophobicity of TM domains makes them very difficult to manipulate using standard peptide chemistry techniques, and production of suitable study material often proves prohibitively challenging. Identifying conditions under which peptides can adopt stable helical conformations and form complexes spontaneously adds a further level of difficulty. Here we present a procedure for the production of homo- or hetero-dimeric TM peptide complexes from materials that are expressed in E. coli, thus allowing incorporation of stable isotope labels for nuclear magnetic resonance (NMR) or non-natural amino acids for other applications relatively inexpensively. The key innovation in this method is that TM complexes are produced and purified as covalently associated (disulfide-crosslinked) assemblies that can form stable, stoichiometric and homogeneous structures when reconstituted into detergent, lipid or other membrane-mimetic materials. We also present carefully optimized procedures for expression and purification that are equally applicable whether producing single TM domains or crosslinked complexes and provide advice for adapting these methods to new TM sequences.

Biophysical and biochemical studies of interactions among membrane-embedded protein domains face many technical challenges, the first of which is obtaining appropriate study material. This article describes a protocol for producing and purifying disulfide-stabilized transmembrane peptide complexes that are suitable for structural analysis by solution nuclear magnetic resonance (NMR) and other analytical applications.

生产二硫键稳定的跨膜肽复合物的结构研究

Physical  interactions among the lipid-embedded alpha-helical domains of membrane  proteins play a crucial role in folding and assembly of membrane ...

科研

化学

Covalent Binding of BMP-2 on Surfaces Using a Self-assembled Monolayer Approach

Bone morphogenetic protein 2 (BMP-2) is a growth factor embedded in the extracellular matrix of bone tissue. BMP-2 acts as trigger of mesenchymal cell differentiation into osteoblasts, thus stimulating healing and de novo bone formation. The clinical use of recombinant human BMP-2 (rhBMP-2) in conjunction with scaffolds has raised recent controversies, based on the mode of presentation and the amount to be delivered. The protocol presented here provides a simple and efficient way to deliver BMP-2 for in vitro studies on cells. We describe how to form a self-assembled monolayer consisting of a heterobifunctional linker, and show the subsequent binding step to obtain covalent immobilization of rhBMP-2. With this approach it is possible to achieve a sustained presentation of BMP-2 while maintaining the biological activity of the protein. In fact, the surface immobilization of BMP-2 allows targeted investigations by preventing unspecific adsorption, while reducing the amount of growth factor and, most notably, hindering uncontrolled release from the surface. Both short- and long-term signaling events triggered by BMP-2 are taking place when cells are exposed to surfaces presenting covalently immobilized rhBMP-2, making this approach suitable for in vitro studies on cell responses to BMP-2 stimulation.

We describe a method for accomplishing efficient immobilization of BMP-2 on surfaces. Our approach is based on the formation of a self-assembled monolayer to achieve the covalent binding of BMP-2 via its free amine residues. This method is a useful tool to study signaling at the cell membrane.

BMP-2的共价结合利用表面上的自组装单层膜法

Bone morphogenetic protein 2 (BMP-2) is a growth factor embedded in the extracellular matrix of bone tissue. BMP-2 acts as trigger of mesenchymal cell ...

Transport of Surface-modified Carbon Nanotubes through a Soil Column

Carbon nanotubes (CNTs) are widely manufactured nanoparticles, which are being utilized in a number of consumer products, such as sporting goods, electronics and biomedical applications. Due to their accelerating production and use, CNTs constitute a potential environmental risk if they are released to soil and groundwater systems. It is therefore essential to improve the current understanding of environmental fate and transport of CNTs. The transport and retention of CNTs in both natural and artificial media have been reported in literature, but the findings widely vary and are thus not conclusive. There are a number of physical and chemical parameters responsible for variation in retention and transport. In this study, a complete procedure of selected multiwalled carbon nanotubes (MWCNTs) is presented starting from their surface modification to a complete set of laboratory column experiments at critical physical and chemical scenarios. Results indicate that the stability of the commercially available MWCNTs are critical with their attached surface functional group which can also influence the transport and retention of MWCNT through the surrounding medium.

Surface properties of a nanoparticle are important for their interaction with the surrounding medium. Therefore the surface modification of carbon nanotubes can be critical for their transport and retention through porous media. Here, lab scale column experiments are used to understand the possible transport and retention of these nanoparticles.

表面修饰碳纳米管通过土柱运输

Carbon nanotubes (CNTs) are widely manufactured nanoparticles, which are being utilized in a number of consumer products, such as sporting goods, ...

Facile and Efficient Preparation of Tri-component Fluorescent Glycopolymers via RAFT-controlled Polymerization

Synthetic glycopolymers are instrumental and versatile tools used in various biochemical and biomedical research fields. An example of a facile and efficient synthesis of well-controlled fluorescent statistical glycopolymers using reversible addition-fragmentation chain-transfer (RAFT)-based polymerization is demonstrated. The synthesis starts with the preparation of &#946;-galactose-containing glycomonomer 2-lactobionamidoethyl methacrylamide obtained by reaction of lactobionolactone and N-(2-aminoethyl) methacrylamide (AEMA). 2-Gluconamidoethyl methacrylamide (GAEMA) is used as a structural analog lacking a terminal &#946;-galactoside. The following RAFT-mediated copolymerization reaction involves three different monomers: N-(2-hydroxyethyl) acrylamide as spacer, AEMA as target for further fluorescence labeling, and the glycomonomers. Tolerant of aqueous systems, the RAFT agent used in the reaction is (4-cyanopentanoic acid)-4-dithiobenzoate. Low dispersities (&#8804;1.32), predictable copolymer compositions, and high reproducibility of the polymerizations were observed among the products. Fluorescent polymers are obtained by modifying the glycopolymers with carboxyfluorescein succinimidyl ester targeting the primary amine functional groups on AEMA. Lectin-binding specificities of the resulting glycopolymers are verified by testing with corresponding agarose beads coated with specific glycoepitope recognizing lectins. Because of the ease of the synthesis, the tight control of the product compositions and the good reproducibility of the reaction, this protocol can be translated towards preparation of other RAFT-based glycopolymers with specific structures and compositions, as desired.

An efficient, three-step synthesis of RAFT-based fluorescent glycopolymers, consisting of glycomonomer preparation, copolymerization, and post-modification, is demonstrated. This protocol can be used to prepare RAFT-based statistical glycopolymers with desired structures.

通过RAFT控制聚合轻便和高效制备三组分荧光Glycopolymers

Synthetic glycopolymers are instrumental and versatile tools used in various biochemical and biomedical research fields. An example of a facile and ...

Preparation of Carbon Nanosheets at Room Temperature

Amphiphilic molecules equipped with a reactive, carbon-rich "oligoyne" segment consisting of conjugated carbon-carbon triple bonds self-assemble into defined aggregates in aqueous media and at the air-water interface. In the aggregated state, the oligoynes can then be carbonized under mild conditions while preserving the morphology and the embedded chemical functionalization. This novel approach provides direct access to functionalized carbon nanomaterials. In this article, we present a synthetic approach that allows us to prepare hexayne carboxylate amphiphiles as carbon-rich siblings of typical fatty acid esters through a series of repeated bromination and Negishi-type cross-coupling reactions. The obtained compounds are designed to self-assemble into monolayers at the air-water interface, and we show how this can be achieved in a Langmuir trough. Thus, compression of the molecules at the air-water interface triggers the film formation and leads to a densely packed layer of the molecules. The complete carbonization of the films at the air-water interface is then accomplished by cross-linking of the hexayne layer at room temperature, using UV irradiation as a mild external stimulus. The changes in the layer during this process can be monitored with the help of infrared reflection-absorption spectroscopy and Brewster angle microscopy. Moreover, a transfer of the carbonized films onto solid substrates by the Langmuir-Blodgett technique has enabled us to prove that they were carbon nanosheets with lateral dimensions on the order of centimeters.

We present the synthesis of an amphiphilic hexayne and its use in the preparation of carbon nanosheets at the air-water interface from a self-assembled monolayer of these reactive, carbon-rich molecular precursors.

碳纳米片在室温下准备

Amphiphilic molecules equipped with a reactive, carbon-rich "oligoyne" segment consisting of conjugated carbon-carbon triple bonds self-assemble into ...

Facile Preparation of 4-Substituted Quinazoline Derivatives

Reported in this paper is a very simple method for direct preparation of 4-substituted quinazoline derivatives from a reaction between substituted 2-aminobenzophenones and thiourea in the presence of dimethyl sulfoxide (DMSO). This is a unique complementary reaction system in which thiourea undergoes thermal decomposition to form carbodiimide and hydrogen sulfide, where the former reacts with 2-aminobenzophenone to form 4-phenylquinazolin-2(1H)-imine intermediate, whilst hydrogen sulfide reacts with DMSO to give methanethiol or other sulfur-containing molecule which then functions as a complementary reducing agent to reduce 4-phenylquinazolin-2(1H)-imine intermediate into 4-phenyl-1,2-dihydroquinazolin-2-amine. Subsequently, the elimination of ammonia from 4-phenyl-1,2-dihydroquinazolin-2-amine affords substituted quinazoline derivative. This reaction usually gives quinazoline derivative as a single product arising from 2-aminobenzophenone as monitored by GC/MS analysis, along with small amount of sulfur-containing molecules such as dimethyl disulfide, dimethyl trisulfide, etc. The reaction usually completes in 4-6 hr at 160 &#186;C in small scale but may last over 24 hr when carried out in large scale. The reaction product can be easily purified by means of washing off DMSO with water followed by column chromatography or thin layer chromatography.

A protocol for facile preparation of 4-substituted quinazoline derivatives from 2-aminobenzophenones, thiourea and dimethyl sulfoxide is presented.

的4-取代喹唑啉衍生物简便制备

Reported in this paper is a very simple method for direct preparation of 4-substituted quinazoline derivatives from a reaction between substituted ...

Functionalization of Single-walled Carbon Nanotubes with Thermo-reversible Block Copolymers and Characterization by Small-angle Neutron Scattering

We demonstrate a protocol for single-walled carbon nanotube functionalization using thermo-sensitive PEO-PPO-PEO triblock copolymers in an aqueous solution. In a carbon nanotube/PEO105-PPO70-PEO105 (poloxamer 407) aqueous solution, the amphiphilic poloxamer 407 adsorbs onto the carbon nanotube surfaces and self-assembles into continuous layers, driven by intermolecular interactions between constituent molecules. The addition of 5-methylsalicylic acid changes the self-assembled structure from spherical-micellar to a cylindrical morphology. The fabricated poloxamer 407/carbon nanotube hybrid particles exhibit thermo-responsive structural features so that the density and thickness of poloxamer 407 layers are also reversibly controllable by varying temperature. The detailed structural properties of the poloxamer 407/carbon nanotube particles in suspension can be characterized by small-angle neutron scattering experiments and model fit analyses. The distinct curve shapes of the scattering intensities depending on temperature control or addition of aromatic additives are well described by a modified core-shell cylinder model consisting of a carbon nanotube core cylinder, a hydrophobic shell, and a hydrated polymer layer. This method can provide a simple but efficient way for the fabrication and in-situ characterization of carbon nanotube-based nano particles with a structure-tunable encapsulation.

A method for the functionalization of carbon nanotubes with structure-tunable polymeric encapsulation layers and structural characterization using small-angle neutron scattering is presented.

单壁碳纳米管与热可逆嵌段共聚物及表征功能化小角度中子散射

We demonstrate a protocol for single-walled carbon nanotube functionalization using thermo-sensitive PEO-PPO-PEO triblock copolymers in an aqueous ...

Highly Stable, Functional Hairy Nanoparticles and Biopolymers from Wood Fibers: Towards Sustainable Nanotechnology

Nanoparticles, as one of the key materials in nanotechnology and nanomedicine, have gained significant importance during the past decade. While metal-based nanoparticles are associated with synthetic and environmental hassles, cellulose introduces a green, sustainable alternative for nanoparticle synthesis. Here, we present the chemical synthesis and separation procedures to produce new classes of hairy nanoparticles (bearing both amorphous and crystalline regions) and biopolymers based on wood fibers. Through periodate oxidation of soft wood pulp, the glucose ring of cellulose is opened at the C2-C3 bond to form 2,3-dialdehyde groups. Further heating of the partially oxidized fibers (e.g., T = 80 &#176;C) results in three products, namely fibrous oxidized cellulose, sterically stabilized nanocrystalline cellulose (SNCC), and dissolved dialdehyde modified cellulose (DAMC), which are well separated by intermittent centrifugation and co-solvent addition. The partially oxidized fibers (without heating) were used as a highly reactive intermediate to react with chlorite for converting almost all aldehyde to carboxyl groups. Co-solvent precipitation and centrifugation resulted in electrosterically stabilized nanocrystalline cellulose (ENCC) and dicarboxylated cellulose (DCC). The aldehyde content of SNCC and consequently surface charge of ENCC (carboxyl content) were precisely controlled by controlling the periodate oxidation reaction time, resulting in highly stable nanoparticles bearing more than 7 mmol functional groups per gram of nanoparticles (e.g., as compared to conventional NCC bearing &#60;&#60; 1 mmol functional group/g). Atomic force microscopy (AFM), transmission electron microscopy (TEM), and scanning electron microscopy (SEM) attested to the rod-like morphology. Conductometric titration, Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), dynamic light scattering (DLS), electrokinetic-sonic-amplitude (ESA) and acoustic attenuation spectroscopy shed light on the superior properties of these nanomaterials.

Synthesis schemes to prepare highly stable wood fiber-based hairy nanoparticles and functional cellulose-based biopolymers have been detailed.

高稳定性，功能性毛纳米粒子和木纤维生物聚合物:迈向可持续纳米技术

Nanoparticles, as one of the key materials in nanotechnology and nanomedicine, have gained significant importance during the past decade. While ...

Facile Synthesis of Worm-like Micelles by Visible Light Mediated Dispersion Polymerization Using Photoredox Catalyst

Presented herein is a protocol for the facile synthesis of worm-like micelles by visible light mediated dispersion polymerization. This approach begins with the synthesis of a hydrophilic poly(oligo(ethylene glycol) methyl ether methacrylate) (POEGMA) homopolymer using reversible addition-fragmentation chain-transfer (RAFT) polymerization. Under mild visible light irradiation (&#955; = 460 nm, 0.7 mW/cm2), this macro-chain transfer agent (macro-CTA) in the presence of a ruthenium based photoredox catalyst, Ru(bpy)3Cl2 can be chain extended with a second monomer to form a well-defined block copolymer in a process known as Photoinduced Electron Transfer RAFT (PET-RAFT). When PET-RAFT is used to chain extend POEGMA with benzyl methacrylate (BzMA) in ethanol (EtOH), polymeric nanoparticles with different morphologies are formed in situ according to a polymerization-induced self-assembly (PISA) mechanism. Self-assembly into nanoparticles presenting POEGMA chains at the corona and poly(benzyl methacrylate) (PBzMA) chains in the core occurs in situ due to the growing insolubility of the PBzMA block in ethanol. Interestingly, the formation of highly pure worm-like micelles can be readily monitored by observing the onset of a highly viscous gel in situ due to nanoparticle entanglements occurring during the polymerization. This process thereby allows for a more reproducible synthesis of worm-like micelles simply by monitoring the solution viscosity during the course of the polymerization. In addition, the light stimulus can be intermittently applied in an ON/OFF manner demonstrating temporal control over the nanoparticle morphology.

This article describes a process for producing polymeric self-assembled nanoparticles using visible light mediated dispersion polymerization. Using low energy visible light to control the polymerization allows for the reproducible formation of self-assembled worm-like micelles at high solids content.

使用Photoredox催化剂蠕虫状胶束的简便合成可见光介导的分散聚合

Presented herein is a protocol for the facile synthesis of worm-like micelles by visible light mediated dispersion polymerization. This approach begins ...

Anionic Polymerization of an Amphiphilic Copolymer for Preparation of Block Copolymer Micelles Stabilized by &#960;-&#960; Stacking Interactions

In this study, an amphiphilic copolymer that includes a core-forming block with phenyl groups was synthesized by living anionic polymerization of phenyl glycidyl ether (PheGE) on methoxy-polyethylene glycol (mPEG-b-PPheGE). Characterization of the copolymer revealed a narrow molecular distribution (PDI &#60; 1.03) and confirmed the degree of polymerization of mPEG122-b-(PheGE)15. The critical micelle concentration of the copolymer was evaluated using an established fluorescence method with the aggregation behavior evaluated by dynamic light scattering and transmission electronic microscopy. The potential of the copolymer for use in drug delivery applications was evaluated in a preliminary manner including in vitro biocompatibility, loading and release of the hydrophobic anti-cancer drug doxorubicin (DOX). A stable micelle formulation of DOX was prepared with drug loading levels up to 14% (wt%), drug loading efficiencies &#62; 60% (w/w) and sustained release of drug over 4 days under physiologically relevant conditions (acidic and neutral pH, presence of albumin). The high drug loading level and sustained release is attributed to stabilizing &#960;-&#960; interactions between DOX and the core-forming block of the micelles.

The key steps of living anionic polymerization of phenyl glycidyl ether (PheGE) on methoxy-polyethylene glycol (mPEG-b-PPheGE) are described. The resulting block copolymer micelles (BCMs) were loaded with doxorubicin 14% (wt%) and sustained release of drug over 4 days under physiologically relevant conditions was obtained.

一个两亲性共聚物的阴离子聚合通过π-π堆积作用稳定嵌段共聚物胶束的制备

In this study, an amphiphilic copolymer that includes a core-forming block with phenyl groups was synthesized by living anionic polymerization of phenyl ...