Name: construction of a wireless-enabled endoscopically implantable sensor for ph monitoring with zero-bias schottky diode-based receiver
Uploaded: 2021-08-27T13:30:00
Description: Watch this Scientific Journal Video about Construction of a Wireless-Enabled Endoscopically Implantable Sensor for pH Monitoring with Zero-Bias Schottky Diode-based Receiver at JoVE.com

作者感激地感谢查理大学（项目GA UK No 176119）支持这项研究。这项工作得到了查理大学研究项目PROGRES Q 28（肿瘤学）的支持。

本研究没有涉及任何活体动物。该实验是在由猪食道和胃组成的 离体 模型上进行的。胃和食道是从当地屠宰场购买的，作为他们的标准产品。此程序符合捷克法律，由于"3R"原则（替换，减少和改进），我们更喜欢它。
1. pH电极组件的制造
注：在 pH 传感器组件的整个制造过程中，请遵守处理静电放电 （ESD） 敏感组件的注意事项。使用烙铁时要小心...

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(139), e57268 (2018).</li><li>Pavelka, M., Roth, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Parietal+Cells+Of+Stomach:+Secretion+Of+Acid.">Parietal Cells Of Stomach: Secretion Of Acid.</a> Functional Ultrastructure. , 202-203 (2010).</li><li>Jones, R. D., Neuman, M. R., Sanders, G., Cross, F. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Miniature+antimony+pH+electrodes+for+measuring+gastroesophageal+reflux.">Miniature antimony pH electrodes for measuring gastroesophageal reflux.</a> The Annals of Thoracic Surgery. 33 (5), 491-495 (1982).</li><li>Waugh, R. W., Buted, R. 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这种方法适用于致力于开发新型有源可植入医疗器械的研究人员。它需要熟练程度地制造带有表面贴装元件的电子原型。该协议中的关键步骤与电子产品的制造有关，特别是填充PCB，这很容易导致操作员在放置和焊接小组件时出错。然后，正确的封装对于延长暴露在潮湿和液体中的设备的使用寿命至关重要。植入方法的设计考虑了简单性。植入过程中食道穿孔或其他不良事件的风险很小。止血夹?...

蒙特利尔共识将胃食管反流病（GERD）定义为"当胃内容物反流引起不愉快的症状和/或并发症时发展的病症"。它可能与其他特定并发症相关，例如食管狭窄、Barrett 食管或食管腺癌。胃食管反流病影响约20%的成年人口，主要发生在经济地位高的国家1。
病理性反流的动态pH值监测（酸暴露时间超过6%）使我们能够区分症状与酸性或非酸性胃食管反流之间的关系2，3。对于对 PPI（质子泵抑制剂）治疗无反应的患者，pH 监测可以回答是否为病理性胃食管反流，以及为什么患者对标准 PPI 治疗无反应。目前提供各种pH和阻抗监测选项。其中一种较新的可能性是使用植入式设备进行无线监控4，5。
胃食管反流病与食管下括约肌 （LES） 疾病相关，食管压测量期间显示的收缩不是病理性的，但在长期胃食管反流病中振幅减小。LES由平滑肌组成，由于肌源性和神经源性因素而维持强直收缩。由于迷走神经介导的抑制作用，一氧化氮作为神经递质6，它会松弛下来。
在犬回流模型中，用两对电极进行电刺激可以增加LES的收缩时间7。LES的松弛（包括吞咽期间的残余压力）不受低频和高频刺激的影响。高频刺激是显而易见的选择，因为它需要更少的功率并延长电池寿命。
虽然食管下括约肌的电刺激治疗（ET）在GERD患者的治疗中是一个相对较新的概念，但这种疗法被证明是安全有效的。这种形式的治疗已被证明可以显着和持久地缓解GERD的症状，同时消除PPI治疗的需要并减少食管酸暴露8，9，10。
目前用于诊断胃食管反流病的最先进的pH传感器是Bravo设备11，12。在估计体积为1.7 cm3时，它可以直接植入食道，有或没有视觉内窥镜反馈，并提供食道pH值的24小时以上监测。
考虑到电刺激疗法是治疗对标准疗法无反应的胃食管反流病的最有希望的替代方案之一8，13，因此将pH传感器的数据提供给神经刺激器是有意义的。最近的研究显示了该领域未来发展的明确道路，这将导致刚性一体化植入式装置，该装置将驻留在神经刺激部位14，15。为此，ISFET（离子敏感场效应晶体管）是最好的传感器类型之一，因为它具有微型性质，可以在片上集成参考电极（在这种情况下是金），并且灵敏度足够高。在硅上，ISFET类似于标准MOSFET（金属氧化物半导体场效应晶体管）的结构。然而，通常连接到电气端子的栅极被与周围环境直接接触的一层活性物质所取代。对于pH敏感的ISFET，该层由氮化硅（Si3N4）16形成。
内窥镜植入式设备的主要缺点是电池尺寸的固有限制，这可能导致这些设备的使用寿命缩短，或促使制造商开发先进的算法，以更低的能源成本提供所需的效果。这种算法的一个例子是用于GERD按需神经刺激治疗的闭环系统。与连续血糖仪（CGM）+胰岛素泵系统17类似，这样的系统将采用食管pH传感器或其他传感器来检测食管下括约肌的当前压力以及神经刺激装置。
对神经刺激治疗的反应和对神经刺激模式的要求可以是个体的13。因此，重要的是要开发独立的传感器，这些传感器可用于功能障碍的诊断和表征，或根据患者的个体要求积极参与校准神经刺激系统18。这些传感器应尽可能小，以免影响器官的正常功能。
本手稿介绍了一种设计和制造基于 ISFET 的 pH 传感器的方法，该传感器具有幅度偏移键控 （ASK） 发射器和基于小尺寸无源直馏器的接收器。基于该解决方案的简单架构，pH数据可以通过外部接收器甚至可植入式神经刺激器接收，而不会产生任何显着的体积或功率损失。选择ASK调制是因为无源接收器的性质，它只能检测接收的RF信号功率（通常称为"接收信号强度"）。作为补充材料嵌入的原理图显示了设备的结构。它直接由两节AG1碱性电池供电，这两节电池提供2.0-3.0 V之间的电压（基于充电状态）。电池为内部微控制器供电，该微控制器利用其ADC（模数转换器）、DAC（数模转换器）、内部运算放大器和FVR（固定电压基准）外设来偏置ISFET pH传感器。由此产生的"栅极"电压（金参比电极）与周围环境的pH值成正比。稳定的IDS 电流由低端R2检测电阻提供。ISFET传感器的电源连接到运算放大器的同相输入，而反相输入连接到DAC模块设置为960 mV的输出电压。运算放大器的输出连接到ISFET的漏极引脚。该运算放大器调节漏极电压，使R2电阻上的电压差始终为960 mV。因此，29 μA的恒定偏置电流流过ISFET（正常工作时）。然后用ADC测量栅极电压。然后，微控制器通过其中一个GPIO（通用输入/输出）引脚为RF发射器供电并传输序列。RF发射器电路涉及晶体和匹配网络，该网络将输出匹配到50 Ω阻抗。
对于这里演示的实验，我们使用猪胃，其中一长段食道安装在标准化的塑料模型中。这是练习内窥镜技术的常用模型，例如ESD（内窥镜粘膜下剥离），POEM（口腔内窥镜肌切开术），内窥镜粘膜切除术（EMR），止血等。关于最接近人体器官的解剖参数，我们使用体重40-50公斤的猪的胃和食道。

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>AG1 battery</td>
			<td>Panasonic</td>
			<td>SR621SW</td>
			<td>Two batteries per one implant</td>
		</tr>
		<tr>
			<td>Battery holder</td>
			<td>MYOUNG</td>
			<td>MY-521-01</td>
			<td></td>
		</tr>
		<tr>
			<td>Copper enamel wire for the antenna</td>
			<td>pro-POWER</td>
			<td>QSE Wire - 0.15 mm diameter, 38 SWG</td>
			<td></td>
		</tr>
		<tr>
			<td>Epoxy for encapsulation</td>
			<td>Loctite</td>
			<td>EA M-31 CL</td>
			<td>Two-part medical-grade ISO10993 compliant epoxy</td>
		</tr>
		<tr>
			<td>FEP cable for pH sensor</td>
			<td>Molex / Temp-Flex</td>
			<td>100057-0273</td>
			<td></td>
		</tr>
		<tr>
			<td>Flux cleaner</td>
			<td>Shesto</td>
			<td>UTFLLU05</td>
			<td>Prepare 5% solution in deionized water for cleaning by sonication</td>
		</tr>
		<tr>
			<td>Hemostatic clip</td>
			<td>Boston Scientific</td>
			<td>Resolution</td>
			<td></td>
		</tr>
		<tr>
			<td>Hot air gun + soldering iron</td>
			<td>W.E.P.</td>
			<td>Model 706</td>
			<td>Any soldering iron capable of soldering with tin and hot-air gun capable of maintaining 260 &#176;C can be used</td>
		</tr>
		<tr>
			<td>Impedance matching software</td>
			<td>Iowa Hills Software</td>
			<td>Smith Chart</td>
			<td>Can be downloaded from http://www.iowahills.com/9SmithChartPage.html - alternatively, any RF design software supports calculation of impedance matching components</td>
		</tr>
		<tr>
			<td>ISFET pH sensor on a PCB</td>
			<td>WinSense</td>
			<td>WIPS</td>
			<td>Order a model pre-mounted on a PCB with on-chip gold reference electrode</td>
		</tr>
		<tr>
			<td>Laboratory pH meter</td>
			<td>Hanna Instruments</td>
			<td>HI2210-02</td>
			<td>Used with HI1131B glass probe</td>
		</tr>
		<tr>
			<td>Microcontorller programmer</td>
			<td>Microchip</td>
			<td>PICkit 3</td>
			<td>Other PIC16 compatible programmers can be also used</td>
		</tr>
		<tr>
			<td>Pig stomach with esophagus</td>
			<td>Local pig farm</td>
			<td>Obtained from approx. 40&#8211;50 kg pig</td>
			<td>It is important that the stomach includes a full length of the esophagus.</td>
		</tr>
		<tr>
			<td>Printed circuit board - receiver</td>
			<td>Choose preferred PCB supplier</td>
			<td>According to pcb2.zip data</td>
			<td>One layer, 0.8 mm thickness, FR4, no mask</td>
		</tr>
		<tr>
			<td>Printed circuit board - sensor</td>
			<td>Choose preferred PCB supplier</td>
			<td>According to pcb1.zip data</td>
			<td>Two-layer with PTH, 0.6 mm thickness, FR4, 2x mask</td>
		</tr>
		<tr>
			<td>Receiver - 0R</td>
			<td>Vishay</td>
			<td>CRCW04020000Z0EDC</td>
			<td>See Figure 12 and Figure 13 for placement</td>
		</tr>
		<tr>
			<td>Receiver - 1.5 pF</td>
			<td>Murata</td>
			<td>GRM0225C1C1R5CA03L</td>
			<td>See Figure 12 and Figure 13 for placement</td>
		</tr>
		<tr>
			<td>Receiver - 100 pF</td>
			<td>Murata</td>
			<td>GRM0225C1E101JA02L</td>
			<td>See Figure 12 and Figure 13 for placement</td>
		</tr>
		<tr>
			<td>Receiver - 33 nH</td>
			<td>Pulse Electronics</td>
			<td>PE-0402CL330JTT</td>
			<td>See Figure 12 and Figure13 for placement</td>
		</tr>
		<tr>
			<td>Receiver - RF schottky diodes</td>
			<td>MACOM</td>
			<td>MA4E2200B1-287T</td>
			<td>See Figure 12 and Figure 13 for placement</td>
		</tr>
		<tr>
			<td>Receiver - SMA antenna</td>
			<td>LPRS</td>
			<td>ANT-433MS</td>
			<td></td>
		</tr>
		<tr>
			<td>Receiver - SMA connector</td>
			<td>Linx Technologies</td>
			<td>CONSMA001</td>
			<td>See Figure 12 and Figure 13 for placement</td>
		</tr>
		<tr>
			<td>Sensor - C1</td>
			<td>Murata</td>
			<td>GRM0225C1H8R0DA03L</td>
			<td>8 pF 0402 capacitor</td>
		</tr>
		<tr>
			<td>Sensor - C2</td>
			<td>Murata</td>
			<td>GRM0225C1H8R0DA03L</td>
			<td>8 pF 0402 capacitor</td>
		</tr>
		<tr>
			<td>Sensor - C3</td>
			<td>Murata</td>
			<td>GCM155R71H102KA37D</td>
			<td>1 nF 0402 capacitor</td>
		</tr>
		<tr>
			<td>Sensor - C4</td>
			<td>Murata</td>
			<td>GRM0225C1H1R8BA03L</td>
			<td>1.8 pF</td>
		</tr>
		<tr>
			<td>Sensor - C5</td>
			<td>Vishay</td>
			<td>CRCW04020000Z0EDC</td>
			<td>Place 0R 0402 resistor or use to match the antenna</td>
		</tr>
		<tr>
			<td>Sensor - C6</td>
			<td>Murata</td>
			<td>GRM155C81C105KE11J</td>
			<td>1 uF 0402 capacitor</td>
		</tr>
		<tr>
			<td>Sensor - C7</td>
			<td>Murata</td>
			<td>GRM155C81C105KE11J</td>
			<td>1 uF 0402 capacitor</td>
		</tr>
		<tr>
			<td>Sensor - C8</td>
			<td>Murata</td>
			<td>GRM022R61A104ME01L</td>
			<td>100 nF 0402 capacitor</td>
		</tr>
		<tr>
			<td>Sensor - IC1</td>
			<td>Microchip</td>
			<td>MICRF113YM6-TR</td>
			<td>MICRF113 RF transmitter</td>
		</tr>
		<tr>
			<td>Sensor - IC2</td>
			<td>Microchip</td>
			<td>PIC16LF1704-I/ML</td>
			<td>PIC16LF1704 low-power microcontroller</td>
		</tr>
		<tr>
			<td>Sensor - R1</td>
			<td>Vishay</td>
			<td>CRCW040210K0FKEDC</td>
			<td>10 kOhm 0402 resistor</td>
		</tr>
		<tr>
			<td>Sensor - R2</td>
			<td>Vishay</td>
			<td>CRCW040233K0FKEDC</td>
			<td>33 kOhm 0402 resistor</td>
		</tr>
		<tr>
			<td>Sensor - R3</td>
			<td>Vishay</td>
			<td>CRCW04021K00FKEDC</td>
			<td>1 kOhm 0402 resistor</td>
		</tr>
		<tr>
			<td>Sensor - R5</td>
			<td>Vishay</td>
			<td>CRCW040210K0FKEDC</td>
			<td>10 kOhm 0402 resistor</td>
		</tr>
		<tr>
			<td>Sensor - X1</td>
			<td>ABRACON</td>
			<td>ABM8W-13.4916MHZ-8-J2Z-T3</td>
			<td>3.2 x 2.5 mm 13.4916 MHz 8 pF crystal</td>
		</tr>
		<tr>
			<td>Titanium wire</td>
			<td>Sigma-Aldrich</td>
			<td>GF36846434</td>
			<td>0.125 mm titanium wire</td>
		</tr>
		<tr>
			<td>Vector network analyzer</td>
			<td>mini RADIO SOLUTIONS</td>
			<td>miniVNA Tiny</td>
			<td>Other vector network analyzers can be used - the required operation frequency is 300&#8211;500 MHz, resolution bandwidth equal or lower than 1 MHz, output power of no more than 0 dBm and dynamic range preferably better than 60 dB for the receiving front-end</td>
		</tr>
	</tbody>
</table>

construction of a wireless-enabled endoscopically implantable sensor for ph monitoring with zero-bias schottky diode-based receiver

病理性反流的动态 pH 值监测是观察症状与食道暴露于酸性或非酸性反流物之间关系的机会。本文介绍了一种开发、制造和植入微型无线pH传感器的方法。该传感器设计为使用单个止血夹在内窥镜下植入。此外，还构建并测试了基于零偏置肖特基二极管的完全无源基于整流罩的接收器。为了构建该器件，使用了两层印刷电路板和现成的组件。带有集成模拟外设的微型微控制器用作离子敏感场效应晶体管（ISFET）传感器的模拟前端，并生成数字信号，该信号通过幅度移位键控发射器芯片传输。该设备由两个原碱性电池供电。植入式装置的总体积为0.6 cm3 ，重量为1.2克，其性能在 离体 模型（猪食道和胃）中得到验证。接下来，构建了一种基于小尺寸的无源矫直仪接收器，该接收器可以轻松集成到外部接收器或植入式神经刺激器中，并证明可以在靠近植入物（20厘米）时接收来自植入物的RF信号。传感器体积小，可提供连续的pH监测，同时将食道阻塞降至最低。该传感器可用于常规临床实践，用于24/96小时食管pH监测，而无需插入鼻导管。接收器的"零功率"特性还允许使用传感器对微型食管下括约肌神经刺激装置进行自动 体内 校准。基于传感器的主动控制支持开发高级算法，以最大限度地减少使用的能量，从而实现理想的临床结果。这种算法的一个例子是用于胃食管反流病（GERD）按需神经刺激治疗的闭环系统。

成功构建了一个能够自主pH传感和无线传输pH值的设备，如图8所示。构造的设备是一个微型模型;它重1.2克，体积为0.6厘米3。近似尺寸为 18 毫米 x 8.5 毫米 x 4.5 毫米。如图15、图16和图17所示，可以用单个止血夹将食管下括约肌植入附近;无需特殊配件。植入传感器的解剖食道的详细视图如?...

Watch this Scientific Journal Video about Construction of a Wireless-Enabled Endoscopically Implantable Sensor for pH Monitoring with Zero-Bias Schottky Diode-based Receiver at JoVE.com

Construction of a Wireless-Enabled Endoscopically Implantable Sensor for pH Monitoring with Zero-Bias Schottky Diode-based Receiver

该手稿介绍了一种微型植入式pH传感器，具有ASK调制无线输出以及基于零偏置肖特基二极管的完全无源接收器电路。该解决方案可用作开发 体内 校准电刺激治疗设备和动态pH监测的基础。

构建一种无线内窥镜植入式传感器，用于使用基于零偏置肖特基二极管的接收器进行pH监测

Ambulatory pH monitoring of pathological reflux is an opportunity to observe the relationship between symptoms and exposure of the esophagus to acidic or ...

该协议展示了无线植入式pH传感器的制造，该传感器将数据传输到完全无源接收器，从而能够非常节能地将数据从一个植入式设备传输到另一个植入式设备。传感器可以手工制造，也可以采用常用技术制造。接下来，数据传输方法可以直接在不同植入式设备的开发中重复使用。在每一步之后彻底检查无线pH传感器至关重要。用于制造其组件的组件非常小，在制造过程中可能会发生短路或错位。首先，将安装在PCB上的ISFET pH传感器放在平坦的表面上，然后将15毫米的氟化乙烯丙烯涂层电缆焊接到pH传感器的可焊电极上，而不会污染染料和带有助焊剂的PCB。混合至少两毫升的双组分环氧树脂以封装焊接的电极，然后使用黑色不透明环氧树脂进行后续检查。观察暴露在环境中的传感器部件在没有不透明环氧树脂的情况下的易見性。将混合的环氧树脂转移到带有0.5毫米平端针的一毫升注射器中，并用环氧树脂涂覆pH传感器的焊接区域，确保整个PCB电极区域和裸露的导线的涂层。在显微镜下检查涂层区域是否有任何未涂层的裸露金属部件。重复未涂覆金属的涂层过程后，将导线修剪到长度和角度，然后用焊料涂覆两端以避免磨损。将带有组件的PCB置于面朝上的位置后，将焊膏涂在所有暴露的镀金焊盘上。接下来，使用镊子放置无源和有源元件。焊接并冷却到室温后，在显微镜下检查PCB以验证元件和短路的位置。将固件编程到微控制器，并按照文中所述设置编程软件。接下来，将编程器设置为以大约2.5伏的电压为设备供电。然后在编程后对五根导线进行脱焊。将两个电池座焊接到 PCB 的另一部分。接下来，将pH传感器组件焊接到PCB的端子上，然后将两节AG1电池插入电池座。制备环氧树脂后，如前所述用环氧树脂封装设备。让环氧树脂在室温下固化。用一滴快速固化的环氧树脂将线钩连接到设备上。在室温下固化后，pH传感器可以位于可植入装置的左下角。使用焊枪焊接组件。要再次制造矫正接收器或在没有接收器匹配的情况下继续，请使用此处提供的组件值，并在下一步中跳过S11 Smith图表的记录。否则，请将 SMA 连接器焊接到 PCB 上。将矢量网络分析仪输入附加到 SMA 连接器。记录直肠的S11史密斯图。观察响应并记录阻抗。使用阻抗匹配计算器软件确定匹配元件的值。焊接阻抗匹配元件，并在显微镜下检查短路和元件位置。再次用频谱分析仪测量后，确认电压驻波比在300至500兆赫兹之间。否则，请使用不同的匹配组件重复上述步骤。在电池插入 24 小时后激活设备后，通过观察示波器中显示的信号来检查传感器的输出。制备pH 4、pH 7、pH 10的2%盐酸溶液和100毫摩尔缓冲溶液。将胶囊浸没在每个烧杯中，并记录至少三个样品。测量第二和第三脉冲之间的周期。在提供的电子表格中填写后，使用电子表格确定pH传感器的校准系数。在制备胃和食道长段的离体内窥镜猪模型后，用止血夹将传感器从外部抓取。以标准方式将带有传感器的内窥镜插入夹子中。将夹子与传感器一起靠近食管下括约肌放置后，将内窥镜对着食管壁旋转，打开夹子，然后向食管壁推。合上并松开夹子。当传感器保持在所需位置的食管壁上时，取出内窥镜。将接收器放置在植入式传感器的10厘米范围内。将50毫升具有不同pH值的溶液注入食道中，并观察传感器响应的变化。每次注射后收回内窥镜，并在注射后不早于30秒读取该值，并使用电子表格计算传感器测量的pH值。在具有不同pH值的注射溶液之间用100毫升去离子水冲洗食道。当无源矫正接收器放置在pH传感设备附近时，在设备发射时观察到明显的电压尖峰。前两个短脉冲是同步脉冲。第二个和第三个脉冲之间的时间线性转换为传感器所承受环境的pH值。基于使用 pH 4 和 pH 10 缓冲液进行的简单两点校准，传感器返回稳定且可重复的 pH 值读数。在溶液和烧杯中测试时，误差的均值和标准差分别为0.25和0.30，在离体模型中分别为0.31和0.36。具有活动GSM呼叫的移动电话天线对从传感器接收数据的影响只有很小的负面影响，如电话边缘和接收器之间的20厘米，10厘米和5厘米距离所示。必须正确完成和检查传感器的封装，以延长植入时设备的使用寿命。接下来，正确放置止血夹至关重要。这项研究通过创建一种节能的方式来传输数据，特别是从接收器的角度来看，为植入式设备的无线网络的发展铺平了道路。

Research

JoVE Journal

Bioengineering

Biomolecular Detection employing the Interferometric Reflectance Imaging Sensor (IRIS)

Biomolecular Detection employing the Interferometric Reflectance Imaging Sensor IRIS

生物分子检测的干涉反射成像传感器（IRIS）

The sensitive measurement of biomolecular interactions has use in many fields and industries such as basic biology and microbiology, ...

科研

生物工程

Monitoring Protein Adsorption with Solid-state Nanopores

监测与固态纳米孔蛋白质吸附

Solid-state nanopores have been used to perform measurements at the single-molecule level to examine the local structure and flexibility of nucleic acids ...

Hollow Microneedle-based Sensor for Multiplexed Transdermal Electrochemical Sensing

复透皮电化学传感的空心微针为基础的传感器

The development of a minimally invasive multiplexed monitoring system for rapid analysis of biologically-relevant molecules could offer individuals ...

Mass Cytometry: Protocol for Daily Tuning and Running Cell Samples on a CyTOF Mass Cytometer

质量流式细胞术：协议，每日调整和执行细胞的样品上一个CyTOF的质量流式细胞仪

In recent years, the rapid analysis of single cells has commonly been performed using flow cytometry and fluorescently-labeled antibodies. However, the ...

Tissue Engineering: Construction of a Multicellular 3D Scaffold for the Delivery of Layered Cell Sheets

组织工程：建设多细胞三维支架的层状细胞片交货

Many tissues, such as the adult human hearts, are unable to adequately regenerate after damage.2,3 Strategies in tissue engineering propose innovations to ...

Construction and Characterization of a Novel Vocal Fold Bioreactor

一种新型声带生物反应器的构建与鉴定

In vitro engineering of mechanically active tissues requires the presentation of physiologically relevant mechanical conditions to cultured cells. To ...

Biomembrane Fabrication by the Solvent-assisted Lipid Bilayer (SALB) Method

Biomembrane Fabrication by the Solvent-assisted Lipid Bilayer SALB Method

生物膜制作的溶剂辅助脂质双分子层（SALB）方法

In order to mimic cell membranes, the supported lipid bilayer (SLB) is an attractive platform which enables in vitro investigation of membrane-related ...

Real Time Monitoring of Intracellular Bile Acid Dynamics Using a Genetically Encoded FRET-based Bile Acid Sensor

细胞内胆汁酸动态实时监控使用遗传编码的FRET为基础的胆汁酸传感器

F&#246;rster Resonance Energy Transfer (FRET) has become a powerful tool for monitoring protein folding, interaction and localization in single cells. ...

Extraction of Plant-based Capsules for Microencapsulation Applications

基于植物的提取胶囊微胶囊化应用

Microcapsules derived from plant-based spores or pollen provide a robust platform for a diverse range of microencapsulation applications. Sporopollenin ...

Construction and Setup of a Bench-scale Algal Photosynthetic Bioreactor with Temperature, Light, and pH Monitoring for Kinetic Growth Tests

用于动态生长测试的温度，光照和pH监测的台式藻类光合生物反应器的构建和设置

The optimal design and operation of photosynthetic bioreactors (PBRs) for microalgal cultivation is essential for improving the environmental and economic ...