作者感谢 Scanley 博士为她的技术培训和帮助使用 TEM 在康涅狄格州立大学 (CSCU) 纳米技术中心和 Ishita 博士 Mukerji 在卫斯理大学访问她的 CD分 光 光度计。所报告的工作部分是在美国宇航局康涅狄格州空间赠款联合会的费尔菲尔德大学科学研究所和国家科学基金会 CHE-1624774 的资助下进行的。

1. 12-Dithiolane 改性肽的合成与纯化
<ol><li>dithiolane 前体的合成, 3-(acetylthio)-2-(acetylthiomethyl) 丙酸19。
	<ol>
<li>添加1克 3-溴-2-(溴甲基) 丙酸 (1 equiv) 溶解在极小量的1米氢氧化钠 (约4毫升) 到一个25毫升的圆形底部反应瓶搅拌在55摄氏度。在氮气气氛下, 将反应瓶密封在一个隔膜和地方。</li>
		<li>在4毫升的去离子水和3毫升的2米硫酸 (H2,4) 中, 制备含有1.49 克硫代乙酸钾 (3.2 equiv) 的溶液,在原位制造硫代乙酸酸。</li>
		<li>将硫代乙酸酸溶液拉入塑料一次性10毫升注射器, 并将针头放在注射器上。将混合物滴状到反应瓶中, 用针穿透隔膜。继续反应过夜在55摄氏度。</li>
		<li>用甲醇和二氯甲烷混合物 (1:9) 对硅胶 60 F254板上的薄层层析 (TLC) 进行反应。通过甲酚绿色染色可视化反应过程。该产品有 Rf = 0.57。</li>
		<li>在反应完成并且冷却了到室温之后, 酸化混合物到 pH 值1与 2 M H2那么4。黄色的油从溶液中分离出来。</li>
		<li>用冷氯仿提取产品 (40 毫升 x 3)。将有机层和干燥的硫酸镁结合在一起。在减压下取出氯仿。</li>
		<li>通过核磁共振 (NMR) 光谱学 (如图 1B和C所示) 确认隔离产品1的身份。期望以下结果: 1h 核磁共振, CDCl3, 300 兆赫: d = 10.1 (b, 1 h), 3.2 (m, 4 h), 2.9 (m, 1 h), 2.4 (s, 6 h);13c 核磁共振, CDCl3, 75 兆赫: d = 195.1 (CH3COS-), 177.6 (-c哦), 45.1 (-ch2S), 30.5 (Ch), 29.2 (-上海合作组织Ch3)。 注: 该产品为黄油, 总收率为83%。使用该产品无需进一步净化。</li>
	</ol></li>
	<li>Dithiolane 前驱体的许可证与树脂耦合 注: 下面描述的固相肽合成是根据推荐的制造商的协议在自动肽合成器上进行的。设置和试剂可适用于其他商业仪器或使用专用氨基酸。<ol>
<li>在反应容器中称量0.156 克的溜冰场酰胺 4-methylbenzhydrylamine (MBHA) 树脂 (0.1 毫摩尔) 和位置。在合成开始前, 将树脂在甲基酰胺 (DMF) 中膨胀至少15分钟。</li>
		<li>将每个 fluorenylmethyloxycarbonyl (n-芴甲氧羰基) 受保护氨基酸 (0.4 毫摩尔) 的4当量与0.152 克n、n、n、n '-四甲基O(1Hbenotriazol 1 基) 铀六氟磷酸盐 (0.4 毫摩尔、HBTU) 进行权衡, 以序列中的每个氨基酸。每个墨盒都含有 n-芴甲氧羰基保护的氨基酸和 HBTU。</li>
		<li>在对合成器 (重新灌装试剂、冲洗试剂线和加压的所有试剂瓶) 进行所有预合成检查后, 将氨基酸盒放入 C ' 到 N ' 终点方向的旋转木马中。放置一个空墨盒后, 最终的氨基酸位置为最终 n-末端芴甲氧羰基脱步骤。</li>
		<li>使用标准推荐设置合成肽。<ol>
<li>Deprotect 甲氧羰基基团从树脂与5毫升20% 哌啶在 DMF (5 分钟 x 2)。</li>
			<li>在联轴器步骤前, 用 DMF (6 x 5 毫升) 清洗树脂。</li>
			<li>对于单一的耦合步骤, 在 DMF 中加入4毫升的0.4 米 n-甲基啉) 到 n-芴甲氧羰基保护的氨基酸和 HBTU。在将溶液转移到反应容器之前, 激活三十年代的芴甲氧羰基保护氨基酸溶液。 注: 自动肽合成器混合树脂和解决方案通过冒泡 N2气体每三十年代20分钟, 而耦合反应发生的地方。对于人工肽合成, 在耦合步骤的持续时间内, 将反应容器以低速的速度放置在轨道振动筛上。</li>
			<li>排出溶液, 用 DMF (3 x 5 毫升) 清洗树脂。</li>
			<li>重复步骤1.2.4.1 通过1.2.4.4 的每一个 n-芴甲氧羰基保护氨基酸在 C ' 到 N '-终点方向合成的肽感兴趣。</li>
		</ol>
</li>
		<li>最后的 N 端脱步骤后, 将树脂转移到一次性烧结注射器中。用 DMF (3 x 5 毫升) 和二氯甲烷 (DCM, 3 x 5 毫升) 洗涤树脂。 注: 树脂可贮存后, 在真空干燥的 DCM 洗涤。如果树脂以前储存在联轴器上, 在偶联反应之前确保在 DMF 中膨胀树脂。</li>
		<li>将 dithiolane 前驱体 (1) 加入4当量1、5毫升 DMF、4当量的 HBTU 和10当量的 n、n-diisopropylethylamine (DIPEA), 对树脂肽的 N 端进行耦合。在加入含有烧结注射器的树脂之前, 先激活10分钟的耦合混合物。</li>
		<li>震动2小时的耦合反应。2小时后, 用 DMF (3 x 5 毫升) 清洗树脂, 并在一夜之间反复晃动耦合反应。</li>
		<li>第二联轴器后, 用 DMF (3 x 5 毫升) 和 DCM (3 x 5 毫升) 清洗树脂。 注 : 树脂可储存在真空下直至。</li>
	</ol></li>
	<li>树脂硫代乙酸脱和肽的裂解
	<ol>
<li>从 dithiolane 前驱体 deprotect 硫代乙酸组, 将干树脂转移到10毫升微波反应管中, 加入2毫升的 DMF。允许树脂膨胀, 加入一个小的磁力搅拌条到容器中, 并以低速磁搅拌的速度重新悬浮15分钟。</li>
		<li>加入2毫升的浓缩氢氧化铵, 将反应容器盖上硅胶隔膜, 将反应容器放入微波反应器中, 使用75°c 的微波设置, 搅拌45分钟。</li>
		<li>微波反应完成后, 将树脂转移到干净的一次性烧结注射器中。用 DMF (2 x 5 毫升) 和甲醇 (甲醇, 2 x 5 毫升) 洗涤。</li>
		<li>在甲醇 (1:4) 中加入浓缩氢氧化铵溶液, 总容积为5毫升。留在夜间摇晃, 以增加 dithiolane 环中二硫键的分子内氧化。</li>
		<li>用甲醇 (2 x 5 毫升) 和 DCM (3 x 5 毫升) 清洗树脂。 注: 干燥的树脂可以储存在真空干燥在这一点上。</li>
		<li>在含有注射器的树脂中加入裂解鸡尾酒, 轻轻摇动1.5 小时。所用的裂解鸡尾酒是95% 三氟乙酸酸 (TFA), 2.5% triisopropylsilane (提示), 2.5% 水在总容积5毫升。 注意事项: 仅在化学油烟机下工作。TFA 易挥发和腐蚀性。 注 : 对于多数肽序列和氨基酸边链保护组 , 上述鸡尾酒溶液是足够的 ;然而, 某些氨基酸侧链保护组 (特别是含有胱氨酸、满足、多党和 Arg 的多肽) 或其他树脂化学20可能需要替代的裂解鸡尾酒。</li>
		<li>将粗肽沉淀到25毫升的冷二乙基醚在50毫升圆锥管通过滴状添加从烧结注射器。肽沉淀成白色固体。以 1300 x g 为10分钟的离心法将该肽颗粒醒酒. 小心地将二乙基醚放入一个单独的容器中进行废物收集。</li>
		<li>再将25毫升乙醚加入锥形管, 再用涡流重新悬浮沉淀。重复离心在 1300 x g 10 分钟和醒酒二乙基醚再次。在真空下干燥颗粒。</li>
	</ol></li>
	<li>12-Dithiolane 改性肽的纯化 注: 采用反相高效相色谱法提纯粗肽。用 MALDI 质谱法采集和组合肽峰, 确认质量。<ol>
<li>用 0.1% TFA, 将微量的乙腈中的粗肽颗粒溶解。由于肽的疏水性和聚集倾向, 轻轻地加热样品在40°c, 以帮助溶解度。 注意: 避免更高的温度和超声波的肽, 以防止潜在的二硫化物交换反应21,22,23。</li>
		<li>为高效液相色谱纯化制备1毫升粗肽, 在乙腈中加入 400 ul 的浓缩肽库, 600 ul 为 H2O, 0.1% TFA, 通过22微米注射器过滤器将其过滤成 hplc 瓶。另外还可以添加5% 异丙醇, 以防止肽聚集和沉淀。</li>
		<li>用 C-18 半制备柱, 在15-55% 乙腈的线性梯度20分钟内, 用3毫升/分钟的流速纯化肽. 将紫外线探测器设置为 222 nm (酰胺骨干) 和 330 nm (二硫化物键)。收集并合并感兴趣的峰值 (图 2A)。</li>
		<li>在 reflectron 模式下, 通过 MALDI 质谱仪确认肽类产品质量 (图 2B)。为分析, 混合 0.5 ul 的收集峰值在 MALDI 板与 0.5 ul 25-苯甲酸酸 (DHB) 基质 (10 毫克/毫升 DHB 在50% 乙腈, 0.1% TFA)。 注: MALDI 质谱中常见的加合物包括钠和钾盐加合物 ([m + Na]+和 [m + K]+) 峰。如果盐加成峰抑制主 [米 + H]+峰值的信号, 则建议在分析之前对样品进行脱盐。此外, 在 12-dithiolane 修饰肽中也检测到 [M + O]+的氧化峰。利用 DHB 基质对激光诱导氧化的 MALDI 电离研究表明, 可以对样品浓度、溶剂和激光强度等因素进行修正, 以限制 MALDI 诱导氧化工件24。</li>
		<li>在 MALDI 确认正确质量后, lyophilize 在闪光冷冻后的肽。将冻干肽粉保持在真空下直至组装。</li>
	</ol></li>
</ol>2. 超分子自组装结构的表征
<ol><li>
淀粉样纤维的形成
	<ol>
<li>要准备自组装溶液, 用分析天平称量1毫克的肽粉。溶解成混合物 (pH 7.5) 的20% 乙腈和10毫米 (4-(2-羟乙基)-1-piperazineethanesulfonic 酸 (HEPES) 在1.5 毫升离心管, 最终浓度的1毫克/毫升肽组装混合物。涡流装配解决方案, 并在室温下组装。</li>
	</ol>
</li>
	<li>
淀粉样纤维的光谱表征
	<ol>
<li>通过傅里叶变换红外光谱 (FTIR), 每隔几天跟踪多肽组装过程。以1670厘米-1为中心的宽峰为样本17中未组装肽引起的 IR 特征。多肽组装样品通常需要一到两周的时间才能使宽未组装峰消失并达到成熟。<ol>
<li>干燥整除 8-10 ul 的组装解决方案作为一个薄膜上的 ATR 金刚石晶体。监测1640年至1630厘米-1的大型和宽水位的消失, 作为干膜形式。</li>
			<li>获取红外光谱从 1500-1800 cm-1平均50扫描与 2 cm-1决议。在每次采样扫描之前获取和减去背景扫描。β薄板组件的 IR 签名是介于1625和1635厘米-1 (图 3A)25、26之间的尖峰。</li>
		</ol>
</li>
		<li>用圆形二色谱 (CD) 表征多肽组装成β片丰富的超分子结构。使用 CD spectropolarimeter 与珀尔温度控制系统记录光谱。<ol>
<li>吸管 30 ul 的装配解决方案在0.1 毫米的路径长度 microcuvette。 注: 在仪器中, 需要一个电池架来夹紧和定位短路径长度单元格。</li>
			<li>对于每个频谱, 将 CD 仪器设置为以下参数: 扫描波长为 300 nm 到 180 nm, 扫描速率为 100/分钟, 波段宽度为 1 nm, 25 °c, 平均三扫描。</li>
			<li>收集缓冲区的频谱 (20% acetonitrile/10 mM HEPES, pH 值 7.5), 并减去每个样本扫描作为一个控制。β片的 CD 签名是一个椭圆的最小值, 其中心约为 220 nm (图 3B)27。</li>
		</ol>
</li>
	</ol>
</li>
	<li>
淀粉样纤维显微术
	<ol>
<li>允许三周的多肽样品成熟成β片丰富的超分子结构。 注: 在装配过程的早期阶段, 可以使用透射电镜 (TEM) 对组件进行成像。<ol>
<li>将肽组装溶液的 10 ul 在 TEM 碳网格表面上。 注意: 小心不要接触到网格表面的吸管尖端。在制备过程中, 采用高精度、自闭镊子来控制 TEM 网格。</li>
			<li>等待1-2 分钟, 以允许组件吸附到网格表面上。通过触摸滤纸到网格边缘, 删除多余的样品。</li>
			<li>通过将 100 ul 的去离子水添加到商业上4% 的醋酸盐溶液中, 制备出2% 的醋酸铀染色。吸管 10 ul 2% 的醋酸铀染色到网格表面和孵化2-3 分钟。孵化后, 通过触摸滤纸到网格边缘, 去除多余的污渍。</li>
			<li>将 TEM 网格放在真空干燥过夜。储存在真空下直到成像。</li>
			<li>用 TEM (图 3C) 对准备好的样品进行图像处理。显微镜的典型参数如下: 图像在放大范围从9,300X 到 23,000X, 钨灯丝与加速电压 120 kV。 注: ImageJ 可用于测量获得 TEM 图像的超分子结构的平均纤维宽度28。 警告: 使用前请查阅所有相关的安全数据表 (SDS)。所述 12-dithiolane 修饰自组装肽的合成、纯化和表征中使用的几种化学物质具有腐蚀性或毒性, 只应在化学油烟机下使用。在实验室工作时, 应始终使用适当的个人防护设备 (包括安全眼镜、实验室大衣、全长长裤、闭趾鞋)。</li>
		</ol>
</li>
	</ol>
</li>
</ol>

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E., Childers, W. S., Mehta, A. K., Lynn, D. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Kinetic+intermediates+in+amyloid+assembly.">Kinetic intermediates in amyloid assembly.</a> Journal of the American Chemical Society. 136, 15116-15149 (2014).</li><li>Smith, J. E., 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=Defining+the+dynamic+conformational+network+of+cross-&#946;+peptide+assembly.">Defining the dynamic conformational network of cross-&#946; peptide assembly.</a> Israel Journal of Chemistry. 55, 763-769 (2015).</li><li>Black, S. P., Sanders, J. K. M., Stefankiewicz, A. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Disulfide+exchange:+Exposing+supramolecular+reactivity+through+dynamic+covalent+chemistry.">Disulfide exchange: Exposing supramolecular reactivity through dynamic covalent chemistry.</a> Chemical Society Reviews. 43, 1861-1872 (2014).</li><li>Vendetti, A., 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=Dihydroasparagusic+acid:+Antioxidant+and+tyrosinase+inhibitory+activities+and+improved+synthesis.">Dihydroasparagusic acid: Antioxidant and tyrosinase inhibitory activities and improved synthesis.</a> Journal of Agricultural and Food Chemistry. 61, 6848-6855 (2013).</li><li>Stawikowski, M., Fields, G. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Introduction+to+peptide+synthesis.">Introduction to peptide synthesis.</a> Current Protocols in Protein Science. 26, (2002).</li><li>Canadell, J., Goossens, H., Klumperman, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Self-healing+materials+based+on+disulfide+links.">Self-healing materials based on disulfide links.</a> Macromolecules. 44, 2536-2541 (2011).</li><li>Lafont, U., van Zeijl, H., van der Zwaag, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Influence+of+cross-linkers+on+the+cohesive+and+adhesive+self-healing+ability+of+polydisulfide-based+thermosets.">Influence of cross-linkers on the cohesive and adhesive self-healing ability of polydisulfide-based thermosets.</a> ACS Applied Materials and Interfaces. 4, 6280-6288 (2012).</li><li>Komaromy, D., Stuart, M. C. A., Santiago, G. M., Tezcan, M., Krasnikov, V. V., Otto, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Self-assembly+can+direct+dynamic+covalent+bond+formation+toward+diversity+or+specificity.">Self-assembly can direct dynamic covalent bond formation toward diversity or specificity.</a> Journal of the American Chemical Society. 139, 6234-6241 (2017).</li><li>McAvery, K. M., Guan, B., Fortier, C. A., Tarr, M. A., Cole, R. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Laser-induced+oxidation+of+cholesterol+observed+during+MALDI-TOF+mass+spectrometry.">Laser-induced oxidation of cholesterol observed during MALDI-TOF mass spectrometry.</a> Journal of the American Society for Mass Spectrometry. 22, 659-669 (2011).</li><li>Krimm, S., Bandekar, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Vibrational+spectroscopy+and+conformation+of+peptides,+polypeptides,+and+proteins.">Vibrational spectroscopy and conformation of peptides, polypeptides, and proteins.</a> Advances in Protein Chemistry. 38, 181-364 (1986).</li><li>Halverson, K. J., Sucholeiki, I., Ashburn, T. T., Lansbury, P. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Location+of+&#946;-sheet-forming+sequences+in+amyloid+proteins+by+FTIR.">Location of &#946;-sheet-forming sequences in amyloid proteins by FTIR.</a> Journal of the American Chemical Society. 113, 6701-6703 (1991).</li><li>Greenfield, N., Fasman, G. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Computed+circular+dichroism+spectra+for+the+evaluation+of+protein+confirmation.">Computed circular dichroism spectra for the evaluation of protein confirmation.</a> Biochemistry. 8, 4108-4116 (1969).</li><li>. ImageJ Available from: <a target="_blank" href="https://imagej.nih.gov/ij">https://imagej.nih.gov/ij</a> (2016)</li><li>Roy, S., Shinde, S., Hamilton, G. A., Hartnett, H. E., Jones, A. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Artificial+[FeFe]-hydrogenase:+On+resin+modification+of+an+amino+acid+to+anchor+a+hexacarbonyldiiron+cluster+in+a+peptide+framework.">Artificial [FeFe]-hydrogenase: On resin modification of an amino acid to anchor a hexacarbonyldiiron cluster in a peptide framework.</a> European Journal of Inorganic Chemistry. 2011, 1050-1055 (2011).</li><li>Van Duinen, S. G., Castano, E. M., Prelli, F., Bots, G. T. A. 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作者没有什么可透露的。

本文讨论了 n-端 12-dithiolane 修饰自组装肽的合成和纯化的细节, 以及由此产生的超分子结构的特性。本报告所报道的 12-dithiolane 肽的合成具有优点, 包括一步法合成制备 dithiolane 前驱体、3-(acetylthio)-2-(acetylthiomethyl) 丙酸, 以及在树脂上微波脱反应的前体硫代乙酸保护基团, 利用氢氧化铵作为一种较安全的替代物, 脱29的毒性肼, 产生氧化的 12-dithiolane 基团。12-dithiolane 肽 (<strong class="x...

固相肽合成中的健壮肽键形成化学和控制序列长度和成分的能力使自组装成超分子结构的多肽成为一个研究领域。控制和稳定肽自组装结构的因素, 包括侧链空间和静电相互作用, 氢键和疏水效应1, 作为一套设计规则。随着对这些基本设计规则的研究继续进展, 肽自组装的逻辑下一步包括扩大肽基结构和功能的多样性。自组装多肽是一种多功能生物材料, 通过调整肽序列或装配条件2、3、4, 为许多医学应用而使用, 发展战略为对多肽纳米纤维5、6、7、8、9的组装后的修改仍然是一个相对未开发的领域。
超分子结构表面的动态二硫化物交换和硫醇化学是一个有潜力产生新的和功能性生物材料的领域。12-dithiolane 基团 (通常是硫辛酸 (la) 或 asparagusic 酸 (aa) 的衍生物) 在脂质体系统10、11、嵌段共聚物12、13和组织锚在表面14,15。在这里, 我们报告的合成和表征的自组装肽来源于与阿尔茨海默病相关的 Aβ肽的核核, 在 N 终点被修改 12-dithiolane 功能组16, 17。由此产生的超分子纤维作为实验平台, 研究了淀粉样纤维的超分子表面的二硫交换和硫醇反应性.18。

<table><tbody><tr><td>Rink amide MBHA resin, high load</td><td>Gyros Protein Technologies</td><td>RAM-5-HL</td><td>Avoid contact with skin and eyes; do not inhale</td></tr><tr><td>N,N-Dimethylformamide</td><td>Fisher Scientific</td><td>D119-4</td><td>Flammable liquid and vapor; irritating to eyes and skin; Use personal protective equipment; keep away from open flame</td></tr><tr><td>Fmoc-L-Val-OH</td><td>Gyros Protein Technologies</td><td>FLA-25-V</td><td>Wear personal protective equipment; do not inhale</td></tr><tr><td>Fmoc-L-Leu-OH</td><td>Gyros Protein Technologies</td><td>FLA-25-L</td><td>Wear personal protective equipment; do not inhale</td></tr><tr><td>Fmoc-L-Lys(Boc)-OH</td><td>Gyros Protein Technologies</td><td>FLA-25-KBC</td><td>Wear personal protective equipment; do not inhale</td></tr><tr><td>Fmoc-L-Phe-OH</td><td>Gyros Protein Technologies</td><td>FLA-25-F</td><td>Wear personal protective equipment; do not inhale</td></tr><tr><td>Fmoc-L-Ala-OH</td><td>Gyros Protein Technologies</td><td>FLA-25-A</td><td>Wear personal protective equipment; do not inhale</td></tr><tr><td>Fmoc-L-Gln(Trt)-OH</td><td>Gyros Protein Technologies</td><td>FLA-25-QT</td><td>Wear personal protective equipment; do not inhale</td></tr><tr><td>N,N,N&amp;prime;,N&amp;prime;-Tetramethyl-O-(1H-benzotriazol-1-yl)uronium hexafluorophosphate</td><td>Gyros Protein Technologies</td><td>26432</td><td>Causes skin, eye and respiratory irritation; do not inhale; use under hood or in well ventilated area</td></tr><tr><td>0.4 M N-methylmorpholine in DMF</td><td>Gyros Protein Technologies</td><td>PS3-MM-L</td><td>highly flammable; wear personal protective equipment; keep away from heat and keep container tightly closed; do not inhale or swallow; wash skin thoroughly after handling</td></tr><tr><td>20% piperidine in DMF</td><td>Gyros Protein Technologies</td><td>PS3-PPR-L</td><td>Causes severe eye and skin burns; Flammable Liquid and vapor; Do not inhale</td></tr><tr><td>dichloromethane</td><td>Fisher Scientific</td><td>D37-4</td><td>May cause cancer; Do not inhale; Wear personal protective equipment; use under hood only; if contacted rise with water for at least 15 minutes and obtain medical attention</td></tr><tr><td>acetonitrile</td><td>Fisher Scientific</td><td>A998-4</td><td>Flammable; irritating to eyes; Use personal protective equipment; Use only under a fume hood; keep away from open flame or hot surface; if contacted rinse wiith water for at least 15 minutes and obtain medical attention</td></tr><tr><td>trifluoroacetic acid</td><td>Fisher Scientific</td><td>A116-50</td><td>Causes severe burns; do not inhale; harmful to aquatic life; use personal protective equipment; use only under fume hood; if contacted rinse with water for at least 15 minutes and obain immediate medical attention</td></tr><tr><td>4% uranyl acetate</td><td>Electron Microscopy Sciences</td><td>22400-4</td><td>Do not inhale; harmful to aquatic life</td></tr><tr><td>4-(2-Hydroxyethyl)piperazine-1-ethanesulfonic acid</td><td>Acros Organics</td><td>AC172571000</td><td>Do not inhale; use outdoors or in well-ventilated area</td></tr><tr><td>nitrogen Gas</td><td>TechAir</td><td></td><td>Contents under pressure, may explode if heated</td></tr><tr><td>3-bromo-2-(bromomethyl)propionic acid</td><td>Alfa Aesar</td><td>AAA1963014</td><td>Do not inhale; causes irritation to skin and eyes; corrosive</td></tr><tr><td>sodium hydroxide</td><td>Fisher Scientific</td><td>S318-100</td><td>Use personal protective equipment; use only under fume hood; if contact rinse area for at least 15 minutes and obtain medical attention</td></tr><tr><td>potassium thioacetate</td><td>Acros Organics</td><td>AC221300250</td><td>Causes skin and eye irritation; do not inhale; use personal protective equipment</td></tr><tr><td>sulfuric acid</td><td>Fisher Scientific</td><td>SA213</td><td>Causes burns; keep away from water; keep away from combustible material; do not inhale; use personal protective equipment; if contact rinse area for at least 15 minutes and obtain medical attention</td></tr><tr><td>chloroform-d</td><td>Acros Organics</td><td>AC320690075</td><td>Possible cancer hazard; irritating to skin and eyes; do not inhale; Use personal protective equipment; use only under fume hood; If contact rinse area for at least 15 minutes and obtain medical attention</td></tr><tr><td>chloroform</td><td>Fisher Scientific</td><td>C298-4</td><td>Possible cancer hazard; irritating to skin and eyes; do not inhale; Use personal protective equipment; use only under fume hood; If contact rinse area for at least 15 minutes and obtain medical attention</td></tr><tr><td>N,N-diisopropylethylamine</td><td>Acros Organics</td><td>AC367841000</td><td>Highly flammable; harmful to aquatic life; wear personal protective equipment; do not swallow</td></tr><tr><td>ammonium hydroxide</td><td>Fisher Scientific</td><td>A669S-500</td><td>Corrosive; do not inhale</td></tr><tr><td>methanol</td><td>Fisher Scientific</td><td>A452-4</td><td>Flammable liquid and vapor; use personal protective equipment; do not inhale; If contact rinse area for at least 15 minutes and obtain medical attention</td></tr><tr><td>triisopropylsilane</td><td>Sigma Aldrich</td><td>233781</td><td>Flammable; use personal proctective safety equipment; keep container tightly closed</td></tr><tr><td>diethyl ether</td><td>Fisher Scientific</td><td>E138-1</td><td>Extremely flammable; Irritating to skin and eyes; Use personal protective equipment</td></tr><tr><td>2,5-dihydroxybenzoic acid</td><td>Sigma Aldrich</td><td>39319-10x10MG-F</td><td>do not inhale; irritating to skin and eyes</td></tr><tr><td>alpha-cyano-4-hydroxycinnamic acid</td><td>Alfa Aesar</td><td>AAJ67635EXK</td><td></td></tr><tr><td>c18 zip-tip</td><td>Millipore</td><td>ZTC18S096</td><td></td></tr><tr><td>tris(2-carboxyethyl) phospine hydrochloride</td><td>Thermo Scientific</td><td>PI20490</td><td></td></tr><tr><td>silica gel 60 F254 coated aluminum-backed TLC sheets</td><td>EMD Millipore</td><td>1.05549.0001</td><td></td></tr><tr><td>Thin walled Precision NMR tubes</td><td>Bel-Art</td><td>663000585</td><td>5mm O.D.</td></tr><tr><td>All-plastic Norm-Ject syringes</td><td>Air Tite</td><td>AL10</td><td></td></tr><tr><td>single-use needle</td><td>BD PrecisionGlide</td><td>BD 305185</td><td>used needles get disposed on in sharps waste container</td></tr><tr><td>disposable fritted syringe</td><td>Torviq</td><td>SF1000LL</td><td>10mL fritted syringes were used in the report, but larger syringes are avaibale if needed for larger scale synthesis.</td></tr><tr><td>carbon grid</td><td>Ted Pella, Inc.</td><td>CF200-CU</td><td>Make sure to prepare samples and staining on the carbon grid side, not the shiny copper side of grid</td></tr><tr><td>self-closing tweezers</td><td>Electron Microscopy Sciences</td><td>78318-3X</td><td>very sharp tips, length: 120 mm</td></tr><tr><td>0.1 mm short path length cell</td><td>Starna Cells, Inc.</td><td>20/C-Q-0.1</td><td>Fragile</td></tr><tr><td>10mL Vessel Caps</td><td>CEM</td><td>909210</td><td></td></tr><tr><td>10mL Pressure Vessels</td><td>CEM</td><td>908035</td><td></td></tr><tr><td>Aeris Semi-Prep HPLC column</td><td>Phenomenex</td><td>00F-4632-N0</td><td>150 x 10mm</td></tr><tr><td>cell holder</td><td>Starna Cells, Inc.</td><td>CH-2049</td><td>Needed when using short pathlength cells</td></tr><tr><td>PS3 peptide synthesizer</td><td>Gyros Protein Technologies</td><td></td><td></td></tr><tr><td>DiscoverSP Microwave Reactor</td><td>CEM</td><td></td><td></td></tr><tr><td>centrifuge</td><td>HERMLE</td><td>Z 206 A</td><td>used a fixed 6x50 mL rotor</td></tr><tr><td>HPLC</td><td>Shimadzu</td><td></td><td>UV Detector</td></tr><tr><td>nuclear magnetic resonance spectrometer</td><td>Avance, Bruker</td><td></td><td>300 MHz</td></tr><tr><td>MALDI-TOF mass spectrometer</td><td>Axima Confidence, Shimadzu</td><td></td><td></td></tr><tr><td>lyophilizer</td><td>Millrock Technology</td><td>BT85A</td><td></td></tr><tr><td>Fourier-Transform Infrared Spectrometer</td><td>Alpha Tensor, Bruker</td><td></td><td></td></tr><tr><td>Transmission Electron Microscope</td><td>Tecnai Spirit, FEI</td><td></td><td>Used with Gatan Orius Fiberoptic CCD digital camera. Accessed at CSCU Center for Nanotechnology</td></tr><tr><td>Circular Dichroism Spectropolarimeter</td><td>J-810, JASCO</td><td></td><td>Used with a six-cell Peltier temperature controller. Accessed at Wesleyan University.</td></tr></tbody></table>

synthesis and characterization of 1,2-dithiolane modified self-assembling peptides

本报告的重点是合成一个 n-终点 12-dithiolane 修饰自组装肽, 并描述了由此产生的自组装超分子结构。合成路线利用固相肽合成与 dithiolane 前体分子的树脂耦合, 3-(acetylthio)-2-(acetylthiomethyl) 丙酸, 和微波辅助硫代乙酸脱的肽从树脂最终裂解前的 N 终点, 产生 12-dithiolane 修饰肽。用高效液相色谱 (HPLC) 纯化 12-dithiolane 肽, 从 Aβ肽与阿尔茨海默病相关的核核中提取, 该肽显示为自组装成交叉β淀粉样纤维。介绍了用傅里叶变换红外光谱 (IR)、环形二色谱光谱 (CD) 和透射电镜 (TEM) 表征淀粉样纤维的协议。采用 12-dithiolane 基团对特征自组装肽进行 n-末端修饰的方法, 现在可以作为模型系统来开发装配后的修改策略, 并探讨动态共价键化学在超分子肽碳纤维表面。

除了最初一步合成的 dithiolane 前体分子, 其余的 12-dithiolane 改良肽合成发生在坚实的支持 (图 1A)。3-溴-2-溴甲基丙酸转化为 3-(acetylthio)-2-(acetylthiomethyl) 丙酸, dithiolane 前驱体, 由1H 和13C 核磁共振 (图 1B和c) 确认, 然后再耦合到自由肽的 n-末端胺仍然在树脂。用氢氧化铵脱硫代乙酸到硫醇, 在 12-dithiolane ?...

Watch this Scientific Journal Video about Synthesis and Characterization of 1,2-Dithiolane Modified Self-Assembling Peptides at JoVE.com

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

一种合成 12-dithiolane 修饰肽的协议, 以及肽自组装产生的超分子结构的表征。

12-Dithiolane 改性自组装肽的合成与表征

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

synthesis-characterization-12-dithiolane-modified-self-assembling

Research

JoVE Journal

Chemistry

7.1K 次观看.  Fairfield University. 一种合成 12-dithiolane 修饰肽的协议, 以及肽自组装产生的超分子结构的表征。

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

Formation of Ordered Biomolecular Structures by the Self-assembly of Short Peptides

In nature, complex functional structures are formed by the self-assembly of biomolecules under mild conditions. Understanding the forces that control self-assembly and mimicking this process in vitro will bring about major advances in the areas of materials science and nanotechnology. Among the available biological building blocks, peptides have several advantages as they present substantial diversity, their synthesis in large scale is straightforward, and they can easily be modified with biological and chemical entities1,2. Several classes of designed peptides such as cyclic peptides, amphiphile peptides and peptide-conjugates self-assemble into ordered structures in solution. Homoaromatic dipeptides, are a class of short self-assembled peptides that contain all the molecular information needed to form ordered structures such as nanotubes, spheres and fibrils3-8. A large variety of these peptides is commercially available.
This paper presents a procedure that leads to the formation of ordered structures by the self-assembly of homoaromatic peptides. The protocol requires only commercial reagents and basic laboratory equipment. In addition, the paper describes some of the methods available for the characterization of peptide-based assemblies. These methods include electron and atomic force microscopy and Fourier-Transform Infrared Spectroscopy (FT-IR). Moreover, the manuscript demonstrates the blending of peptides (coassembly) and the formation of a &#34;beads on a string&#34;-like structure by this process.9 The protocols presented here can be adapted to other classes of peptides or biological building blocks and can potentially lead to the discovery of new peptide-based structures and to better control of their assembly.

This paper describes the formation of highly ordered peptide-based structures by the spontaneous process of self-assembly. The method utilizes commercially available peptides and common lab equipment. This technique can be applied to a large variety of peptides and may lead to the discovery of new peptide-based assemblies.

生物分子有序结构由短肽的自组装形成

In nature, complex functional structures are formed by the self-assembly of biomolecules under mild conditions. Understanding the forces that control ...

科研

化学

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

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

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

分裂和池合成及肽叔酰胺图书馆表征

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

Nucleoside Triphosphates - From Synthesis to Biochemical Characterization

The traditional strategy for the introduction of chemical functionalities is the use of solid-phase synthesis by appending suitably modified phosphoramidite precursors to the nascent chain. However, the conditions used during the synthesis and the restriction to rather short sequences hamper the applicability of this methodology. On the other hand, modified nucleoside triphosphates are activated building blocks that have been employed for the mild introduction of numerous functional groups into nucleic acids, a strategy that paves the way for the use of modified nucleic acids in a wide-ranging palette of practical applications such as functional tagging and generation of ribozymes and DNAzymes. One of the major challenges resides in the intricacy of the methodology leading to the isolation and characterization of these nucleoside analogues.
	
	In this video article, we present a detailed protocol for the synthesis of these modified analogues using phosphorous(III)-based reagents. In addition, the procedure for their biochemical characterization is divulged, with a special emphasis on primer extension reactions and TdT tailing polymerization. This detailed protocol will be of use for the crafting of modified dNTPs and their further use in chemical biology.

The protocol described herein aims to explain and abridge the numerous obstacles in the way of the intricate route leading to modified nucleoside triphosphates. Consequently, this protocol facilitates both the synthesis of these activated building-blocks and their availability for practical applications.

核苷三磷酸 - 从合成到生化特征

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

Synthesis and Characterization of Functionalized Metal-organic Frameworks

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

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

功能化的合成与表征金属 - 有机骨架

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

Constructing Thioether/Vinyl Sulfide-tethered Helical Peptides Via Photo-induced Thiol-ene/yne Hydrothiolation

Here, we describe a detailed protocol for the preparation of thioether-tethered peptides using on-resin intramolecular/intermolecular thiol-ene hydrothiolation. In addition, this protocol describes the preparation of vinyl-sulfide-tethered peptides using in-solution intramolecular thiol-yne hydrothiolation between amino acids that possess alkene/alkyne side chains and cysteine residues at i, i+4 positions. Linear peptides were synthesized using a standard Fmoc-based solid-phase peptide synthesis (SPPS). Thiol-ene hydrothiolation is carried out using either an intramolecular thio-ene reaction or an intermolecular thio-ene reaction, depending on the peptide length. In this research, an intramolecular thio-ene reaction is carried out in the case of shorter peptides using on-resin deprotection of the trityl groups of cysteine residues following the complete synthesis of the linear peptide. The resin is then set to UV irradiation using photoinitiator 4-methoxyacetophenone (MAP) and 2-hydroxy-1-[4-(2-hydroxyethoxy)-phenyl]-2-methyl-1-propanone (MMP). The intermolecular thiol-ene reaction is carried out by dissolving Fmoc-Cys-OH in an N,N-dimethylformamide (DMF) solvent. This is then reacted with the peptide using the alkene-bearing residue on resin. After that, the macrolactamization is carried out using benzotriazole-1-yl-oxytripyrrolidinophosphonium hexafluorophosphate (PyBop), 1-hydroxybenzotriazole (HoBt), and 4-Methylmorpholine (NMM) as activation reagents on the resin. Following the macrolactamization, the peptide synthesis is continued using standard SPPS. In the case of the thio-yne hydrothiolation, the linear peptide is cleaved from the resin, dried, and subsequently dissolved in degassed DMF. This is then irradiated using UV light with photoinitiator 2,2-dimethoxy-2-phenylacetophenone (DMPA). Following the reaction, DMF is evaporated and the crude residue is precipitated and purified using high-performance liquid chromatography (HPLC). These methods could function to simplify the generation of thioether-tethered cyclic peptides due to the use of the thio-ene/yne click chemistry that possesses superior functional group tolerance and good yield. The introduction of thioether bonds into peptides takes advantage of the nucleophilic nature of cysteine residues and is redox-inert relative to disulfide bonds.

We present a protocol for the construction of thioether/vinyl sulfide-tethered helical peptides using photo-induced thiol-ene/thiol-yne hydrothiolation.

利用光致硫醇-烯/yne Hydrothiolation 构造硫醚类/乙烯基硫化物栓系螺旋肽

Here, we describe a detailed protocol for the preparation of thioether-tethered peptides using on-resin intramolecular/intermolecular thiol-ene ...

Synthesis of Information-bearing Peptoids and their Sequence-directed Dynamic Covalent Self-assembly

This protocol presents the use of Lewis acidic multi-role reagents to circumvent kinetic trapping observed during the self-assembly of information-encoded oligomeric strands mediated by paired dynamic covalent interactions in a manner mimicking the thermal cycling commonly employed for the self-assembly of complementary nucleic acid sequences. Primary amine monomers bearing aldehyde and amine pendant moieties are functionalized with orthogonal protecting groups for use as dynamic covalent reactant pairs. Using a modified automated peptide synthesizer, the primary amine monomers are encoded into oligo(peptoid) strands through solid-phase submonomer synthesis. Upon purification by high-performance liquid chromatography (HPLC) and characterization by electrospray ionization mass spectrometry (ESI-MS), sequence-specific oligomers are subjected to high-loading of a Lewis acidic rare-earth metal triflate which both deprotects the aldehyde moieties and affects the reactant pair equilibrium such that strands completely dissociate. Subsequently, a fraction of the Lewis acid is extracted, enabling annealing of complementary sequence-specific strands to form information-encoded molecular ladders characterized by matrix assisted laser desorption/ionization mass spectrometry (MALDI-MS). The simple procedure outlined in this report circumvents kinetic traps commonly experienced in the field of dynamic covalent assembly and serves as a platform for the future design of robust, complex architectures.

A protocol is presented for the synthesis of information-encoded peptoid oligomers and for the sequence-directed self-assembly of these peptoids into molecular ladders using amines and aldehydes as dynamic covalent reactant pairs and Lewis acidic rare-earth metal triflates as multi-role reagents.

信息承载Peptoids及其序列定向动态共价自组装的合成

This protocol presents the use of Lewis acidic multi-role reagents to circumvent kinetic trapping observed during the self-assembly of information-encoded ...

Constructing Cyclic Peptides Using an On-Tether Sulfonium Center

In recent years, cyclic peptides have attracted increasing attention in the field of drug discovery due to their excellent biological activities, and, as a consequence, they are now used clinically. It is, therefore, critical to seek effective strategies for synthesizing cyclic peptides to promote their application in the field of drug discovery. This paper reports a detailed protocol for the efficient synthesis of cyclic peptides using on-resin or intramolecular (intermolecular) bisalkylation. Using this protocol, linear peptides were synthesized by taking advantage of solid-phase peptide synthesis with cysteine (Cys) and methionine (Met) coupled simultaneously on the resin. Further, cyclic peptides were synthesized via bisalkylation between Met and Cys using a tunable tether and an on-tether sulfonium center. The whole synthetic route can be divided into three major processes: the deprotection of Cys on the resin, the coupling of the linker, and the cyclization between Cys and Met in a trifluoroacetic acid (TFA) cleavage solution. Furthermore, inspired by the reactivity of the sulfonium center, a propargyl group was attached to the Met to trigger thiol-yne addition and form a cyclic peptide. After that, the crude peptides were dried and dissolved in acetonitrile, separated, and then purified by high-performance liquid chromatography (HPLC). The molecular weight of the cyclic peptide was confirmed by liquid chromatography-mass spectrometry (LC-MS), and the stability of the cyclic peptide combination with the reductant was further confirmed using HPLC. In addition, the chemical shift in the cyclic peptide was analyzed by 1H nuclear magnetic resonance (1H NMR) spectra. Overall, this protocol aimed to establish an effective strategy for synthesizing cyclic peptides.

This protocol presents the synthesis of cyclic peptides via bisalkylation between cysteine and methionine and the facile thiol-yne reaction triggered by the propargyl sulfonium center.

使用系绳上的锍中心构建环肽

In recent years, cyclic peptides have attracted increasing attention in the field of drug discovery due to their excellent biological activities, and, as ...

<meta charset="utf8"></head><body> 肽水凝胶:ECF-5 的环境响应性凝胶化方法

Preparation of Mechanically Stable Self-Assembled Peptides Hydrogels

Peptide hydrogels are highly hydrophilic, three-dimensional network gels formed by the self-assembly of nanofibers or polymers, creating water-locking networks. Their morphology closely resembles that of the extracellular matrix, allowing them to exhibit both the biological functions of peptides and responsive gelation properties. These unique characteristics have led to their extensive application in tissue engineering, three-dimensional cell culture, cancer therapy, regenerative medicine, and other biomedical fields. This article describes three methods for preparing ECF-5 peptide hydrogels using self-assembling peptides with environmentally responsive gelation processes: (1) pH-responsive gelation: varying pH levels induce the protonation or deprotonation of amino acid residues, altering electrostatic interactions between peptide molecules and promoting their self-assembly into hydrogels; (2) Metal ion addition: polyvalent metal ions chelate with negatively charged amino acid residues, acting as bridges between peptides to form a network hydrogel; (3) Solvent exchange: hydrophobic peptides are initially dissolved in non-polar organic solvents and subsequently induce self-assembly into hydrogels upon transitioning to a polar aqueous environment. These methods utilize conventional experimental procedures to facilitate peptide self-assembly into hydrogels. By designing peptide sequences to align with specific gelation-inducing conditions, it is possible to achieve finely tuned micro/nanostructures and biological functions, highlighting the significant potential of peptide hydrogels in the biomedical domain.

<meta charset="utf8"></head><body>作者聚焦:改进自组装纤维和肽水凝胶的生产以获得卓越的生物相容性

This protocol presents three fast and simple preparation methods that use environmental conditions to trigger the self-assembly of peptides into hydrogels. Additionally, the characterization of peptide hydrogels is described, demonstrating that mechanically stable peptide hydrogels can be formed under these straightforward conditions.

机械稳定的自组装肽水凝胶的制备

Peptide hydrogels are highly hydrophilic, three-dimensional network gels formed by the self-assembly of nanofibers or polymers, creating water-locking ...

12-Dithiolane 改性自组装肽的合成与表征

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此视频中的章节

生物分子有序结构由短肽的自组装形成

分裂和池合成及肽叔酰胺图书馆表征

核苷三磷酸 - 从合成到生化特征

功能化的合成与表征金属 - 有机骨架

利用光致硫醇-烯/yne Hydrothiolation 构造硫醚类/乙烯基硫化物栓系螺旋肽

信息承载Peptoids及其序列定向动态共价自组装的合成

使用系绳上的锍中心构建环肽

机械稳定的自组装肽水凝胶的制备

机械稳定的自组装肽水凝胶的制备

机械稳定的自组装肽水凝胶的制备