批种子佛罗里达大学 - 医学院表示感谢。研究生研究（曼努埃尔·萨利纳斯）支持在生物医学研究计划 - 研究计划，科学强化（MBRS RISE）奖学金:NIH / NIGMS R25的GM061347通过少数机会。从华莱士的H. Coulter基金会通过佛罗里达国际大学的财政支持，也感谢生物医学工程系。最后，感谢他们协助学生在实验过程中不同阶段的:玛拉基书萨特尔卡马乌码头，肯德尔·阿姆斯特朗和亚伯拉罕·阿方索。

1。准备<ol><li>设计并制作一个组件，以适应一个三单张阀的几何。这将包括在最小的阀保持器缝合的瓣叶的管，以容纳阀保持架及周边配件将组件固定到脉冲复制器系统。在我们的例子中，我们使用的市售的脉冲复印机系统可从ViVitro实验室公司（维多利亚，不列颠哥伦比亚省）。阀保持架的设计，以及前处理和后处理的组件的配置如图1中所示。 </li><li>需要在使用前将底漆整个循环。这包括两个步骤:ⅰ）清洗整个环路系统使用肥皂溶液和水洗涤，包括在使用前更换任何退化管，和ii）连接到环路的工具的校准，即所使用的泵，流量探针，压力传感器（通常是心房，主动脉和心室的位置测量）。校准可以初始化ially进行，用1％食盐水之前，应重复使用模拟血液甘油溶液。 </li></ol> 2。主动脉瓣切除术<ol><li>获得4个新鲜的猪心，从美国农业部批准的屠宰场（机构动物护理和使用委员会（IACUC）批准可能需要）的主动脉完好无损。在我们的例子中，我们解剖协议IACUC佛罗里达国际大学（议定书"批准文号:11-020）批准。心，用去离子水冲洗，并将其放置在一个盛器，填充有1％抗生素和抗真菌剂/无菌磷酸盐缓冲盐水（PBS）溶液和运输冰流体动力测试实验室。 </li><li>心中解剖盘，小心地取出心包。定位腹侧正面临着你的心。目视检查，并确定心脏的四个腔室，并找到完整的主动脉主动脉弓。 </li><li>分离心脏重量ö半部横跨约0.75水平下方的环形带， 即主动脉和左心室之间的交界处。小心地分离出完整的主动脉仍连接到左心室组织分部。 </li><li>检查位于主动脉瓣在主动脉根部，升主动脉和下侧的环形带之间的区域，确保没有任何损坏或钙化的任何迹象。 </li><li>分裂主动脉〜1在该环形带的上方和下方的环形带的左心室组织分部分离，以分离主动脉瓣（ 图2a）。 </li></ol> 3。聚合物和Native阀缝合过程<ol><li>将每个阀的基础上，与后支架的基础上的阀保持架内的心脏瓣膜。在每个阀门在固定的地方后，暂时用一个回形针，但要小心，不要损坏或牙尖commissures。 </li><li>插入缝合于针。开始缝合在阀保持架的底部，通过将注射针刺入第一孔，从外侧到内侧，使得针可能会很容易地从底部拉出。以循环的方式，开始垂直缝合阀的阀门支架的职位。 </li><li>沿圆周的保持器和安全的持有人的职位的前端周围的附加 ​​的缝合的缝合（ 图2b）中的进展情况。可以去除回形针（ 图2c），当阀门完全使用缝线固定的3个职位，并在阀支架（ 图2d和2e）的圆周。 </li></ol> 4。液力评价注意:实际协议将取决于所使用的特定的脉冲复制系统。所有的信息caontained所用的，ViVitro脉冲，速印机SYSYTEM（ViVitro实验室，温哥华，BC）。 <ol><li>双向单张VA绿萼<ol><li>设置脉冲复印机系统70次/分钟的心脏速率。 </li><li>选择的流波形驱动泵（的ViVitro系统的情况下，S35的波形被选定为所有流体动力学测试）。在我们的实验中使用的特定的波形示出由Lim 等 （2001）17。 </li><li>开启对放大器和活塞泵。热身15分钟。 </li><li>将双向单张阀（ 图2f）在主动脉的位置。 </li><li>涂抹真空油脂的所有路口的设备可能发生泄漏的地方。 </li><li>倒入心房室甘油/盐水液体。需要注意的是的搏动复印机系统运行在2 L的液体:35％/ 0.7升甘油和65％/ 1.3 L的盐溶液。盐溶液的制备使用常见的盐溶解在去离子水中的浓度为9毫克/毫升（重量/体积）。 </li><li>打开，已经被放置在主动脉的位置上的流量传感器。 </li><li>校准日ê泵。 </li><li>继续其次由压力传感器流量传感器校准。同样的泵，只需按照指示由ViVitest软件（ViVitro Labs公司）为每个校准标签下的流量和压力。 </li><li>一旦校准完成后，启动泵在低转速，直到流体填充主动脉舱。检查是否有泄漏。使用真空油脂如有必要。 </li><li>关闭两个停止公鸡（主动脉和心室传感器的）到打开位置。 </li><li>提高泵的转速，直到每搏输出量达到80毫升/节拍。 </li><li>允许系统运行10分钟，直到流稳定。流量稳定，可以验证通过观察波形显示在屏幕中的流量和压力。低到没有周期之间的变化是系统稳定的一个很好的指标。 </li><li>在ViVitest软件，选择采集模式。 </li><li>点击收集10个周期。 </li><li>从分析模式，C舔桌子上，并保存该文件。还可以用照片捕捉选项ViVitest保存图像的波形。 </li></ol></li><li>母语和聚合物阀门<ol><li>对于聚合物和动物阀，按照同样的步骤3.1.1 - 3.1.3双向单张阀指令。 </li><li>阀支架放置与缝合阀玻璃管内的定制组件。夹在中间管件的顶部和底部，并就地与横向的螺钉和螺母固定。 </li><li>将组件之间的的主动脉腔室和原来的主动脉瓣支架。 </li><li>继续步骤3.1.5 - 3.1.16双向单张阀指令。 </li></ol></li></ol> 5。后处理<ol><li>流量和压力波形<ol><li>平均的波形采集的， 即主动脉压（AP），左心室压力（VP），流量（Q）对每个收集到的数据。 </li><li>对于每个组的阀（聚合物，猪Ñ积极行动的主动脉瓣和双向单张），绘制相应的AP，VP和Q随时间变化的关系，在同一小区。 </li><li>对于AP，叠加正常，主动脉阀18，和双向单张瓣膜19地块从文献为验证目的。 </li></ol></li><li>水动力指标<ol><li>对于测试的每个阀，下面的流体动力度量计算:a）前流动压力降和最大跨瓣压差（TVP），二）主动脉根均方（RMS）的前向气流率，三）主动脉前向气流，关闭，泄漏总返流量，D）底阀口面积（EOA），电子）远期transaortic，流动，收盘时，泄漏和总能量损失。 <ol><li>正向流压降计算从TVP的读数，并可以分为3个时间段，P:TVP，F:正向流量和H间隔:间隔0 TVP开始和结束0流量开始和结束的时间间隔。最大TVP是马ximum记录的压力梯度跨瓣的主动脉和心室压力读数。 </li><li> RMS正向流速（Q 有效值 ）提供了一个有用的指标为量化前向流速的大小，如下所示: <img alt="公式1" fo:src="/files/ftp_upload/50335/50335eq1highres.jpg" src="/files/ftp_upload/50335/50335eq1.jpg" /> 其中"n"是时间点的总数收集，"Q 我 "是收集，以&#39;我&#39;的瞬时流量测量。 </li><li>前进，主动脉关闭和泄漏量的计算基于以下的时间间隔，远期:开始向前流经阀（T O），年底前向流量（T 1）;结算:从T 1至实例（T 2）阀门关闭;泄漏:从T 2至年底的心脏周期（T 3）。总返流量是简单相加的CLOSING和泄漏量。 </li><li>为20，P，F和H的3个时间间隔期间的平均TVP上述各期间的EOA血液属性的基础上，可以计算: <img alt="公式1" fo:src="/files/ftp_upload/50335/50335eq2highres.jpg" src="/files/ftp_upload/50335/50335eq2.jpg" /></li><li>能源损耗被定义如下:21日 : <img alt="公式1" fo:src="/files/ftp_upload/50335/50335eq3highres.jpg" src="/files/ftp_upload/50335/50335eq3.jpg" /></li></ol></li></ol></li></ol>

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什么都没有透露。

在本研究中，我们已经展示了实用程序的修改市售搏动复印机单元，容纳三单张阀的几何形状，使流体动力学的聚合物和天然猪阀的测试可以执行。特别是在我们的案例中，系统改良是一个的左ViVitro心脏和全身模拟器通过ViViTest的数据采集系统（ViVitro系统公司，维多利亚，不列颠哥伦比亚省，加拿大）控制系统（ 图1a）。然而，该系统是没有不同，不同的试管中 ，都利用一种双组分的Windkessel模型模仿的流量和压力相关的波形人体循环22-25的脉动流的循环。在这些双组分弹性朦系统通常由搏动泵，合规室，模仿的动脉的扩张性，和一个外周阻力的控制器，可用于调节血管阻力。的方程，它描述了两个组件管理NT Windkessel模型是: <img alt="式（4）" fo:src="/files/ftp_upload/50335/50335Seq4highres.jpg" src="/files/ftp_upload/50335/50335Seq4.jpg" /> 其中C是遵守，R代表电阻，Q（t）是作为时间的函数的体积流速和P是动脉压（ 即无论是在肺动脉或主动脉）。在此背景下，我们相信，类似的修改，可容纳三单张，以及在其他搏动模拟器的阀门。特别是在我们的例子中，容纳三单张阀结构于主动脉瓣位置，组装主要的丙烯酸塑料外壳（有机玻璃）包含一个快速原型的阀门支架和缝合三单张阀（ 图1B和1C）很容易地集成和除去从主ViVitro系统。流体动力学测试，随后进行了类似的鲍德温等人进行的其他研究。26Wang 等人 25瞬时流率的测定是使用的电磁流量计系统（ 图3）。实时测量的压力的时间的记录，可在心室和导管的位置，上面一组心率为70次/分钟（ 图4和5）使用微尖的换能器。测试流体是模拟血液的液体，其特征在于，包括去离子水，甘油在65％至35％的比例和9克/升的NaCl，模仿血液黏稠度（约3.3厘泊）。 我们初步测试了双向单张机械阀和所获得的平均压力波的形式进行了比较，文献值19。有些心室压力变化观察，可能是由于不同的泵机制，来推动流体流动，以及几何形状和具体设置不同的脉冲复制系统，如心室腔的大小，具体阀模仿二尖瓣位置，心脏速率选择，生理流动波形选择等 。主动脉波形另一方面，被认为是非常相似，并且独立于系统的。重复这个练习为本地猪阀和再次心室压力变化较大时，观察我们的研究结果进行比较的文献18篇。然而，重要的是要注意，在我们的系统中，瞬时流量以及心室和主动脉的压力相似无论阀进行了测试， 即聚合物和原生的未经组装的组装或双向单张。本练习是重要的执行，因为需要确保复印机系统的修改与程序集的本地流量和/或压力的条件下没有显着改变。其次，这些结果表明，作为一种手段的系统验证，在最小，比较主动脉压力需要导出跨脉冲复制系统平台或测试阀。的解释流体力学变量本身是一件个别聚合物阀门的设计细节。 ISO（国际标准化组织）5840中使用的心脏瓣膜假体的评价标准，例如可以作为指导，以评估与聚合物阀的几何形状，制造和材料特性相关的各种参数。这些参数可以进一步优化和流体力学随后重新测试，以确保符合FDA提交所需的标准。 例如，在我们的聚合物阀门，可比能耗损失和降低返流卷与本地和双向单张阀的建议可接受的工作量左心室21和高效的阀门关闭（ 表1）。但是，收盘导致较高的聚合物阀最大TVP梯度（与双向单张阀），在我们的例子中，认股权证进一步的机械评估有机硅材料是我们的动力制造阀，以确保较高的应力不会导致单张破裂，可放在适当的位置，有足够的安全系数。总之，我们已经证明，包括一壳体单元，玻璃管和阀保持架的组件容纳三单张如聚合物可以缝合在位置的阀的结构，可以制造。比较的流量和压力波形跨越本地的，假肢和正在开发的聚合物阀需要以以下方式获得。二，压力波形与文献值需要进行验证。我们的做法是一个局限心室波形脉冲复印机系统特定的，有可能以示区别;然而主动脉压力波形应与被测试，如果存在足够的阀功能，跨平台或阀门。这项工作的未来方向是进一步优化聚合物阀门材料，制造工艺和几何。流体力学测试WIL升随后重复相同的条件下，以便确定如果功能上的改进通过比较当前和以前的计算流体动力学度量定量观察。

心脏瓣膜病往往导致退行性瓣膜钙化1，风湿热，心内膜炎3,4或先天性出生缺陷。当阀门出现损坏，引起管腔狭窄和/或关闭不全瓣脱垂并不能进行手术修复，本土阀门通常是人工瓣膜替换。当前可用的选项包括机械阀（笼式球阀，倾斜盘阀等 ），同种移植，和生物瓣膜（猪和牛的阀门）。机械阀通常建议年轻的患者，根据其耐用性，但患者须继续抗凝治疗，以防止血栓并发症5。同种生物的人工心脏瓣膜一直有效的选择，以避免血液稀释剂治疗，然而，这些阀门有纤维化的风险升高，钙化，变性，导致阀故障6和免疫原性并发症。组织工程阀门被调查作为一项新兴的技术7-9，但仍然有许多有待发现。替代耐用，生物相容性，人工心脏瓣膜，心脏瓣膜疾病患者的生活质量需要改善。同样，这种阀门设计可以取代使用生物瓣经导管瓣膜技术，导管方法的潜力转化患者选择的治疗心脏瓣膜病10。 诚如，一个成功的心脏瓣膜替代现行标准应具有以下性能特点:1）允许正向流动与可接受的小型平均压差下降; 2）防止逆行流可接受小返流; 3）抗栓塞; 4）抵抗溶血; 5）抗血栓形成; 6）具有生物相容性; 7）是在体内诊断技术兼容; 8）交付和植入目标人口9）保持固定一次放置10）有一个可以接受的噪音水平; 11）具有重复性的功能; 12），维持其功能为合理的寿命，符合其泛型类; 13）一个合理的架子，维护其功能和不育生活在植入前。"11。一些现有的瓣膜的缺点可能被克服的聚合物阀被认为是生物相容的聚合物的生物稳定性，抗水解，抗氧化，和有利的机械性能，如基于顶端候选人特别是高强度和粘弹性，弹性聚合物可提供材料的变形，类似本土阀的动态。弹性体可以定制，以模仿软组织属性，它们可能是唯一的人造材料，生物性，并能承受耦合， 在体内 ，流体引起的，弯曲和拉伸应力，但移动的方式类似健康本地阀动作。此外，弹性体可以是大规模生产的各种各样的大小的信息，存储轻松，预期是符合成本效益的设备，并可以在结构上与纤维增强材料增强。 采用高分子材料组装一个三单张阀的概念并不新鲜，在过去的50年12月放弃了，这是主要是由于阀经久耐用有限，一直受到一些研究调查。然而，随着新型制造方法的出现，13,14，加固高分子材料15,16和潜在的无缝集成聚合物阀经导管瓣膜技术的替代品，有最近被重新开发聚合物阀门作为一个潜在的兴趣和活动当前可用的商业阀的可行的替代方案。在这个光中，一个协议，用于使这些阀的测试，以评估水动力的功能是第一步在评估过程中，但一般市售脉冲模拟器系统不配备，容纳三单张阀设计，并包含一个环形间距插入市售心脏瓣膜（ 如倾盘，双向单张机械心脏瓣膜）。其次，聚合物阀门是一项新​​兴技术，其流体力学只能在一个相对范围内评估。即使本机的心脏瓣膜的压力和流量的数据是可用的，所以重要的是，进行测试猪主动脉阀，这是人类阀生物相似，使用相同的搏动模拟器，用于评估的聚合物阀以便解释测量的差异，可能取决于系统。因此，这项研究的目标是演示如何市售脉冲模拟器可以配备容纳三单张阀的结构组件和系统评估聚合物阀门流体动力指标在相对续转比较机械和天然猪心脏瓣膜同行的。在我们的例子中，小说三单张有机硅聚合物阀以前开发的大学的佛罗里达州13包括聚合物阀门组。

<table border="1">
	<tbody>
		<tr>
			<td>Name of Reagent/Material</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
		</tr>
		<tr>
			<td>Pump</td>
			<td>ViVitro Labs</td>
			<td></td>
			<td><a href="http://vivitrolabs.com/products/superpump/" target="_blank">http://vivitrolabs.com/products/superpump/</a></td>
		</tr>
		<tr>
			<td>Flow Meter and Probe</td>
			<td>Carolina Medical</td>
			<td>Model 501D</td>
			<td><a href="http://www.carolinamedicalelectronics.com/documents/FM501.pdf" target="_blank">http://www.carolinamedicalelectronics.com/documents/FM501.pdf</a></td>
		</tr>
		<tr>
			<td>Pressure Transducer</td>
			<td>ViVitro Labs</td>
			<td>HCM018</td>
			<td></td>
		</tr>
		<tr>
			<td>ViVitro Pressure Measuring Assembly</td>
			<td>ViVitro Labs</td>
			<td>6186</td>
			<td></td>
		</tr>
		<tr>
			<td>Valve holder</td>
			<td>WB Engineering</td>
			<td></td>
			<td>Designed by Florida International University. Manufactured by WB Engineering</td>
		</tr>
		<tr>
			<td>Pulse Duplicator</td>
			<td>ViVitro Labs</td>
			<td>PD2010</td>
			<td><a href="http://vivitrolabs.com/wp-content/uploads/Pulse-Duplicator-Accessories1.pdf" target="_blank">http://vivitrolabs.com/wp-content/uploads/Pulse-Duplicator-Accessories1.pdf</a></td>
		</tr>
		<tr>
			<td>Pulse Duplicator Data Acquisition and Control System, including ViViTest Software</td>
			<td>ViVitro Labs</td>
			<td>PDA2010</td>
			<td><a href="http://vivitrolabs.com/products/software-daq" target="_blank">http://vivitrolabs.com/products/software-daq</a></td>
		</tr>
		<tr>
			<td>Porcine Hearts and Native Aortic Valves</td>
			<td>Mary&#39;s Ranch Inc</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Bi-leaflet Mechanical Valves</td>
			<td>Saint Jude Medical</td>
			<td></td>
			<td><a href="http://www.sjm.com/" target="_blank">http://www.sjm.com/</a></td>
		</tr>
		<tr>
			<td>High Vacuum Grease</td>
			<td>Dow Corning Corporation</td>
			<td></td>
			<td><a href="http://www1.dowcorning.com/DataFiles/090007b281afed0e.pdf" target="_blank">http://www1.dowcorning.com/DataFiles/090007b281afed0e.pdf</a></td>
		</tr>
		<tr>
			<td>Glycerin</td>
			<td>McMaster-Carr</td>
			<td>3190K293</td>
			<td>99% Natural 5 gal</td>
		</tr>
		<tr>
			<td>Phosphate Buffered Saline (PBS)</td>
			<td>Fisher Scientific</td>
			<td>MT21031CV</td>
			<td>100 ml/heart</td>
		</tr>
		<tr>
			<td>Antimycotic/Antibiotic Solution</td>
			<td>Fisher Scientific</td>
			<td>SV3007901</td>
			<td>1 ml in 100 ml of PBS/heart; 20 ml for ViVitro System</td>
		</tr>
		<tr>
			<td>NaCl</td>
			<td>Sigma-Aldrich</td>
			<td>S3014-500G</td>
			<td>9 g/L of deionized water</td>
		</tr>
		<tr>
			<td>Deionized Water</td>
			<td>EMD Millipore Chemicals</td>
			<td></td>
			<td>Millipore Deionized Purification System. 1.3 L for ViVitro System, 200 ml for heart valve dissection process</td>
		</tr>
	</tbody>
</table>

protocol for relative hydrodynamic assessment of tri-leaflet polymer valves

目前可用的人工心脏瓣膜，异种移植，同种的限制，在该地区的三单张聚合物瓣膜的发展已经促使近期回潮。然而，聚合物阀流体动力学功能的初步评估鉴定的协议是至关重要的设计过程的早期阶段。传统体外脉冲复印机系统未配置，以适应灵活的三单张材料，此外，本地和人工心脏瓣膜，在相同的测试条件下，在一个相对的情况下需要作出评估聚合物阀功能，使测量过程中从不同的变异工具是可以避免的。因此，我们进行了水动力评估的i）本地（n = 4时，平均直径D = 20毫米），二）双向单张机械（N = 2，D = 23毫米）和iii）聚合物阀门组（n = 5， D = 22毫米），通过使用市售的脉冲复制器系统（ViVitro实验室公司，维多利亚，不列颠哥伦比亚省）的修改，以适应三单张阀门的几何形状。在佛罗里达大学开发的三单张硅阀，包括聚合物阀门组。甲中的比例为35:65的甘油与水的混合物被用来模仿血液物理性质。瞬时流量计量的左心室和主动脉单位的接口，而的压力录得的心室和主动脉的位置。双性恋单张及当地阀门从文献资料是用来验证的流量和压力读数。下面的水动力指标进行了报道:正向流量压力下降，主动脉根部的意思是方正向流量，主动脉瓣关闭，泄漏量返流，收盘transaortic，渗漏，总能量损失。代表结果表明，动力指标从三个阀门组能够成功地将组装成一个定制的市售脉冲复印机系统和subsequentlY，客观地比较提供聚合物阀设计，功能方面的见解。

代表的流量和压力波形示于图3，图4和5。在样本大小的地块，平均每个组的测试，这是阀门中，n = 5，4，2阀的聚合物，天然猪和双向单张组，分别。列于表1中的平均流体力学度量和这些样本的大小的平均值的标准误差。 <img alt="图1" src="/files/ftp_upload/50335/50335fig1.jpg" /> 图1。 （一）实施的Windkessel模型有关生理流量（这里提出的数字许可从ViVitro系统公司，BC，加拿大）的主要组成部分的ViVitro脉冲复印机系统示意图 。 （二）快速原型阀支架配置缝合和硅树脂或天然猪阀就地固定。 （三）Modificat离子ViVitro搏动循环容纳三单张阀的结构。 <a href="https://www.jove.com/files/ftp_upload/50335/50335fig1large.jpg" target="_blank">点击这里查看大图</a> 。 <img alt="图2" src="/files/ftp_upload/50335/50335fig2.jpg" /> 图2。 （一）原住民猪阀的。 （二）聚合物瓣叶顶视图。 （三）侧视图聚合物阀后缝合和固定在阀支架内。 （四）"圣裘德双向单张机械阀。 <a href="https://www.jove.com/files/ftp_upload/50335/50335fig2large.jpg" target="_blank">点击这里查看大图</a> 。 <img alt="图3" src="/files/ftp_upload/50335/50335fig3.jpg" /> 图3。平均瞬时流量的3个阀门测试组（n = 5，4，2阀聚合物，天然猪<html> D双向单张，分别）。心室和主动脉腔（ 见图1a）的接口位置放置在一种非侵入性的流量探头连接到使用电磁流量计测量流量， <a href="https://www.jove.com/files/ftp_upload/50335/50335fig3large.jpg" target="_blank">点击这里查看大图</a> 。 <img alt="图4" src="/files/ftp_upload/50335/50335fig4.jpg" /> 图4。平均瞬时心室压力测试的3个阀门组（n = 5，4，2气门聚合物，天然猪和双向单张，分别 ）。在脑室腔，采用微尖的压力换能器测定左心室压力。叠加文学心室压力的本地和双向单张阀（直径:29毫米），分别从18和19。fig4large.jpg"目标="_blank"&gt;点击这里查看大图。 <img alt="图5" src="/files/ftp_upload/50335/50335fig5.jpg" /> 图5。瞬时平均动脉压的3阀测试组（n = 5，4和2个阀的高分子，天然猪和双向单张）。下游距主动脉瓣的位置，采用微尖的压力换能器测定动脉压。从18日和19日 ，分别获得叠加文献主动脉压文献值本地和双向单张（直径:29毫米）阀门， <a href="https://www.jove.com/files/ftp_upload/50335/50335fig5large.jpg" target="_blank">点击这里查看大图</a> 。 <table border="1"><tbody><tr><td></td><td colspan="2"> 双向单张组（n = 2） </td><td colspan="2"> （聚合物5例） </td><td colspan="2"> 猪组（n = 4） </s豪华型&gt; </td></tr><tr><td> 数据说明 </td><td> 意味着 </td><td> SEM </td><td> 意味着 </td><td> SEM </td><td> 意味着 </td><td> SEM </td></tr><tr><td>主动脉瓣口面积[P]（厘米2） </td><td> 3.143 </td><td> 2.697 </td><td> 2.920 </td><td> 1.306 </td><td> 2.516 </td><td> 1.258 </td></tr><tr><td>主动脉瓣口面积[F]（2） </td><td> 7.940 </td><td> 1.286 </td><td> 4.613 </td><td> 2.063 </td><td> 3.975 </td><td> 1.988 </td></tr><tr><td>主动脉瓣口面积[H]（厘米2） </td><td> 7.516 </td><td> 1.633 </td><td> 4.575 </td><td> 2.046 </td><td> 3.942 </td><td> 1.971 </td></tr><tr><td>正向流量压降[P]（毫米汞柱） </td><td> 17.000 </td><td> 0.054 </td><td> 22.284 </td><td> 12.007 </td><td> 40.795 </td><td> 11.670 </td></tr><tr><tD&gt;转发流量压降[F]（毫米汞柱） </td><td> 0.410 </td><td> 0.210 </td><td> 30.424 </td><td> 9.235 </td><td> 29.766 </td><td> 9.733 </td></tr><tr><td>正向流量压降[H]（毫米汞柱） </td><td> 26.520 </td><td> 0.120 </td><td> 50.790 </td><td> 4.230 </td><td> 5.610 </td><td> 4.970 </td></tr><tr><td>跨主动脉最大压力（毫米汞柱） </td><td> 15.850 </td><td> 12.400 </td><td> 60.930 </td><td> 20.470 </td><td> 75.250 </td><td> 17.470 </td></tr><tr><td>主动脉RMS正向流量[P]（毫升/秒） </td><td> 88.280 </td><td> 11.110 </td><td> 162.120 </td><td> 24.970 </td><td> 189.080 </td><td> 32.610 </td></tr><tr><td>主动脉RMS正向流量[F]（毫升/秒） </td><td> 193.570 </td><td> 3.820 </td><td> 204.560 </td><td> 6.680 </td><td> 177.310 </td><td> 2.630 </td></tr><tr><td>主动脉RMS正向流量[H]（毫升/秒） </td><td> 197.790 </td><td> 0.630 </td><td> 174.760 </td><td> 11.530 </td><td> 182.680 </td><td> 3.160 </td></tr><tr><td>主动脉正向量（毫升） </td><td> 68.180 </td><td> 6.430 </td><td> 55.390 </td><td> 3.660 </td><td> 64.200 </td><td> 1.750 </td></tr><tr><td>主动脉闭合容积（毫升） </td><td> 62.260 </td><td> 0.860 </td><td> 32.990 </td><td> 9.820 </td><td> 45.260 </td><td> 11.990 </td></tr><tr><td>主动脉泄漏量（毫升） </td><td> 60.140 </td><td> 3.470 </td><td> 33.090 </td><td> 9.220 </td><td> 56.130 </td><td> 11.260 </td></tr><tr><td>反流总容量（ml） </td><td> 122.400 </td><td> 4.320 </td><td> 66.080 </td><td> 17.200 </td><td> 101.390 </td><td> 23.160 </td></tr><tr><td> TransAortic正向流动能量损耗（MJ） </td><td> 80.321 </td><td> 4.65 </td><td> 115.287 </td><td> 17.354 </td><td> 184.325 </td><td> 12.354 </td></tr><tr><td> TransAortic截止能量损耗（MJ） </td><td> 25.231 </td><td> 0。589 </td><td> 29.52 </td><td> 6.872 </td><td> 12.354 </td><td> 4.874 </td></tr><tr><td>漏TransAortic能源损耗（MJ） </td><td> 87.219 </td><td> 13.242 </td><td> 84.02 </td><td> 12.205 </td><td> 97.029 </td><td> 25.047 </td></tr><tr><td>总能量损失TransAortic（​​MJ） </td><td> 192.771 </td><td> 23.51 </td><td> 228.827 </td><td> 47.254 </td><td> 293.708 </td><td> 36.483 </td></tr></tbody></table> 表1（SEM）的平均水动力指标为测试心脏瓣膜计算的均值和标准差（N = 5，4，和2阀聚合物，天然猪和双向单张，分别）。应注意以下间隔:P:间隔开始和结束0 TVP，F:正向流量和H间隔:间隔开始与TVP 0和0流结束。阀的平均直径如下:聚合物阀组（n = 5）:22毫米;原住民猪阀组（n = 4）:20毫米;I-单张组（n = 2）:23毫米。小样本大小为双向单张阀由于有限样本供研究使用;两个双向单张阀门测试先前捐赠给佛罗里达国际大学由圣犹达医疗用品（圣保罗，明尼苏达州）的生物医学工程系。

Watch this Scientific Journal Video about Protocol for Relative Hydrodynamic Assessment of Tri-leaflet Polymer Valves at JoVE.com

Protocol for Relative Hydrodynamic Assessment of Tri-leaflet Polymer Valves

已续期开发聚合物阀门的兴趣。这里，目的是为了证明修改一个商业脉冲复印机的可行性，容纳三单张几何定义一个协议，目前聚合物阀流体动力学数据，在本地和人工瓣膜在近乎相同的条件下收集的数据相比。

协议相对液力评估的三单张聚合物阀

Limitations of currently available prosthetic valves, xenografts, and homografts have prompted a recent resurgence of developments in the area of ...

protocol-for-relative-hydrodynamic-assessment-tri-leaflet-polymer

Universidad San Sebastian

Research

JoVE Journal

Bioengineering

13.7K 次观看.  Florida International University. 已续期开发聚合物阀门的兴趣。这里，目的是为了证明修改一个商业脉冲复印机的可行性，容纳三单张几何定义一个协议，目前聚合物阀流体动力学数据，在本地和人工瓣膜在近乎相同的条件下收集的数据相比。

视频: Protocol for Relative Hydrodynamic Assessment of Tri-leaflet Polymer Valves

Design of a Cyclic Pressure Bioreactor for the Ex Vivo Study of Aortic Heart Valves

The aortic valve, located between the left ventricle and the aorta, allows for unidirectional blood flow, preventing backflow into the ventricle. Aortic valve leaflets are composed of interstitial cells suspended within an extracellular matrix (ECM) and are lined with an endothelial cell monolayer. The valve withstands a harsh, dynamic environment and is constantly exposed to shear, flexion, tension, and compression. Research has shown calcific lesions in diseased valves occur in areas of high mechanical stress as a result of endothelial disruption or interstitial matrix damage1-3. Hence, it is not surprising that epidemiological studies have shown high blood pressure to be a leading risk factor in the onset of aortic valve disease4. 
The only treatment option currently available for valve disease is surgical replacement of the diseased valve with a bioprosthetic or mechanical valve5. Improved understanding of valve biology in response to physical stresses would help elucidate the mechanisms of valve pathogenesis. In turn, this could help in the development of non-invasive therapies such as pharmaceutical intervention or prevention. Several bioreactors have been previously developed to study the mechanobiology of native or engineered heart valves6-9. Pulsatile bioreactors have also been developed to study a range of tissues including cartilage10, bone11 and bladder12. The aim of this work was to develop a cyclic pressure system that could be used to elucidate the biological response of aortic valve leaflets to increased pressure loads. 
The system consisted of an acrylic chamber in which to place samples and produce cyclic pressure, viton diaphragm solenoid valves to control the timing of the pressure cycle, and a computer to control electrical devices. The pressure was monitored using a pressure transducer, and the signal was conditioned using a load cell conditioner. A LabVIEW program regulated the pressure using an analog device to pump compressed air into the system at the appropriate rate. The system mimicked the dynamic transvalvular pressure levels associated with the aortic valve; a saw tooth wave produced a gradual increase in pressure, typical of the transvalvular pressure gradient that is present across the valve during diastole, followed by a sharp pressure drop depicting valve opening in systole. The LabVIEW program allowed users to control the magnitude and frequency of cyclic pressure. The system was able to subject tissue samples to physiological and pathological pressure conditions. This device can be used to increase our understanding of how heart valves respond to changes in the local mechanical environment.

Design of a Cyclic Pressure Bioreactor for the Ex Vivo Study of Aortic Heart Valves

A cyclic pressure bioreactor capable of subjecting heart valve tissue to physiological and pathological pressure conditions has been designed. A LabVIEW program allows users to control pressure magnitude, amplitude and frequency. This device can be used to study the mechanobiology of heart valve tissue or isolated cells.

循环压力为生物反应器的设计体外主动脉心脏瓣膜的研究

The aortic valve, located between the left ventricle and the aorta, allows for unidirectional blood flow, preventing backflow into the ventricle. Aortic ...

科研

生物工程

A Chitosan Based, Laser Activated Thin Film Surgical Adhesive, 'SurgiLux': Preparation and Demonstration

Sutures are a 4,000 year old technology that remain the 'gold-standard' for wound closure by virtue of their repair strength (~100 KPa). However, sutures can act as a nidus for infection and in many procedures are unable to effect wound repair or interfere with functional tissue regeneration.1 Surgical glues and adhesives, such as those based on fibrin and cyanoacrylates, have been developed as alternatives to sutures for the repair of such wounds. However, current commercial adhesives also have significant disadvantages, ranging from viral and prion transfer and a lack of repair strength as with the fibrin glues, to tissue toxicity and a lack of biocompatibility for the cyanoacrylate based adhesives. Furthermore, currently available surgical adhesives tend to be gel-based and can have extended curing times which limit their application.2 Similarly, the use of UV lasers to facilitate cross-linking mechanisms in protein-based or albumin 'solders' can lead to DNA damage while laser tissue welding (LTW) predisposes thermal damage to tissues.3 Despite their disadvantages, adhesives and LTW have captured approximately 30% of the wound closure market reported to be in excess of US $5 billion per annum, a significant testament to the need for sutureless technology.4
In the pursuit of sutureless technology we have utilized chitosan as a biomaterial for the development of a flexible, thin film, laser-activated surgical adhesive termed 'SurgiLux'. This novel bioadhesive uses a unique combination of biomaterials and photonics that are FDA approved and successfully used in a variety of biomedical applications and products. SurgiLux overcomes all the disadvantages associated with sutures and current surgical adhesives (see Table 1).
In this presentation we report the relatively simple protocol for the fabrication of SurgiLux and demonstrate its laser activation and tissue weld strength. SurgiLux films adhere to collagenous tissue without chemical modification such as cross-linking and through irradiation using a comparatively low-powered (120 mW) infrared laser instead of UV light. Chitosan films have a natural but weak adhesive attraction to collagen (~3 KPa), laser activation of the chitosan based SurgiLux films emphasizes the strength of this adhesion through polymer chain interactions as a consequence of transient thermal expansion.5 Without this 'activation' process, SurgiLux films are readily removed.6-9 SurgiLux has been tested both in vitro and in vivo on a variety of tissues including nerve, intestine, dura mater and cornea. In all cases it demonstrated good biocompatibility and negligible thermal damage as a consequence of irradiation.6-10

A Chitosan Based, Laser Activated Thin Film Surgical Adhesive, &#039;SurgiLux&#039;: Preparation and Demonstration

The fabrication of a novel, flexible thin film surgical adhesive from FDA approved ingredients, chitosan and indocyanine green is described. Bonding of this adhesive to collagenous tissue through a simple activation process with a low-powered infra-red laser is demonstrated.

基于几丁聚糖，激光激发薄膜手术胶粘剂，"SurgiLux的制备及示范

Sutures are a 4,000 year old technology that remain the 'gold-standard' for wound closure by virtue of their repair strength (~100 KPa). However, sutures ...

Polymer Microarrays for High Throughput Discovery of Biomaterials

The discovery of novel biomaterials that are optimized for a specific biological application is readily achieved using polymer microarrays, which allows a combinatorial library of materials to be screened in a parallel, high throughput format1. Herein is described the formation and characterization of a polymer microarray using an on-chip photopolymerization technique 2. This involves mixing monomers at varied ratios to produce a library of monomer solutions, transferring the solution to a glass slide format using a robotic printing device and curing with UV irradiation. This format is readily amenable to many biological assays, including stem cell attachment and proliferation, cell sorting and low bacterial adhesion, allowing the ready identification of 'hit' materials that fulfill a specific biological criterion3-5. Furthermore, the use of high throughput surface characterization (HTSC) allows the biological performance to be correlated with physio-chemical properties, hence elucidating the biological-material interaction6. HTSC makes use of water contact angle (WCA) measurements, atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS). In particular, ToF-SIMS provides a chemically rich analysis of the sample that can be used to correlate the cell response with a molecular moiety. In some cases, the biological performance can be predicted from the ToF-SIMS spectra, demonstrating the chemical dependence of a biological-material interaction, and informing the development of hit materials5,3.

A description of the formation of a polymer microarray using an on-chip photopolymerization technique. The high throughput surface characterization using atomic force microscopy, water contact angle measurements, X-ray photoelectron spectroscopy and time of flight secondary ion mass spectrometry and a cell attachment assay is also described.

聚合物芯片高通量发现的生物材料

The discovery of novel biomaterials that are optimized for a specific biological application is readily achieved using polymer microarrays, which allows a ...

Environmentally-controlled Microtensile Testing of Mechanically-adaptive Polymer Nanocomposites for ex vivo Characterization

Implantable microdevices are gaining significant attention for several biomedical applications1-4. Such devices have been made from a range of materials, each offering its own advantages and shortcomings5,6. Most prominently, due to the microscale device dimensions, a high modulus is required to facilitate implantation into living tissue. Conversely, the stiffness of the device should match the surrounding tissue to minimize induced local strain7-9. Therefore, we recently developed a new class of bio-inspired materials to meet these requirements by responding to environmental stimuli with a change in mechanical properties10-14. Specifically, our poly(vinyl acetate)-based nanocomposite (PVAc-NC) displays a reduction in stiffness when exposed to water and elevated temperatures (e.g. body temperature). Unfortunately, few methods exist to quantify the stiffness of materials in vivo15, and mechanical testing outside of the physiological environment often requires large samples inappropriate for implantation. Further, stimuli-responsive materials may quickly recover their initial stiffness after explantation. Therefore, we have developed a method by which the mechanical properties of implanted microsamples can be measured ex vivo, with simulated physiological conditions maintained using moisture and temperature control13,16,17. 
To this end, a custom microtensile tester was designed to accommodate microscale samples13,17 with widely-varying Young's moduli (range of 10 MPa to 5 GPa). As our interests are in the application of PVAc-NC as a biologically-adaptable neural probe substrate, a tool capable of mechanical characterization of samples at the microscale was necessary. This tool was adapted to provide humidity and temperature control, which minimized sample drying and cooling17. As a result, the mechanical characteristics of the explanted sample closely reflect those of the sample just prior to explantation.
The overall goal of this method is to quantitatively assess the in vivo mechanical properties, specifically the Young's modulus, of stimuli-responsive, mechanically-adaptive polymer-based materials. This is accomplished by first establishing the environmental conditions that will minimize a change in sample mechanical properties after explantation without contributing to a reduction in stiffness independent of that resulting from implantation. Samples are then prepared for implantation, handling, and testing (Figure 1A). Each sample is implanted into the cerebral cortex of rats, which is represented here as an explanted rat brain, for a specified duration (Figure 1B). At this point, the sample is explanted and immediately loaded into the microtensile tester, and then subjected to tensile testing (Figure 1C). Subsequent data analysis provides insight into the mechanical behavior of these innovative materials in the environment of the cerebral cortex.

Environmentally-controlled Microtensile Testing of Mechanically-adaptive Polymer Nanocomposites for ex vivo Characterization

A method is discussed by which the in vivo mechanical behavior of stimuli-responsive materials is monitored as a function of time. Samples are tested ex vivo using a microtensile tester with environmental controls to simulate the physiological environment. This work further promotes understanding the in vivo behavior of our material.

环境控制机械自适应聚合物纳米复合材料的微拉伸测试<em&gt;体外</em&gt;表征

Implantable microdevices are gaining significant attention for several biomedical applications1-4. Such devices have been made from a range of materials, ...

Intra-lymph Node Injection of Biodegradable Polymer Particles

Generation of adaptive immune response relies on efficient drainage or trafficking of antigen to lymph nodes for processing and presentation of these foreign molecules to T and B lymphocytes. Lymph nodes have thus become critical targets for new vaccines and immunotherapies. A recent strategy for targeting these tissues is direct lymph node injection of soluble vaccine components, and clinical trials involving this technique have been promising. Several biomaterial strategies have also been investigated to improve lymph node targeting, for example, tuning particle size for optimal drainage of biomaterial vaccine particles. In this paper we present a new method that combines direct lymph node injection with biodegradable polymer particles that can be laden with antigen, adjuvant, or other vaccine components. In this method polymeric microparticles or nanoparticles are synthesized by a modified double emulsion protocol incorporating lipid stabilizers. Particle properties (e.g.&#160;size, cargo loading) are confirmed by laser diffraction and fluorescent microscopy, respectively. Mouse lymph nodes are then identified by peripheral injection of a nontoxic tracer dye that allows visualization of the target injection site and subsequent deposition of polymer particles in lymph nodes. This technique allows direct control over the doses and combinations of biomaterials and vaccine components delivered to lymph nodes and could be harnessed in the development of new biomaterial-based vaccines.

Lymph nodes are the immunological tissues that orchestrate immune response and are a critical target for vaccines. Biomaterials have been employed to better target lymph nodes and to control delivery of antigens or adjuvants. This paper describes a technique combining these ideas to inject biocompatible polymer particles into lymph nodes.

可生物降解聚合物颗粒的淋巴内结注射

Generation of adaptive immune response relies on efficient drainage or trafficking of antigen to lymph nodes for processing and presentation of these ...

Manufacturing Of Robust Natural Fiber Preforms Utilizing Bacterial Cellulose as Binder

A novel method of manufacturing rigid and robust natural fiber preforms is presented here. This method is based on a papermaking process, whereby loose and short sisal fibers are dispersed into a water suspension containing bacterial cellulose. The fiber and nanocellulose suspension is then filtered (using vacuum or gravity) and the wet filter cake pressed to squeeze out any excess water, followed by a drying step. This will result in the hornification of the bacterial cellulose network, holding the loose natural fibers together.
Our method is specially suited for the manufacturing of rigid and robust preforms of hydrophilic fibers. The porous and hydrophilic nature of such fibers results in significant water uptake, drawing in the bacterial cellulose dispersed in the suspension. The bacterial cellulose will then be filtered against the surface of these fibers, forming a bacterial cellulose coating. When the loose fiber-bacterial cellulose suspension is filtered and dried, the adjacent bacterial cellulose forms a network and hornified to hold the otherwise loose fibers together.
The introduction of bacterial cellulose into the preform resulted in a significant increase of the mechanical properties of the fiber preforms. This can be attributed to the high stiffness and strength of the bacterial cellulose network. With this preform, renewable high performance hierarchical composites can also be manufactured by using conventional composite production methods, such as resin film infusion (RFI) or resin transfer molding (RTM). Here, we also describe the manufacturing of renewable hierarchical composites using double bag vacuum assisted resin infusion.

We present a novel method of manufacturing rigid and robust short natural fiber preforms using a papermaking process. Bacterial cellulose acts simultaneously as the binder for the loose fibers and provides rigidity to the fiber preforms. These preforms can be infused with a resin to produce truly green hierarchical composites.

制造业的鲁棒天然纤维预制体的利用细菌纤维素为粘结剂

A novel method of manufacturing rigid and robust natural fiber preforms is presented here. This method is based on a papermaking process, whereby loose ...

Culturing Mouse Cardiac Valves in the Miniature Tissue Culture System

Heart valve disease is a major burden in the Western world and no effective treatment is available. This is mainly due to a lack of knowledge of the molecular, cellular and mechanical mechanisms underlying the maintenance and/or loss of the valvular structure. 
Current models used to study valvular biology include in vitro cultures of valvular endothelial and interstitial cells. Although, in vitro culturing models provide both cellular and molecular mechanisms, the mechanisms involved in the 3D-organization of the valve remain unclear. While in vivo models have provided insight into the molecular mechanisms underlying valvular development, insight into adult valvular biology is still elusive. 
In order to be able to study the regulation of the valvular 3D-organization on tissue, cellular and molecular levels, we have developed the Miniature Tissue Culture System. In this ex vivo flow model the mitral or the aortic valve is cultured in its natural position in the heart. The natural configuration and composition of the leaflet are maintained allowing the most natural response of the valvular cells to stimuli. The valves remain viable and are responsive to changing environmental conditions. This MTCS may provide advantages on studying questions including but not limited to, how does the 3D organization affect valvular biology, what factors affect 3D organization of the valve, and which network of signaling pathways regulates the 3D organization of the valve.

Here, we present an ex vivo flow model in which murine cardiac valves can be cultured allowing the study of the biology of the valve.

在小型组织培养体系培养老鼠心脏瓣膜

Heart valve disease is a major burden in the Western world and no effective treatment is available. This is mainly due to a lack of knowledge of the ...

Film Extrusion of Crambe abyssinica/Wheat Gluten Blends

Crambe abyssinica is a plant with potential for use in industrial (non-food) plant oil production. The side stream from this oil production is a high-protein crambe meal that has limited value, as it is not fit for food or feed use. However, it contains proteins that could potentially make it a suitable raw material for higher-value products. The purpose of this study was to find methods of making this side stream into extruded films, showing that products with a higher value can be produced. The study mainly considered the development of material compositions and methods of preparing and extruding the material. Wheat gluten was added as a supportive protein matrix material, together with glycerol as a plasticizer and urea as a denaturant. The extrudate was evaluated with respect to mechanical (tensile testing) and oxygen barrier properties, and the extrudate structure was revealed visually and by scanning electron microscopy. A denser, more homogeneous material had a lower oxygen transmission rate, higher strength, and higher extensibility. The most homogeneous films were made at an extruder die temperature of 125-130 &#176;C. It is shown here that a film can be extruded with promising mechanical and oxygen barrier properties, the latter especially after a final compression molding step.

Film Extrusion of Crambe abyssinica/Wheat Gluten Blends

The side stream from plant oil production of Crambe abyssinica has limited value. The purpose of this study was to find methods for extruding materials based on this side stream, demonstrating that products with a higher value can be produced. The extrudates were found to have promising properties.

薄膜挤出<em&gt;海甘蓝abyssinica</em&gt; /谷朊粉共混物

Crambe abyssinica is a plant with potential for use in industrial (non-food) plant oil production. The side stream from this oil production is a ...

Melt Electrospinning Writing of Three-dimensional Poly(&#949;-caprolactone) Scaffolds with Controllable Morphologies for Tissue Engineering Applications

This tutorial reflects on the fundamental principles and guidelines for electrospinning writing with polymer melts, an additive manufacturing technology with great potential for biomedical applications. The technique facilitates the direct deposition of biocompatible polymer fibers to fabricate well-ordered scaffolds in the sub-micron to micro scale range. The establishment of a stable, viscoelastic, polymer jet between a spinneret and a collector is achieved using an applied voltage and can be direct-written. A significant benefit of a typical porous scaffold is a high surface-to-volume ratio which provides increased effective adhesion sites for cell attachment and growth. Controlling the printing process by fine-tuning the system parameters enables high reproducibility in the quality of the printed scaffolds. It also provides a flexible manufacturing platform for users to tailor the morphological structures of the scaffolds to their specific requirements. For this purpose, we present a protocol to obtain different fiber diameters using melt electrospinning writing (MEW) with a guided amendment of the parameters, including flow rate, voltage and collection speed. Furthermore, we demonstrate how to optimize the jet, discuss often experienced technical challenges, explain troubleshooting techniques and showcase a wide range of printable scaffold architectures.

Melt Electrospinning Writing of Three-dimensional Poly(&amp;#949;-caprolactone) Scaffolds with Controllable Morphologies for Tissue Engineering Applications

This protocol serves as a comprehensive guideline to fabricate scaffolds via electrospinning with polymer melts in a direct writing mode. We systematically outline the process and define the appropriate parameter settings for achieving targeted scaffold architectures.

用于组织工程应用的三维聚 (ε-内) 支架的熔体静电纺丝

This tutorial reflects on the fundamental principles and guidelines for electrospinning writing with polymer melts, an additive manufacturing technology ...

Synthesis of Functionalized 10-nm Polymer-coated Gold Particles for Endothelium Targeting and Drug Delivery

Gold nanoparticles (AuNPs) have been used extensively in medical research due to their size, biocompatibility, and modifiable surface. Specific targeting and drug delivery are some of the applications of these AuNPs, but endothelial extracellular matrices&#39; defensive properties hamper particle uptake. To address this issue, we describe a synthesis method for ultrasmall gold nanoparticles to improve vascular delivery, with customizable functional groups and polymer lengths for further adjustments. The protocol yields 2.5 nm AuNPs that are capped with tetrakis(hydroxymethyl)phosphonium chloride (THPC). The replacement of THPC with hetero-functional polyethylene glycol (PEG) on the surface of the AuNP increases the hydrodynamic radius to 10.5 nm while providing various functional groups on the surface. The last part of the protocol includes an optional addition of a fluorophore to allow the AuNPs to be visualized under fluorescence to track nanoparticle uptake. Dialysis and lyophilization were used to purify and isolate the AuNPs. These fluorescent nanoparticles can be visualized in both in vitro and in vivo experiments due to the biocompatible PEG coating and fluorescent probes. Additionally, the size range of these nanoparticles render them an ideal candidate for probing the glycocalyx without disrupting normal vasculature function, which may lead to improved delivery and therapeutics.

We describe a method of synthesizing biocompatible 10-nm gold nanoparticles, functionalized by coating poly-ethylene glycol onto the surface. These particles can be used in vitro and in vivo for delivering therapeutics to nanoscale cellular and extracellular spaces that are difficult to access with conventional nanoparticle sizes.

用于内皮靶向和药物传递的功能化10纳米高分子涂层金粒子的合成

Gold nanoparticles (AuNPs) have been used extensively in medical research due to their size, biocompatibility, and modifiable surface. Specific targeting ...