Name: gelatin methacryloyl granular hydrogel scaffolds: high-throughput microgel fabrication, lyophilization, chemical assembly, and 3d bioprinting
Uploaded: 2022-12-09T15:00:00
Description: Watch this Scientific Journal Video about Gelatin Methacryloyl Granular Hydrogel Scaffolds: High-throughput Microgel Fabrication, Lyophilization, Chemical Assembly, and 3D Bioprinting at JoVE.com

作者要感谢宾夕法尼亚州立大学（宾夕法尼亚州立大学）化学工程系的研究支持专家T. Pond，宾夕法尼亚州立大学纳米制造实验室的工作人员以及Partillion Bioscience的J. de Rutte博士关于纳米制造过程的帮助和讨论。A. Sheikhi感谢材料研究所（MRI）和工程材料物质学院在人类水平种子基金，生活多功能材料系统融合中心（LiMC2）和卓越集群生活，适应性和能源自主材料系统（livMatS）生活多功能材料合作研究种子资助计划，以及宾夕法尼亚州立大学的启动基金的支持。本出版物中报告的研究得到了美国国立卫生研究院（NIH）国家生物医学成像和生物工程研究所（NIBIB）的部分支持，奖励号为R56EB032672。

注意：有关本协议中使用的所有材料、仪器和试剂的详细信息，请参阅 材料表 。
1. 凝胶MA合成
注意：GelMA合成应在化学通风橱中进行，并应始终使用适当的个人防护设备（PPE）。
<ol><li>将200mL的Dulbecco磷酸盐缓冲盐水（DPBS，1x）加入锥形瓶中，并将溶液加热至达到50°C。 用铝箔盖住烧瓶以防止蒸发。</li>
	<li>在50°C下向DPBS溶液中...

<ol>
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M., Koh, J., Di Carlo, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Scalable+high-throughput+production+of+modular+microgels+for+in+situ+assembly+of+microporous+tissue+scaffolds.">Scalable high-throughput production of modular microgels for in situ assembly of microporous tissue scaffolds.</a> Advanced Functional Materials. 29 (25), 1900071 (2019).</li><li>Sheikhi, 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=Modular+microporous+hydrogels+formed+from+microgel+beads+with+orthogonal+thermo-chemical+responsivity:+Microfluidic+fabrication+and+characterization.">Modular microporous hydrogels formed from microgel beads with orthogonal thermo-chemical responsivity: Microfluidic fabrication and characterization.</a> MethodsX. 6, 1747-1752 (2019).</li><li>Van Den Bulcke, A. I., 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=Structural+and+rheological+properties+of+methacrylamide+modified+gelatin+hydrogels.">Structural and rheological properties of methacrylamide modified gelatin hydrogels.</a> Biomacromolecules. 1 (1), 31-38 (2000).</li><li>Qazi, T. H., 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=Anisotropic+rod-shaped+particles+influence+injectable+granular+hydrogel+properties+and+cell+invasion.">Anisotropic rod-shaped particles influence injectable granular hydrogel properties and cell invasion.</a> Advanced Materials. 34 (12), 2109194 (2022).</li><li>Highley, C. B., Song, K. H., Daly, A. C., Burdick, J. 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明胶及其衍生物是HMP制造中最常用的基于蛋白质的生物材料。使用步进乳化微流体装置可以克服通量与粒径单分散性权衡的挑战。这些装置每小时能够形成超过4000万个液滴，变异系数小于5%27。在本文中，我们讨论了含有GelMA溶液的液滴的微细加工，然后将其转化为GelMA HMP，粉末，GHS和NGB。
GelMA的热响应性使微流体的HMP制造和稳定变得简单。在高于UCST的温度?...

组装HMP构建块以形成组织工程支架在过去几年中获得了极大的关注1。通过HMP组件制造的GHS与散装同类产品相比具有独特的性能，包括源自离散构建块之间的空隙的细胞级微孔隙。其他特性，如注射性、模块化和刚度与孔隙率的解耦，使 GHS 成为增强组织修复和再生的有前途的平台2.不同的生物材料已被用于GHS制造，包括合成PEG基聚合物3，4和多糖，如藻酸盐5和透明质酸6，7。在天然衍生聚合物中，用于GHS制造的最常见的基于蛋白质的生物聚合物是GelMA8，9，10，11，这是一种可交联，生物相容性，生物粘附性和可生物降解的生物材料12，13。
HMP可以通过间歇乳化8、流动聚焦14、15或分步乳化9、11微流体装置、共混16或复合聚结17、18来制备。通常，制造吞吐量和HMP单分散性之间存在权衡。例如，混合技术产生不规则形状和高度分散的HMP。 间歇乳化或复杂凝聚能够生产大量多分散球形HMP。 聚焦流动微流体装置已被用于制造变异系数为<5%的高度单分散液滴，但通量显着降低。在分步乳化微流体器件中，高度并行化的步骤能够实现单分散HMP的高通量制造19。
甲基丙烯酰改性明胶 （GelMA） HMP 构建块具有热响应性和（光）化学交联性，可实现轻松的 GHS 制造20。当冷却到临界溶液温度（UCST）21以下（例如，在4°C下）时，含有GelMA溶液的液滴转化为物理交联的HMP。然后利用外力（例如，通过离心）填充这些 HMP 构建块以产生卡住的微凝胶悬浮液。通过（光）化学交联在相邻的HMP之间建立颗粒间链接，以形成机械坚固的GHS14。GHS最重要的特性之一是微孔率，使体外细胞易于渗透11，并增强体内组织向内生长22。HMP的三维（3D）生物打印通常使用紧密包装的微凝胶悬浮液进行，这会影响微孔23。
我们最近开发了一类基于GelMA微凝胶的界面纳米工程的新型颗粒生物墨水，通过吸附带异质电荷的纳米颗粒 ， 然后纳米颗粒可逆自组装。该策略使松散包装的微凝胶剪切产量和挤出3D可生物打印，从而保留了增材制造的GHS11的微尺度孔隙率。本文介绍了高通量 GelMA 液滴制造方法、将这些液滴转化为物理交联的 HMP、使用可重悬粉末制造 GelMA HMP、GelMA GHS 形成、GelMA 纳米工程颗粒生物墨水 （NGB） 制备和 3D 生物打印。

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>1H,1H-perfluoro-1-octanol</td>
			<td>Alfa Aesar, MA, USA</td>
			<td>B20156-18</td>
			<td>98% purity</td>
		</tr>
		<tr>
			<td>Biopsy punch</td>
			<td>Integra Miltex, NY, USA</td>
			<td>33-31A-P/25</td>
			<td>1.5 mm Biopsy Punch with Plunger System</td>
		</tr>
		<tr>
			<td>Blunt needle</td>
			<td>SANANTS</td>
			<td>30-002-25</td>
			<td>25 G</td>
		</tr>
		<tr>
			<td>Bruker Avance NEO 400 MHz</td>
			<td>400 MHz Bruker NEO, MA, USA</td>
			<td></td>
			<td>NMR device</td>
		</tr>
		<tr>
			<td>Centrifuge</td>
			<td>Eppendorf, Germany</td>
			<td>5415 C</td>
			<td></td>
		</tr>
		<tr>
			<td>Centrifuge tube</td>
			<td>Celltreat, MA ,USA</td>
			<td>229423</td>
			<td></td>
		</tr>
		<tr>
			<td>Coffee filters</td>
			<td>BUNN, IL, USA</td>
			<td>20104.0006</td>
			<td>BUNN 8-12 Cup Coffee Filters, 6 each, 100 ct</td>
		</tr>
		<tr>
			<td>Desiccator</td>
			<td>Thermo Scientific</td>
			<td>5311-0250</td>
			<td>Nalgene Vacuum Desiccator, PC Cover and Body, 280 mm OD</td>
		</tr>
		<tr>
			<td>Deuterium oxide</td>
			<td>Sigma, MA, USA</td>
			<td>151882</td>
			<td></td>
		</tr>
		<tr>
			<td>Dialysis membrane (12-14 kDa)</td>
			<td>Spectrum Laboratories, NJ, USA</td>
			<td>08-667E</td>
			<td></td>
		</tr>
		<tr>
			<td>Dulbecco&#39;s phosphate buffered saline (DPBS, 1x)</td>
			<td>Sigma, MA, USA</td>
			<td>56064C-10L</td>
			<td>dry powder, without calcium, without magnesium, suitable for cell culture</td>
		</tr>
		<tr>
			<td>Erlenmeyer flask</td>
			<td>Corning, NY, USA</td>
			<td>4980</td>
			<td>Corning PYREX&#160;</td>
		</tr>
		<tr>
			<td>Ethanol</td>
			<td>VWR, PA, USA</td>
			<td>89125-188</td>
			<td>Koptec 200 proof</td>
		</tr>
		<tr>
			<td>External thread cryogenic vials (cryovials)</td>
			<td>Corning, NY, USA</td>
			<td>430659</td>
			<td></td>
		</tr>
		<tr>
			<td>Freeze dryer</td>
			<td>Labconco, MO, USA</td>
			<td>71042000</td>
			<td>Equipped with vacuum pump (Catalog# 7587000)</td>
		</tr>
		<tr>
			<td>Gelatin powder</td>
			<td>Sigma, MA, USA</td>
			<td>G1890-5100G</td>
			<td>Type A from porcine skin, gel strength ~300 g Bloom</td>
		</tr>
		<tr>
			<td>Glass microscope slides</td>
			<td>VWR, PA, USA</td>
			<td>82027-788</td>
			<td></td>
		</tr>
		<tr>
			<td>Hotplate</td>
			<td>FOUR E&#39;S SCIENTIFIC</td>
			<td>MI0102003</td>
			<td>5 inch Magnetic Hotplate Stirrer Max Temp 280 &#176;C/536 &#176;F&#160;</td>
		</tr>
		<tr>
			<td>Kimwipes</td>
			<td>Fischer scientific, MA, USA</td>
			<td>06-666</td>
			<td></td>
		</tr>
		<tr>
			<td>KMPR 1000 negative photoresist series</td>
			<td>Kayaku Advanced Materials, MA, USA</td>
			<td>121619</td>
			<td>KMPR1025 and KMP1035 are included</td>
		</tr>
		<tr>
			<td>LAPONITE XLG</td>
			<td>BYK USA Inc., CT, USA</td>
			<td>2344265</td>
			<td></td>
		</tr>
		<tr>
			<td>Lithium phenyl-2,4,6-trimethylbenzoylphosphinate (LAP)</td>
			<td>Sigma, MA, USA</td>
			<td>900889-1G</td>
			<td>&#62;95%</td>
		</tr>
		<tr>
			<td>Luer-Lok connector</td>
			<td>BD, NJ, USA</td>
			<td>BD 302995&#160;</td>
			<td></td>
		</tr>
		<tr>
			<td>MA/BA Gen4-Serie Mask- und Bond-Aligner</td>
			<td>S&#220;SS MicroTeck, German</td>
			<td></td>
			<td>Nanofabrication device</td>
		</tr>
		<tr>
			<td>Methacylate anhydride</td>
			<td>Sigma, MA, USA</td>
			<td>276685-100ML</td>
			<td>contains 2,000&#160;ppm topanol A as inhibitor, 94%</td>
		</tr>
		<tr>
			<td>Milli-Q water</td>
			<td>Millipore Corporation, MA, USA</td>
			<td>ZRQSVR5WW</td>
			<td>electrical resistivity &#8776; 18 M&#937; at 25 &#176;C, Direct-Q 5 UV Remote Water Purification System</td>
		</tr>
		<tr>
			<td>Novec 7500 engineering fluid</td>
			<td>3M, MN, USA</td>
			<td></td>
			<td>3M ID&#160;7100003723</td>
		</tr>
		<tr>
			<td>Oven</td>
			<td>VWR, PA, USA</td>
			<td>VWR-1410</td>
			<td>1410 Vacuum Oven</td>
		</tr>
		<tr>
			<td>Parafilm</td>
			<td>Fischer scientific, MA, USA</td>
			<td>HS234526C</td>
			<td></td>
		</tr>
		<tr>
			<td>Pasteur pipette</td>
			<td>VWR, PA, USA</td>
			<td>14673-010</td>
			<td></td>
		</tr>
		<tr>
			<td>Petri dish</td>
			<td>VWR, PA, USA</td>
			<td>25384-092</td>
			<td>polystyrene</td>
		</tr>
		<tr>
			<td>Pico-Surf</td>
			<td>Sphere Fluidics, UK</td>
			<td>C022</td>
			<td>(5% (w/w) in Novec 7500)</td>
		</tr>
		<tr>
			<td>Pipette</td>
			<td>VWR, PA, USA</td>
			<td>89079-970</td>
			<td></td>
		</tr>
		<tr>
			<td>Pipette tips</td>
			<td>VWR, PA, USA</td>
			<td>87006-060</td>
			<td></td>
		</tr>
		<tr>
			<td>Plasma cleaner chamber</td>
			<td>Harrick Plasma, NY, USA</td>
			<td>PDC-001-HP&#160;</td>
			<td></td>
		</tr>
		<tr>
			<td>Polydimethylsiloxane</td>
			<td>Dow Corning, MI, USA</td>
			<td>&#160;2065623</td>
			<td>SYLGARD 184 Silicone Elastomer Kit</td>
		</tr>
		<tr>
			<td>Positive displacement pipette</td>
			<td>Microman E M100E, Gilson, OH, USA</td>
			<td>M100E</td>
			<td></td>
		</tr>
		<tr>
			<td>Silicon wafers</td>
			<td>UniversityWafer, MA, USA</td>
			<td>452/1196</td>
			<td>4-inch mechanical grade</td>
		</tr>
		<tr>
			<td>Spatula</td>
			<td>VWR, PA, USA</td>
			<td>231-0104</td>
			<td>Disposable</td>
		</tr>
		<tr>
			<td>SU-8&#160;</td>
			<td>Kayaku Advanced Materials, MA, USA</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Syringe pump</td>
			<td>Harvard Apparatus, MA, USA</td>
			<td>70-2001</td>
			<td>PHD 2000</td>
		</tr>
		<tr>
			<td>Trichloro(1H,1H,2H,2H-perfluorooctyl)silane</td>
			<td>Millipore Sigma, MA, USA</td>
			<td>448931-10G</td>
			<td>97%</td>
		</tr>
		<tr>
			<td>Tygon tubings</td>
			<td>Saint-globain, PA, USA</td>
			<td>AAD04103&#160;</td>
			<td></td>
		</tr>
		<tr>
			<td>UV light&#160;</td>
			<td>QUANS</td>
			<td></td>
			<td>Voltage: 85 V-265 V AC / Power: 20 W</td>
		</tr>
		<tr>
			<td>Vacuum filtration unit</td>
			<td>VWR, PA, USA</td>
			<td>10040-460</td>
			<td>0.20 &#181;m</td>
		</tr>
		<tr>
			<td>Vortex</td>
			<td>Fischer scientific, USA</td>
			<td>14-955-151</td>
			<td>Mini Vortex Mixer</td>
		</tr>
	</tbody>
</table>

gelatin methacryloyl granular hydrogel scaffolds: high-throughput microgel fabrication, lyophilization, chemical assembly, and 3d bioprinting

通过组装水凝胶微粒（HMP） 制造的 颗粒水凝胶支架（GHS）的出现使微孔支架能够原 位形成。与传统的块状水凝胶不同，GHS中互连的微尺度孔有助于与降解无关的细胞浸润以及氧气，营养和细胞副产物的转移。甲基丙烯酰基改性明胶（GelMA）是一种（光）化学可交联的蛋白质基生物聚合物，含有细胞粘合剂和可生物降解的部分，已被广泛用作细胞响应/指导性生物材料。将散装GelMA转化为GHS可能会为组织工程和再生带来大量机会。在本文中，我们展示了高通量GelMA微凝胶制造，转化为可重悬的干燥微凝胶（微气凝胶），通过微凝胶的化学组装 形成 GHS以及用于挤出生物打印的颗粒生物墨水制造的过程。我们展示了通过冷却和光交联的顺序物理化学处理如何能够形成机械坚固 的 GHS。当光线无法接触时（例如，在深层组织注射期间），可以使用谷氨酰胺转移酶通过酶促交联 进行 生物正交组装单独交联的 GelMA HMP。最后，通过多相带电纳米颗粒的界面自组装 ，证明了 低HMP堆积密度下微孔GHS的三维（3D）生物打印。

GelMA是通过明胶与MA的反应合成的，如图 1A所示。通过调整反应条件，如MA浓度，得到不同程度的MA取代。为了量化MA取代的程度， 通过1H NMR波谱评估GelMA（图1B）。在~5-6 ppm的化学位移处具有代表性峰的乙烯基官能团证实了明胶成功合成GelMA。透析和无菌过滤后的反应收率为>70%（mg的GelMA/mg的明胶）。液滴/微凝胶制备产率为~100%。可以使用?...

Watch this Scientific Journal Video about Gelatin Methacryloyl Granular Hydrogel Scaffolds: High-throughput Microgel Fabrication, Lyophilization, Chemical Assembly, and 3D Bioprinting at JoVE.com

Gelatin Methacryloyl Granular Hydrogel Scaffolds: High-throughput Microgel Fabrication, Lyophilization, Chemical Assembly, and 3D Bioprinting

本文介绍了使用微流体装置制造高通量明胶甲基丙烯酰基微凝胶的协议，将微凝胶转化为可重悬粉末（微气凝胶），微凝胶的化学组装以形成颗粒水凝胶支架，以及开发具有保留微孔隙率的颗粒水凝胶生物墨水用于3D生物打印。

明胶甲基丙烯酰基颗粒水凝胶支架：高通量微凝胶制造、冻干、化学组装和 3D 生物打印

The emergence of granular hydrogel scaffolds (GHS), fabricated via assembling hydrogel microparticles (HMPs), has enabled microporous scaffold formation ...

细胞外基质或ECM数字水凝胶微粒可用作支架制造的构建块。该协议展示了明胶甲基丙烯酰或GelMA水凝胶微粒的制造，纯化，冻干，照片组装和3D生物打印。GelMA是一种光化学，可交联，基于蛋白质的生物聚合物，含有细胞粘合剂和可生物降解的部分，已被广泛用作细胞响应和指导性的生物材料。与传统的散装水凝胶相比，GelMA颗粒水凝胶支架是微孔的，可以根据构建块尺寸进行快速细胞浸润。GelMA颗粒水凝胶支架可能为在廉价平台和再生工程上对厚组织，器官和疾病的3D生物打印开辟新的机会。首先，将 10 毫克 LAP 加入 10 毫升 DPBS 中以制备 0.1% 光引发剂溶液。用铝箔包裹溶液，使其免受光照，并贴上标签。接下来，将所需量的GelMA溶解在光引发剂溶液中。将铝箔包裹的溶液放入 37 摄氏度的烤箱中一小时，以获得澄清的溶液。为了制备油相，在工程流体中制备2%生物相容的表面活性剂溶液。将 Tygon 管插入 PDMS 设备的入口和出口，然后将 25 号钝针插入 Tygon 管的另一端用于入口。将设备放在显微镜下，并使用吹风机或空间加热器将环境保持在约40摄氏度的温度。将水溶液和油溶液装入连接到设备的单独注射器中。以每分钟160微升的流速启动油相注射泵。油充满通道后，以每分钟 80 微升的速度启动水相。在显微镜下检查液滴的形成。将液滴收集在容器中，并通过光学显微镜成像在成像室中对其进行评估。将液滴保持在4摄氏度过夜，同时保护它们免受光照，以启动GelMA微凝胶的物理交联并将液滴转化为稳定的微凝胶。为了实施微工程乳液到粉末MEtoP方法，使用耐热微量离心管或冷冻管收集工程流体中的物理交联微凝胶。用实验室擦拭布和胶带密封开口管。将物理交联的微凝胶在液氮中深度冷冻10分钟以进行冻干。冻干后，将获得固体粉末。在冻干粉末中加入一毫升冷却的0.1%光引发剂溶液，在4摄氏度下制成微凝胶悬浮液。将涡旋混合物以3， 000g离心15秒。弃去上清液后，使用外置活塞式移液器将包装好的微凝胶悬浮液转移到模具中，并将其暴露在400纳米波长的光下，强度为每平方厘米15毫瓦60秒，形成颗粒状水凝胶支架或GHS。对于400微凝胶悬浮液，向物理交联的GelMA微凝胶中加入等量的冰冷PFO溶液，20%的工程流体。然后将涡旋混合物以300g离心15秒，并通过移液从GelMA微凝胶中除去油相。然后在微凝胶悬浮液中加入400微升冰冷的0.1%光引发剂溶液。将涡旋溶液以300g离心15秒后，弃去油。重复光引发剂溶液加入和离心的步骤，但这次以3， 000g离心，并弃去填充的GelMA微凝胶的上清液。将包装好的GelMA微凝胶转移到模具中，然后进行光照以形成GHS。将100毫克纳米片粉加入3毫升冰冷的超纯水中，形成3.33%的纳米颗粒分散体。在四摄氏度的冰箱内剧烈涡旋分散体15分钟，以去除聚集的纳米颗粒。适当剥离的纳米颗粒产生清晰的分散体。将 50 毫克 LAP 溶解在 5 毫升冰冷的超纯水中，制备 1% 光引发剂储备溶液。然后将333微升1%光引发剂溶液加入剥落的纳米颗粒分散体中，并将其包裹在铝箔中以防止环境光。涡旋混合物一分钟以混合纳米颗粒分散体和光引发剂。将冰冷的PFO（20%工程流体）以一比一的体积比添加到物理交联的GelMA微凝胶中。将涡旋混合物以300g离心15秒后，丢弃含有表面活性剂的油相。将冰冷的、补充LAP的纳米颗粒分散体添加到洗涤的GelMA微凝胶中。在3， 000g离心15秒后，弃去底部剩余的油和上清液分散液。将悬浮液储存在四摄氏度，同时使用铝箔保护其避光一天，以产生产品GelMA纳米工程颗粒生物墨水或NGB。第二天，将NGB装入三毫升注射器中。用盖子和封口膜密封装载的注射器，并以200g进行脉冲离心以除去滞留的空气。使用母-母鲁尔锁连接器将生物墨水转移到三毫升墨盒中。再次以 200g 的速度短暂离心滤芯以去除滞留的空气，并在使用前将 NGB 保持在 4 摄氏度。接下来，将制备好的鼠成纤维细胞悬液装入三毫升注射器中。使用母-母鲁尔锁连接器耦合NGB和细胞加载注射器，并通过来回推动40次轻轻混合内容物。通过将喷嘴装入三毫升打印头，使用带有标准锥形喷嘴的适当生物打印机打印NGB或含有细胞的NGB。保持打印床温度低于10摄氏度，并优化速度和背压等参数。选择所需的 gcode 或 STL 文件。然后为配备标准锥形喷嘴的气动三毫升注射器选择基材和喷嘴类型。使用设备指南校准生物打印机，并开始打印以获得3D结构。MEtoP技术通过低压冷冻干燥生产可重悬的干燥微凝胶粉末，同时保护微凝胶免受聚集和严重变形。SEM图像显示，与传统冻干观察到的聚集相比，使用该技术的干燥GelMA微粒在冻干后保持其球形。使用高分子量荧光染料对GelMA，GHS和NGB的微孔表征显示了相互连接的微尺度空隙空间。此外，使用自定义编写的MATLAB脚本评估的荧光图像检测到孔隙。空隙分数和中位数孔等效直径测量显示没有显着差异，证明了使用NGB的3D打印支架中微尺度孔的可用性和互连性。通过悬挂丝长度测量，NGB支架优于紧密和松散包装的GelMA微凝胶，表明NGB的长度大于填充微凝胶。松散包装的微凝胶不会产生细丝。一个空心圆柱体被3D打印，整个结构暴露在光线下进行光交联。打印结构被物理固定以显示形状、保真度和结构完整性。如果支架用于生物评估，例如，在充满细胞的生物打印中，请记住在特定条件下在生物安全柜下执行所有步骤。我们希望将颗粒水凝胶支架作为生物医学中新兴的生物材料平台的使用去市场化。

Research

JoVE Journal

Bioengineering

3D Hydrogel Scaffolds for Articular Chondrocyte Culture and Cartilage Generation

3D水凝胶支架的关节软骨细胞培养及软骨生成

Human articular cartilage is highly susceptible to damage and has limited self-repair and regeneration potential. Cell-based strategies to engineer ...

科研

生物工程

Bioprinting Cellularized Constructs Using a Tissue-specific Hydrogel Bioink

生物印刷细胞化构造使用组织特异性水凝胶生物油墨

Bioprinting has emerged as a versatile biofabrication approach for creating tissue engineered organ constructs. These constructs have potential use as ...

Bioprinting of Cartilage and Skin Tissue Analogs Utilizing a Novel Passive Mixing Unit Technique for Bioink Precellularization

Bioink Precellularization 无源混合装置打印软骨及皮肤组织类似物的应用

Bioprinting is a powerful technique for the rapid and reproducible fabrication of constructs for tissue engineering applications. In this study, both ...

Bioprintable Alginate/Gelatin Hydrogel 3D In Vitro Model Systems Induce Cell Spheroid Formation

Bioprintable Alginate/Gelatin Hydrogel 3D In Vitro Model Systems Induce Cell Spheroid Formation

Bioprintable 藻酸盐/明胶水凝胶 3D体外模型诱导细胞球形形成

The cellular, biochemical, and biophysical heterogeneity of the native tumor microenvironment is not recapitulated by growing immortalized cancer cell ...

3D Printed Porous Cellulose Nanocomposite Hydrogel Scaffolds

三维印刷多孔纤维素纳米复合水凝胶脚手架

This work demonstrates the use of three-dimensional (3D) printing to produce porous cubic scaffolds using cellulose nanocomposite hydrogel ink, with ...

Protocols of 3D Bioprinting of Gelatin Methacryloyl Hydrogel Based Bioinks

明胶美沙克里洛醇水凝胶生物油墨3D生物印刷方案

Gelatin methacryloyl (GelMA) has become a popular biomaterial in the field of bioprinting. The derivation of this material is gelatin, which is hydrolyzed ...

Preparation and Characterization of Graphene-Based 3D Biohybrid Hydrogel Bioink for Peripheral Neuroengineering

用于外周神经工程的石墨烯基3D生物杂化水凝胶生物墨水的制备与表征

Peripheral neuropathies can occur as a result of axonal damage, and occasionally due to demyelinating diseases. Peripheral nerve damage is a global ...

Interlinked Macroporous 3D Scaffolds from Microgel Rods

来自微凝胶棒的互连大孔3D支架

A two-component system of functionalized microgels from microfluidics allows for fast interlinking into 3D macroporous constructs in aqueous solutions ...

Synthesis of Strong Adhesive Hydrogel, Gelatin O-Nitrosobenzaldehyde

强粘性水凝胶明胶O-亚硝基苯甲醛的合成

Adhesive materials have become popular biomaterials in the field of biomedical and tissue engineering. In our previous work, we presented a new material - ...

Agarose Fluid Gels Formed by Shear Processing During Gelation for Suspended 3D Bioprinting

琼脂糖流体凝胶在凝胶过程中通过剪切处理形成，用于悬浮3D生物打印

The use of granular matrices to support parts during the bioprinting process was first reported by Bhattacharjee et al. in 2015, and since then, several ...