Name: direct-coupled electroretinogram (dc-erg) for recording the light-evoked electrical responses of the mouse retinal pigment epithelium
Uploaded: 2020-07-14T12:30:00
Description: Watch this Scientific Journal Video about Direct-Coupled Electroretinogram DC-ERG for Recording the Light-Evoked Electrical Responses of the Mouse Retinal Pigment Epithelium at JoVE.com

这项工作得到了国家内部国家基金的支持。作者衷心感谢谢尔顿·米勒博士在RPE生理学和疾病方面的科学指导、技术建议和专业知识。作者感谢梅根·科佩拉和动物护理人员管理老鼠群落，感谢塔伦·班萨尔博士、周雷蒙德博士和王元博士的技术支持。

该协议遵循国家眼科研究所动物护理和使用委员会批准的动物研究协议中概述的动物护理指南。
1. 为DC-ERG导入光刺激协议
注：按照以下说明将 DC-ERG 的光刺激协议导入 ERG 系统软件（材料表）。该协议包括 0.5 分钟的预刺激间隔，然后是 7 分钟的光步（10 cd/m2），最后为 1.5 分钟的刺激后间隔。选择光强为10 cd/m2（1日志10...

<ol>
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S., 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=Light-evoked+responses+of+the+retinal+pigment+epithelium:+changes+accompanying+photoreceptor+loss+in+the+mouse.">Light-evoked responses of the retinal pigment epithelium: changes accompanying photoreceptor loss in the mouse.</a> Journal of Neurophysiology. 104 (1), 391-402 (2010).</li><li>Wu, J., Marmorstein, A. D., Peachey, N. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Functional+abnormalities+in+the+retinal+pigment+epithelium+of+CFTR+mutant+mice.">Functional abnormalities in the retinal pigment epithelium of CFTR mutant mice.</a> Experimental Eye Research. 83 (2), 424-428 (2006).</li><li>Wu, J., Peachey, N. S., Marmorstein, A. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Light-evoked+responses+of+the+mouse+retinal+pigment+epithelium.">Light-evoked responses of the mouse retinal pigment epithelium.</a> Journal of Neurophysiology. 91 (3), 1134-1142 (2004).</li><li>Peachey, N. S., Stanton, J. B., Marmorstein, A. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Noninvasive+recording+and+response+characteristics+of+the+rat+dc-electroretinogram.">Noninvasive recording and response characteristics of the rat dc-electroretinogram.</a> Visual Neuroscience. 19 (6), 693-701 (2002).</li><li>Samuels, I. S., Bell, B. A., Pereira, A., Saxon, J., Peachey, N. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Early+retinal+pigment+epithelium+dysfunction+is+concomitant+with+hyperglycemia+in+mouse+models+of+type+1+and+type+2+diabetes.">Early retinal pigment epithelium dysfunction is concomitant with hyperglycemia in mouse models of type 1 and type 2 diabetes.</a> Journal of Neurophysiology. 113 (4), 1085-1099 (2015).</li><li>Marmorstein, L. Y., 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=The+light+peak+of+the+electroretinogram+is+dependent+on+voltage-gated+calcium+channels+and+antagonized+by+bestrophin+(best-1).">The light peak of the electroretinogram is dependent on voltage-gated calcium channels and antagonized by bestrophin (best-1).</a> Journal of General Physiology. 127 (5), 577-589 (2006).</li><li>Zhang, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Invest.+Ophtalmol.+Vis.+Sci.">Invest. Ophtalmol. Vis. 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G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Age-+and+gene-dosage-dependent+cre-induced+abnormalities+in+the+retinal+pigment+epithelium.">Age- and gene-dosage-dependent cre-induced abnormalities in the retinal pigment epithelium.</a> American Journal of Pathology. 184 (6), 1660-1667 (2014).</li><li>Gallemore, R. P., Steinberg, R. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Light-evoked+modulation+of+basolateral+membrane+Cl-+conductance+in+chick+retinal+pigment+epithelium:+the+light+peak+and+fast+oscillation.">Light-evoked modulation of basolateral membrane Cl- conductance in chick retinal pigment epithelium: the light peak and fast oscillation.</a> Journal of Neurophysiology. 70 (4), 1669-1680 (1993).</li><li>Blaug, S., Quinn, R., Quong, J., Jalickee, S., Miller, S. 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关键步骤
良好的 DC-ERG 记录需要稳定的电极，这些电极没有气泡，这些气泡会产生伪影和不需要的漂移，因为它们对排气和温度变化非常敏感。当电极放置在 HBSS 沐浴溶液中，然后继续进行鼠标记录时，必须实现稳定的基线。小气泡往往聚集在毛细管电极底部或硅胶垫片周围，一旦电极支架完全组装完毕，就很难看到。当存在几个气泡时，轻轻轻拂支架将释放它?...

视网膜色素上皮（RPE）是一个专用细胞的单层，它与眼睛的后段一起，发挥关键功能，维持视网膜平衡1。RPE支持光感受器，在称为视觉周期2的过程中再生光子捕获视觉色素，参与棚外段尖3的日生噬菌体，以及在光感受器和胆囊4、5之间运输营养物质和代谢产物。RPE功能异常是众多人类视网膜疾病的根据，如年龄相关的黄斑变性6，勒伯的先天性阿龙病7，8和最佳维泰利形成黄斑营养不良9。由于供体眼组织往往很难仅仅用于研究目的，动物模型与基因修饰可以提供另一种方式来研究视网膜疾病的发展10，11。此外，CRISPR cas9技术的出现和应用现在允许在一个简单的、单步的进程中引入基因组（敲击）或删除（敲出），超过先前基因靶向技术12的局限性。新鼠标型号13 的可用性激增，需要更高效的记录协议来非侵入式评估 RPE 功能。
使用直接耦合电雷电图 （DC-ERG） 技术可以测量 RPE 的光唤起电响应。当与测量光感受器（A 波）和双极（b 波）细胞反应14的传统ERG记录结合使用时，DC-ERG可以定义RPE的响应特性如何随着视网膜退化15、16、17的变化而变化，或者RPE功能障碍是否先于光受体损失。该协议描述了一种改编自马莫尔斯坦、佩奇和同事的工作方法，他们首先开发了DC-ERG技术16、18、19、20，并改进了可重复性和易用性。
DC-ERG 记录难以执行，因为采集时间长（9 分钟），在此期间，任何干扰或噪声引入都可能使数据解释复杂化。这种新方法的优点是基线在更短的时间内达到稳定状态，从而减少了动物过早从麻醉中醒来的可能性，并且不容易在毛细管电极中形成气泡。

<table>
	<tbody>
		<tr>
			<td>Ag/AgCl (mouth) Electrode</td>
			<td>WPI Inc</td>
			<td>EP1</td>
			<td>Mouth reference electrode for mouse</td>
		</tr>
		<tr>
			<td>Ceramic Tile</td>
			<td>Sutter Instrument</td>
			<td>CTS</td>
			<td>Used to cut the glass capillary tube to an appropriate size</td>
		</tr>
		<tr>
			<td>Cotton Tipped Cleaning Stick</td>
			<td>Puritan Medical Products</td>
			<td>867-WC No Glue</td>
			<td>To be used as a spacer to improve the fit of the electrode holder assembly</td>
		</tr>
		<tr>
			<td>Electroretinogram (ERG) System</td>
			<td>Diagnosys LLC</td>
			<td>E3 System</td>
			<td>Visual electrophysiology system to diagnose ophthalmic conditions in vision research and drug trials</td>
		</tr>
		<tr>
			<td>Bunsen Burner</td>
			<td>Argos Technologies</td>
			<td>BW20002460</td>
			<td>Or equivlaent to shape glass under flame</td>
		</tr>
		<tr>
			<td>Glass Capillary Tube (1.5 mm)</td>
			<td>Sutter Instruments</td>
			<td>BF150-75</td>
			<td>For filling with HBSS and making contact to the cornea</td>
		</tr>
		<tr>
			<td>Hank&#8217;s Buffered Salt Solution (HBSS)</td>
			<td>Thermo Fisher Scientific Inc</td>
			<td>14175-095</td>
			<td>Commercially available. Maintain at RT</td>
		</tr>
		<tr>
			<td>In-Line Filter</td>
			<td>Whatman</td>
			<td>6722-5001</td>
			<td>To protect vacuum pump from aerosols</td>
		</tr>
		<tr>
			<td>Low Noise Cable for Microelectrode Holders</td>
			<td>WPI Inc</td>
			<td>5372</td>
			<td>Suggested for improving the length and placement of the cables and electrode holder assemblies</td>
		</tr>
		<tr>
			<td>Magnetic Ball Joint</td>
			<td>WPI Inc</td>
			<td>500871</td>
			<td>For magnetically positioning the electrode holder assembly on the stage</td>
		</tr>
		<tr>
			<td>MatLab</td>
			<td>Mathworks</td>
			<td></td>
			<td>MatLab: For editing the analysis software</td>
		</tr>
		<tr>
			<td>Matlab Curvefit Toolbox</td>
			<td>Mathworks</td>
			<td></td>
			<td>Toolbox for MatLab (only required for editing the analysis software)</td>
		</tr>
		<tr>
			<td>MatLab Compiler</td>
			<td>Mathworks</td>
			<td></td>
			<td>Toolbox for MatLab (only required for editing and re-releasing the analysis software)</td>
		</tr>
		<tr>
			<td>MatLab Runtime version 9.5</td>
			<td>Mathworks</td>
			<td>R2018b (9.5)</td>
			<td>Required to run the analysis software: https://www.mathworks.com/products/compiler/matlab-runtime.html</td>
		</tr>
		<tr>
			<td>Microelectrode Holders (45 degrees)</td>
			<td>WPI Inc</td>
			<td>MEH345-15</td>
			<td>For holding the capillaries</td>
		</tr>
		<tr>
			<td>Needle (25 ga)</td>
			<td>Covidien</td>
			<td>8881250313</td>
			<td>For filling the capillary tubes with HBSS</td>
		</tr>
		<tr>
			<td>needle (ground) electrode</td>
			<td>Rhythmlink</td>
			<td>13mm - one elctrode</td>
			<td>Subdermal needle electrode (ground) for mouse (13mm long, 0.4mm diameter needle, 1.5m leadwire)</td>
		</tr>
		<tr>
			<td>Regulator/Power Conditioner</td>
			<td>Furman</td>
			<td>P-1800</td>
			<td>Or equivalent to remove DC-offset from noise introduced through power line</td>
		</tr>
		<tr>
			<td>Syringe (12 mL)</td>
			<td>Monoject</td>
			<td>1181200777</td>
			<td>For filling the capillary tubes with HBSS</td>
		</tr>
		<tr>
			<td>T-clip</td>
			<td>Cole-Parmer</td>
			<td>06852-20</td>
			<td>For electrode holder assembly</td>
		</tr>
		<tr>
			<td>Vacuum Desiccator</td>
			<td>Bel-Art</td>
			<td>420120000</td>
			<td>Clear polycarbonate bottom &#38; cover</td>
		</tr>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Pharmacological treatment</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Lubricant eye gel</td>
			<td>Alcon</td>
			<td>0078-0429-47</td>
			<td>Helps lubricates corneal surface and maintain electrical contact with capillary electrodes</td>
		</tr>
		<tr>
			<td>Phenylephrine Hydrochloride 2.5%</td>
			<td>Akorn</td>
			<td>17478-201-15</td>
			<td>Short acting mydriatic eye drops (for pupil dilation)</td>
		</tr>
		<tr>
			<td>Proparacaine Hydrochloride 0.5%</td>
			<td>Akorn</td>
			<td>17478-263-12</td>
			<td>Local anesthetic for ophthalmic instillation</td>
		</tr>
		<tr>
			<td>Tropicamide 0.5%</td>
			<td>Akorn</td>
			<td>17478-101-12</td>
			<td>Short acting mydriatic eye drops (for pupil dilation)</td>
		</tr>
		<tr>
			<td>Xylazine</td>
			<td>AnaSed</td>
			<td>sc-362949Rx</td>
			<td>Analgesic and muscle relaxant</td>
		</tr>
		<tr>
			<td>Zetamine (Ketamine HCl)</td>
			<td>VetOne</td>
			<td>501072</td>
			<td>Anesthetic for intramuscular injections</td>
		</tr>
	</tbody>
</table>

direct-coupled electroretinogram (dc-erg) for recording the light-evoked electrical responses of the mouse retinal pigment epithelium

视网膜色素上皮 （RPE） 是位于视网膜和胆光分离之间的特殊单层细胞，可保持光受体的整体健康和结构完整性。RPE 是极化的，表现在基础和基础位置的受体或通道，并执行水、离子、代谢物和分泌多个细胞因子的矢量传输。
可以使用直接耦合ERG（DC-ERG）对RPE函数进行体内非侵入性测量。DC-ERG 背后的方法由 Marmorstein、Peachey 和同事率先使用定制的刺激记录系统，后来演示了使用市售系统。DC-ERG 技术使用充满 Hank 缓冲盐溶液 （HBSS） 的玻璃毛细管来测量由于光受体活动而导致的光线激发浓度变化导致的 RPE 的较慢电响应。DC-ERG 记录的长期光线刺激和长度使其易受漂移和噪音的影响，导致可用录像的收率低。在这里，我们提出了一种快速、可靠的方法，通过利用真空压力减少/消除 HBSS 和电极支架的加气产生的气泡，从而提高录像的稳定性，同时降低噪音。此外，使用压量器/电源调节器衰减电源线伪影。我们包括商用ERG系统的必要光刺激协议，以及用于分析DC-ERG组件的脚本：c波、快速振荡、光峰值和非响应。由于改进了易录音和快速分析工作流程，这种简化的协议在测量RPE功能、疾病进展和药理干预评估中与年龄相关的变化特别有用。

图 2是 miR-204 ko/ko cre/= （条件 KO） 和野生类型 （WT） 小鼠的样本数据集。MiR-204 ko/ko cre/+ 是视网膜色素上皮中具有微RNA 204有条件淘汰的小鼠。这些小鼠是由交叉絮克miR-204小鼠（由NEIGEF生产）22与VMD2-CRE小鼠23生成。MiR-204在RPE中高度表达，它调节对保持紧密结完整（例如，结接完整性）、通过Kir 7.1钾通道的表达维持钾平衡以及几个视觉循环...

Watch this Scientific Journal Video about Direct-Coupled Electroretinogram DC-ERG for Recording the Light-Evoked Electrical Responses of the Mouse Retinal Pigment Epithelium at JoVE.com

Direct-Coupled Electroretinogram DC-ERG for Recording the Light-Evoked Electrical Responses of the Mouse Retinal Pigment Epithelium

在这里，我们提出了一种方法，使用马莫斯坦、佩奇和同事在21世纪早期首次描述的一种称为DC-ERG的技术，记录小鼠视网膜色素上皮（RPE）的光唤起电反应。

直接耦合电雷电图（DC-ERG），用于记录小鼠视网膜颜料皮皮的光唤起电响应

The retinal pigment epithelium (RPE) is a specialized monolayer of cells strategically located between the retina and the choriocapillaris that maintain ...

DC-ERG技术可用于视网膜色素上皮功能的非回避评估，以监测与年龄相关的变化或疾病进展，并评估药理干预作用。该技术通过简化毛细管电极制备，提高了DC-ERG的再现能力和易用性。它还可以补充一个标准的欧姆软件应用程序，以方便分析。首先，小心地将 25 规格的注射器针头通过硅橡胶垫片滑到电极支架的后壁上。用脱气的HSS填充电极支架的底座，同时慢慢缩回针头，注意不要冒泡，在不拧紧的情况下更换螺纹盖。重新插入注射器针头，用 HBSS 填充间隙内的空间，并在填充时水平握住毛细管，以防止溶液从另一端逸出。抓住弯曲端的填充毛细管，通过松开的盖缓慢插入另一端，并将螺钉盖拧紧到位。倾斜电极支架，使毛细管电极朝上，让任何气泡流出，并在真空室中解气 5 到 10 分钟。然后，慢慢释放真空并重新填充电极支架和玻璃毛细管，如所证明的。要为微型电子支架制作一个定制支架，请从数字 8 T 形夹的一侧拆下黑色聚乙酰剪辑，并使用带磁球接头的气缸底座进行加工以调整高度。将经过修改的 T 形夹子固定到带 M3 尺寸螺母的磁性球安装螺钉上，并在大约一英寸锥形木手柄中滑动，从棉尖清洁棒修改，以一定角度将微型电子支架固定到定制的 T 形夹磁性球接头支架中。然后，使用稀土磁铁缸底座将定制的电极支架牢固地固定在舞台的金属板上，从而在 180 度轴上实现 360 度旋转。要执行电极测试，首先，将完全组装的 HBSS 填充毛细管微电极轻轻降低为 HBSS 的小容器中。将针接地电极和银、氯化银中心颗粒参考电极放在同一 HBSS 中，以完成电路并选择或创建适当的标识符来描述要测试的鼠标。要选择要执行的直接耦合电retinogram协议，请单击协议并选择DC-ERG。单击"运行"。将弹出一个对话框，显示患者信息。如果信息正确，请单击"是"，然后继续执行六个步骤之一。关闭法拉第笼的门，然后单击阻抗以显示阻抗模式。验证嘴参考、尾接地和记录电极的值是否可接受，然后单击步长以继续执行步骤，以执行第 6 步中的 4 步以测试基线稳定性。要开始查看跟踪，请单击预览。跟踪应为低噪声，峰值振幅小于 200 微伏。要放置小鼠和电极进行实验，对静种小鼠的角膜进行麻醉，在将角膜扩张至2.5%苯丙胺HCL和5%热带酰胺之前，先对角膜进行麻醉。在 ERG 系统软件中，验证是否选择了正确的患者。单击协议。在协议说明下，选择 DC-ERG 并单击"运行"。单击"是"以验证是否执行了正确的测试。使用六步中的第一步打开圆顶内昏暗的红灯，然后将鼠标放在加热的录音桌上。使用钳子小心地帐篷后腿的皮肤。用一只手牢牢握住针电极，用另一只手将电极皮下插入后腿，将电极固定到位。将参考银、氯化银电极放入动物的嘴里，使中心颗粒沿着后脸颊放置，并固定在牙齿后面。在将毛细管电极放在眼睛上之前，将电极支架与玻璃毛细管垂直方向放置，然后用食指轻拂电极支架，以去除可能引入的任何气泡。使用 25 量针用 HBSS 填充毛细管尖端，并检查毛细管，以确保尖端中没有气泡。放置电极支架，使充满 HBSS 填充毛细血管的打开尖端与角膜温和接触。并注意避免引入气泡，倒置润滑剂眼凝胶分配器丢弃初始滴。然后，将一滴润滑剂眼凝胶放在每只眼睛上，以保持导电性并防止在录制过程中干燥。要记录 DC-ERG，请单击步骤以选择六个步骤中的第五步，然后单击阻抗以使用阻抗检查屏幕检查左右眼的电阻。每只眼睛的记录电极的阻抗值应相似。接地和参考电极的阻抗值应小于 10 千赫。单击预览以查看左右眼睛的轨迹，并等待长达 10 分钟才能实现稳定的基线。然后，单击"停止"退出跟踪预览，然后单击"运行"以开始录制。此处显示了来自条件挖空和野生类型鼠标的示例数据集。在此分析中，微量受到电极中微小气泡的损害。它增加了跟踪中的峰到峰噪声。在另外一项分析中，在将微电极在电极支架内组装之前，使用真空室消除了气泡。可以计算初始 25 秒的最佳拟合线，从而可以重新分配漂移校正响应，并识别 DC-ERG 元件的振幅。如预期的那样，RPE中固化7.1钾通道的表达减少大大衰减c波和快速振荡，表明视网膜色素上皮电性能有显著损伤。在这里，显示直流-ERG分量的相对振幅，这些分量被规范化为野生型，并针对相对两个最大的光唤起的波幅绘制。这种形式的分析可以确定，光感受器活动本身的减少是否可解释RPE的电响应降低。或者，如果存在源自 RPE 的潜在缺陷。请记住，在移动到鼠标记录之前，要获得稳定的基线，并定期重新检查电极，以发现可能引入的气泡。在 DC-ERG 之前可以记录深色适应 ERG，以测量锥形驱动的视网膜功能。在DC-ERG之后，还可以进行光适应ERG，以评估锥形驱动的视网膜反应。

Research

JoVE Journal

Chemistry

Direct-Coupled Electroretinogram (DC-ERG) for Recording the Light-Evoked Electrical Responses of the Mouse Retinal Pigment Epithelium

LabVIEW-operated Novel Nanoliter Osmometer for Ice Binding Protein Investigations

LabVIEW操作的新型纳升渗透压仪冰结合蛋白的调查

Ice-binding proteins (IBPs), including antifreeze proteins, ice structuring proteins, thermal hysteresis proteins, and ice recrystallization inhibition ...

科研

化学

Production of Disulfide-stabilized Transmembrane Peptide Complexes for Structural Studies

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 ...

Structure and Coordination Determination of Peptide-metal Complexes Using 1D and 2D 1H NMR

Structure and Coordination Determination of Peptide-metal Complexes Using 1D and 2D 1H NMR

Copper (I) binding by metallochaperone transport proteins prevents copper oxidation and release of the toxic ions that may participate in harmful redox ...

A High-throughput-compatible FRET-based Platform for Identification and Characterization of Botulinum Neurotoxin Light Chain Modulators

Botulinum neurotoxin (BoNT) is a potent and potentially lethal bacterial toxin that binds to host motor neurons, is internalized into the cell, and ...

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

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 ...

Optimization of Synthetic Proteins: Identification of Interpositional Dependencies Indicating Structurally and/or Functionally Linked Residues

优化合成蛋白质：Interpositional依赖性的鉴定指示在结构和/或功能性连接的残留

Protein alignments are commonly used to evaluate the similarity of protein residues, and the derived consensus sequence used for identifying functional ...

Synthesis of Protein Bioconjugates via Cysteine-maleimide Chemistry

Synthesis of Protein Bioconjugates via Cysteine-maleimide Chemistry

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

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

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

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 ...

Using Capillary Electrophoresis to Quantify Organic Acids from Plant Tissue: A Test Case Examining Coffea arabica Seeds

Using Capillary Electrophoresis to Quantify Organic Acids from Plant Tissue: A Test Case Examining Coffea arabica Seeds

利用毛细管电泳从植物组织量化有机酸：一个测试用例检查<em&gt;小粒种咖啡</em&gt;种子

Carboxylic acids are organic acids containing one or more terminal carboxyl (COOH) functional groups. Short chain carboxylic acids (SCCAs; carboxylic ...

Insights into the Interactions of Amino Acids and Peptides with Inorganic Materials Using Single-Molecule Force Spectroscopy

洞察氨基酸和多肽与无机材料的使用相互作用的单分子力谱

The interactions between proteins or peptides and inorganic materials lead to several interesting processes. For example, combining proteins with minerals ...