This work was supported by NIH-NIDCR IRO1DE019355 (MJ Yost, PI), and NSF-EPSCoR (EPS-0903795).

1.确定物中的胶原蛋白批次的百分比<ol><li>提取继先前公布的程序13的胶原蛋白。解冻的最低20ml的胶原蛋白。确定以操纵在形成的水凝胶，胶原浓度在批处理胶原固体的初始百分比。 <ol><li>切三块铝箔（约6×6厘米）中，并通过用25毫升烧杯的底部形状每一个作为锅。记录每个锅的重量。 </li><li>胶原的少量添加到每个平移和记录铝锅和胶原的总重量。添加0.5 - 0.8克胶原每个铝盘。 注意:在此步骤之后，有三个铝箔盘和每一个应当有胶原的量小。确保记录每个（总共3）空铝盘的重量和锅的加成胶原后的重量。 </li><li>使用F计算胶原的重量在每一个锅ollowing公式: 胶原蛋白的重量=潘和胶原蛋白的重量 - 潘重</li><li>放置持有在100℃下在烘箱中胶原24小时三个铝盘中。 </li><li> 24小时后，记录每个铝盘的重量和脱水的胶原蛋白。 </li><li>计算使用下面的等式脱水胶原的重量: 脱水的胶原蛋白的重量=平移和脱水的胶原蛋白的重量 - 潘重</li><li>计算的固体的百分比为三个样品，使用以下公式确定胶原固体浓度: <img alt="公式（2）" src="/files/ftp_upload/53578/53578eq2.jpg" /></li><li>计算使用胶原固体为三个样本的百分比批次的平均胶原固体含量。 注意:将要使用的胶原是留下水合胶原蛋白。脱水的胶原蛋白没有将被使用。 </li><li>确定胶原固体（我的百分比后该批nitial胶原浓度），继续使用剩余的水合胶原。使用经过校准的pH计的胶原批次的pH调节至3。 <ol><li>加入少量（每次2-5微升）12 N盐酸（HCl）的。保持冰在任何时候。不直接添加盐酸以胶原 - 酸添加到该管的一侧。加酸后，用锅铲酸推到胶原蛋白，迅速搅拌混合。 </li></ol></li><li>一旦它的pH值达到3，让胶原坐O / N在4℃。 </li></ol></li></ol> 2. BSA橡胶的制备<ol><li>制备按照下面所列的步骤的牛血清白蛋白（BSA）溶液。 <ol><li>制备2倍磷酸盐缓冲盐水液（PBS）中。添加两个PBS片剂至100毫升的水，使0.02M的PBS溶液。 </li><li>结合BSA的2倍的PBS来创建使用下列顺序的30％BSA溶液。 <ol><li>例如，为了使30％的BSA用30ml 2×PBS中，使用12.9克的BSA。添加2倍的PBS（例如，10ml）中的1/3到有搅拌棒的烧瓶中。添加BSA（如，6.45克BSA）在烧瓶1/2和使用刮刀，润湿干溶质。 </li><li>重复加入PBS中，然后BSA的这个过程，直到所有的溶质和溶剂在烧瓶中。用锅铲湿所有的溶质。它看起来像一些液体和团块的混合物。让它坐大约30分钟。 </li><li>然后，打开一个小周期的搅拌器，并确保周围有搅拌棒无团块。它应该采取90分钟得到解决方案的所有或者也可以在4℃下搅拌O / N。溶质全部溶解后，放置在20毫升注射器的溶液，并用0.20微米的注射器过滤器盖上。按下柱塞通过过滤器排出液体，并收集在一个新的管中的灭菌溶液。保存在4℃。 </li></ol></li><li>准备3％戊二醛soluti通过稀释无菌过滤2X PBS 25％戊二醛溶液。例如，10毫升3％戊二醛溶液，使用2个ml等于25％的戊二醛和8毫升2×PBS中。保存在4℃。 </li></ol></li></ol> 3.治疗模具 注:本文中所描述的原型采用的是定制的不锈钢Ÿ防霉片。模具包含一个流入和分别为4和3mm两个流出通道。首先，清洁模具，喷洒与不饱和猪油和消毒他们。按照以下描述的步骤制备的模具。 <ol><li>使用超声波仪，在35千赫的频率干净的不锈钢模具。放置模具在超声波仪，用水和冰淹没它们。保持模具冷在任何时候都超声波仪运行时。运行超声波仪90分钟2​​期。 <ol><li>每一个时期后，用针，以确保没有在鲁尔无重大锁定不锈钢或bRASS连接器。用肥皂和水清洗模具双方的整个表面。验证是否有在渠道上没有障碍。 </li></ol></li><li>放置模具，螺丝，和鲁尔锁定连接​​器在高压釜中袋和高压灭菌它。 </li><li>填补重视与市售猪油（混合脂肪酸脱模剂）的空气喷雾器一半的瓶子。更换一个普通盖瓶帽。将其放置在高压釜中袋和高压灭菌它。 注意:猪油用于促进该材料，就可以注射以后反应（BSA橡胶）的释放。不要把喷雾器瓶盖在autoclave-它会损坏内部密封。 </li><li>热身猪油45秒，直到它的明确和液体微波炉。螺杆空气喷涂机盖猪油瓶。盖连接的喷雾器。附加喷雾器在实验台上的气源。打开空气阀，并打开喷雾器的喷嘴，直到它开始润湿表面的纸巾。 </li><li>喷猪油垂直于模具表面，直到表面被完全覆盖。每一块被喷后，将它们放置在培养皿和密封。放置模具在4℃下2小时。 </li><li>继续进行由表面向UV光暴露30分钟以消毒该模具。将它们放回在4°C，直到他们准备好要反应注射。 </li></ol> 4. BSA橡胶反应注射 注:所有的材料和解决方案应保持低温，直到准备使用，以防止BSA橡胶过早凝固在接下来的步骤。 <ol><li>准备分配器交付BSA橡胶以下步骤模具。 <ol><li>消毒所有混合组分（二O形环，注射器帽，双注射器，混合尖端，和4:1分配器）通过暴露于UV光在聚合酶链反应（PCR）罩30分钟。 注意:PCR罩被使用，因为Ť他的过程涉及固定剂。这些化学物质不能在细胞/组织培养橱中使用，由于曝光和毒性的细胞的风险。包含UV光的任何其它罩将是合适的。 </li><li>放置在溶液保持器的尖端帽。 </li><li> BSA的比为1:在一个4进行混合和注射戊二醛。 30％BSA加入双注射器腔，将提供的解决方案的最高金额（这将需要大约4毫升填写）。确保留有足够的空间，以O形圈放置，以防止相邻的腔室的溢流和污染。 </li><li>加入3％戊二醛溶液到另一个房间（这将需要约1毫升填写）。请务必留出足够的空间放置O形环，以防止相邻室四溢和污染。 </li><li>放置在分配器中的双注射器。垂直倾斜组件使得注射器帽是在顶部。更换混合头帽。 </li><li>钪REW两个不锈钢模具拼在一起。 </li><li>将装配高压釜袋里面。 </li><li>以除去任何空气在分配器，将其保持在直立位置，并迅速挤压手柄一次，以释放与戊二醛混合波塞少量。然后迅速装上不锈钢Ÿ模具的鲁尔锁连接器连接到注射器尖端。 </li><li>持用左手和右侧的BSA的戊二醛混合物分配器不锈钢ý模具。通过按排出到高压釜袋的侧面，以确保内部的空隙填充有溶液交替覆盖各流出通道的左侧和右侧排气。然后，水平放置的模具和再次注入。 </li><li>从分离饮水机和地点该模具在25毫米的培养皿。 </li><li>放置封口膜周围的培养皿，以防止橡胶的脱水。 </li><li>放置在4℃冰箱O / N模具。 </li></ol></li></ol>注意:胶原应在所有时间的过程中被保持在冰上。 <ol><li>修改使用胶原固体的百分比胶原浓度。 <ol><li>通过调整用冷水初始浓度胶原蛋白使10毫升1.75％的胶原蛋白。 </li><li>使用校准pH计，调节用12N盐酸将pH至3。不直接添加盐酸到胶原的酸添加到该管的一侧。加酸后，用锅铲酸推入的胶原蛋白，迅速搅拌混合。 </li><li>权衡4克胶原在一个单独的锥形管中。 </li><li>离心胶原在4℃和9,343×g离心20-30分钟以除去空气。 </li><li>紫外线消毒细胞培养罩30分钟，并添加14微升粘连到4毫升胶原。这将导致10微克/微升的最终层粘连蛋白的浓度。注:层粘连蛋白将提供关于Structural完整性，附着力，并促进各种细胞应答。 </li><li>打开PCR紫外灯上20-30分钟用消毒罩之前。 </li><li>放置路厄锁盖，附加到20ml的注射器，在乙醇中2小时。然后，使其干燥，并放置在UV光。 </li><li>伽玛辐照胶原蛋白8.6分钟达到1200 cGy的。 注意:时间将取决于铯源的衰减。调整以达到相同的剂量的时间。 </li></ol></li></ol>对BSA橡胶6.Casting胶原蛋白<ol><li>以聚合胶原，使用8:1:1的比例（胶原:HEPES:MEM）中。下面的过程是基于一个初始4克酸化胶原（来自步骤5.1.8）的。 <ol><li>使在水中的0.2N的HEPES溶液，并通过加入1-5 1M氢氧化氢氧化钠（NaOH）溶液少量（1-5微升）将pH调节至9。使用校准pH计，监测每次加入后的溶液的pH值。保存在4℃或科EP冰上。 </li><li>打开组织培养罩的UV光20-30分钟进行消毒罩。 </li><li>蒸压钳，铲，手术刀和消毒。 </li><li>拌1.5的0.2N的HEPES（pH为9）和1.5的10倍的MEM毫升利用组织培养罩毫升。请一定要保持它在冰上旋涡其5秒后才能使用。存放在4℃或保持在冰上。 </li><li>消毒的PCR罩，开启UV光30分钟。 </li><li>放置在-20℃的12孔平板和一个20毫升注射器10分钟，或直至准备继续。注意:将所有材料冷待用。温度的增加导致过早胶原原纤维。 </li><li>喷雾所有管和孔板那将是在用70％乙醇罩，并让他们干灭菌。置于冰上20毫升注射器冷却以备后用。 </li><li>在PCR罩，打开不锈钢模具释放BSA橡胶和使用手术刀，切开BSA R的排气通道ubber模具。 </li><li>下的PCR罩中，打开无菌胶原管和加入1毫升的HEPES-MEM溶液（确保提取的HEPES-MEM溶液，这是很好的混合，并且没有固体沉淀之前）。 </li><li>使用无菌刮刀，调匀胶原蛋白和缓冲溶液。 </li><li>关闭并涡旋它迅速，以确保充分混合的水凝胶。 </li><li>转移到冷20毫升注射器。 </li><li>用一只手握住的BSA橡胶阱的内部，并使用其他分配一半胶原凝胶溶液到井的底部。 </li><li>使用无菌镊子，确保橡胶流入和流出的两端接触的侧面很好。 </li><li>倒入橡胶的顶部胶原溶液直至完全覆盖。 </li><li>确保BSA橡胶胶原内暂停，不存在任何气泡，尤其是靠近橡胶的端部。 </li><li>将机盖和包装封口膜周围的阱的周边。 </li><li>把在培养箱中1小时，在37℃。保持对PCR紫外光。 </li></ol></li><li>胶原聚合后，紫外线交联通过以下过程中的水凝胶。 注意:胶原的交联将使用其中可以控制能量的量的UV交联剂装置来完成。 <ol><li>打开UV交联剂和使用的能源与环境μJ630000 /厘米2照射空室。 </li><li>从培养箱中取出凝胶。 </li><li>喷雾手用乙醇，而且，在室内，迅速取下盖越好。 </li><li>关闭室和紫外线通过选择能量设置和照射630000μJ/ cm 2的交联水凝胶。 </li><li>交联循环后，关掉紫外线灯的PCR罩</li><li>喷雾手用乙醇和打开密室，迅速将盖放回孔板。移动孔板到PCR罩。 </li><li>使用无菌刮刀，轻轻拧松并从井中取出凝胶。翻转引擎盖下的凝胶以交联水凝胶的底部。重复步骤6.2.3和6.2.4。 </li></ol></li></ol> 7. BSA橡胶酶切<ol><li>为了具有中空胶原支架，除去BSA橡胶中的方式，不影响嵌在水凝胶的尺寸。该过程描述如下。 <ol><li>打开紫外光20-30分钟来灭菌组织培养罩。 </li><li>使0.25％的胰蛋白酶溶液的pH值7.8。例如，15毫升水，在50毫升锥形管中添加0.0376克胰蛋白酶。通过加入1M NaCl的少量（2-5微升）调节pH值至7.8。放置在20毫升注射器的溶液，并用0.20微米的注射器过滤器盖上。按下柱塞通过过滤器排出液体，并收集在一个新的管中的无菌溶液。 </li><li>放水浴，将温度设定为30C。 </li><li> 30分钟后，关掉紫外线灯。喷洒在将在罩中使用的所有管和材料乙醇。 </li><li>在不同的锥形管引擎盖下发生转移的胶原凝胶。 </li><li>周围添加3-5毫升（刚好足以覆盖凝胶）的0.25％胰蛋白酶溶液，pH值为7.8至每个管。 </li><li>密封用封口膜和涡轻管约1分钟。 </li><li>发生在30℃的水浴中15-24小时。而在水浴，轻轻频繁涡凝胶直到BSA的橡胶已被消化或从水凝胶中移除。 注意:为了确定是否波塞橡胶已被去除，或者将橡胶漂浮在胰蛋白酶溶液或有破旧件。必须有水凝胶内没有视觉暗区。 </li></ol></li><li>为了确保所有的BSA的橡胶和胰蛋白酶已经从水凝胶取出，如下所述冲洗。 <ol><li>打开PCR呼ð紫外线20-30分钟。 </li><li>准备Mosconas解决方案。在水结合氯化钾（KCl，28.6毫摩尔），（ 碳酸氢钠 ，11.9毫摩尔），葡萄糖（9.4毫摩尔）和（的NaH 2 PO 4，0.08毫摩尔）。调节pH值至7.4，用1M的NaOH或12M的HCl溶液。放置在20毫升注射器的溶液和使用0.20微米的注射器过滤器进行消毒的溶液中。 </li><li>喷雾用乙醇一切之前将它们放置在引擎盖上，并允许乙醇干燥。 </li><li>打开管并转移5-10无菌Mosconas溶液中到一个新的50ml锥形管中。 </li><li>转移胶原水凝胶包含酶溶液的锥形管中。确保该水凝胶完全覆盖该溶液中。留在冰箱摇床管在4℃下30分钟。 </li><li>吸出Mosconas解决方案，并重复步骤7.2.5两次。 </li><li>保存在4℃。 </li></ol></li></ol>

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Today. 16, 496-504 (2013).</li><li>Billiet, T., Vandenhaute, M., Schelfhout, J., Van Vlierberghe, S., Dubruel, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+review+of+trends+and+limitations+in+hydrogel-rapid+prototyping+for+tissue+engineering.">A review of trends and limitations in hydrogel-rapid prototyping for tissue engineering.</a> Biomaterials. 33, 6020-6041 (2012).</li><li>Yost, M. J., 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=A+novel+tubular+scaffold+for+cardiovascular+tissue+engineering.">A novel tubular scaffold for cardiovascular tissue engineering.</a> Tissue Eng. 10, 273-284 (2004).</li><li>Habeeb, A. J., Hiramoto, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reaction+of+proteins+with+glutaraldehyde.">Reaction of proteins with glutaraldehyde.</a> Arch Biochem Biophys. 126, 16-26 (1968).</li><li>Tanford, C., Buzzell, J. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Viscosity+of+Aqueous+Solutions+of+Bovine+Serum+Albumin+between+pH+4.3+and+10.5.">The Viscosity of Aqueous Solutions of Bovine Serum Albumin between pH 4.3 and 10.5.</a> J. Phys. Chem. 60, 225-231 (1956).</li><li>Yadav, S., Shire, S. J., Kalonia, D. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Viscosity+analysis+of+high+concentration+bovine+serum+albumin+aqueous+solutions.">Viscosity analysis of high concentration bovine serum albumin aqueous solutions.</a> Pharm Res. 28, 1973-1983 (2011).</li><li>Tobitani, A., Ross-Murphy, S. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+intrinsic+viscosity+of+polyelectrolytes+revisited.">The intrinsic viscosity of polyelectrolytes revisited.</a> Polym. Int. 44, 338-347 (1997).</li><li>Arakawa, T., Timasheff, S. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Theory+of+protein+solubility.">Theory of protein solubility.</a> Methods Enzymol. 114, 49-77 (1985).</li><li>Migneault, I., Dartiguenave, C., Bertrand, M. J., Waldron, K. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Glutaraldehyde:+behavior+in+aqueous+solution,+reaction+with+proteins,+and+application+to+enzyme+crosslinking.">Glutaraldehyde: behavior in aqueous solution, reaction with proteins, and application to enzyme crosslinking.</a> Biotechniques. 37, 790-796 (2004).</li><li>Burmeister, J. J., 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=Glutaraldehyde+cross-linked+glutamate+oxidase+coated+microelectrode+arrays:+selectivity+and+resting+levels+of+glutamate+in+the+CNS.">Glutaraldehyde cross-linked glutamate oxidase coated microelectrode arrays: selectivity and resting levels of glutamate in the CNS.</a> ACS Chem Neurosci. 4, 721-728 (2013).</li><li>Chatterji, P. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gelatin+with+hydrophilic/hydrophobic+grafts+and+glutaraldehyde+crosslinks.">Gelatin with hydrophilic/hydrophobic grafts and glutaraldehyde crosslinks.</a> J. Appl. Polym. Sci. 37, 2203-2212 (1989).</li><li>Freije, J. R., 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=Chemically+modified,+immobilized+trypsin+reactor+with+improved+digestion+efficiency.">Chemically modified, immobilized trypsin reactor with improved digestion efficiency.</a> J Proteome Res. 4, 1805-1813 (2005).</li><li>Cunha-Filho, M. S., Alvarez-Lorenzo, C., Martinez-Pacheco, R., Landin, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Temperature-sensitive+gels+for+intratumoral+delivery+of+beta-lapachone:+effect+of+cyclodextrins+and+ethanol.">Temperature-sensitive gels for intratumoral delivery of beta-lapachone: effect of cyclodextrins and ethanol.</a> ScientificWorldJournal. 2012, 126723 (2012).</li><li>Basak, R., Bandyopadhyay, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Encapsulation+of+hydrophobic+drugs+in+Pluronic+F127+micelles:+effects+of+drug+hydrophobicity,+solution+temperature,+and+pH.">Encapsulation of hydrophobic drugs in Pluronic F127 micelles: effects of drug hydrophobicity, solution temperature, and pH.</a> Langmuir. 29, 4350-4356 (2013).</li></ol>

作者什么都没有透露。

生物制造是在生物学和工程学原理合并产生模仿自然组织复杂的材料高度多学科领域。为了达到这个目的，有必要开发使用从体内组织收集到的信息，并将其转换成一个在体外的支架技术。以这种方式，平台可改造成非常类似于体内组织的建筑，功能，和机械性能。最佳的支架材料应具有一定的性质，例如是生物相容的，模仿的感兴趣的组织的机械性能，能够受控降解的，能?...

在组织工程领域，制作组织支架的能力是至关重要的。合适的组织支架具有三维结构，是由生物相容的材料制成，并在体内组织架构模拟物，以促进细胞和组织的生长和重建。该支架必须允许营养物质的运输和清除废物1-4。一种在生产这些支架的主要障碍是概括特定几何特征成生物相容的材料的能力。几个生物制造技术已经报道，以控制这些支架的几何特征，实施例是静电5-8，溶剂浇铸9，立体光刻10，和3D印刷11，等等。这些技术达不到在提供相对容易的可控内部和外部的建筑特色转移，是昂贵的，由它们的分辨率和印刷性能（限<em&gt;例如，喷嘴计，材料限制），或需要制造后技术，这需要的时间，以产生可行的支架12长的时间。 在许多商业制造系统，内部空隙，通道和特征的创建是用砂或其他合适的可移动或牺牲材料来实现。的金属或塑料部件围绕砂模形成，并且一旦它被固化时，砂被去除。在大致相同的方式，下一代生物材料的所需要的生物沙等效。因此，波塞橡胶被开发作为用于生物沙的替代物。 BSA的橡胶是由具有戊二醛交联的牛血清白蛋白的一个新制定的材料。最终的目标是具体的建筑特色重建成可生物降解的胶原支架。维持二维保真度与原组织的模具牺牲biorubber的特性进行说明。 <p cl屁股="jove_content"&gt; BSA和戊二醛浓度的几种组合进行使用各种溶剂进行测试。该物质经BSA和戊二醛之间的反应产生。 BSA的橡胶可以是注入组织模具的复杂的几何形状的反应。交联的BSA的胰蛋白酶不稳定，并通过在温和的pH和温度条件下的酶容易地消化。相反，完整的I型胶原蛋白是胰蛋白酶消化非常有抗性。这些特征被资本以选择性地移除的BSA橡胶留下胶原后面。目前的工作包括确定获得不稳定的模具，可以到生物相容支架提供特定的建筑特色所需要的理想的参数。进行了评价，该具体特征包括混合性，酶消化，承载，和被注入阴模的反应能力。 30％BSA和3％戊二醛的组合满足这些要求。这个协议提供了necess元指导创建这些三维支架。所述原型包括表示与一个流入和直径分别为4-和3毫米，二流出通道的支链结构的胶原蛋白支架的。该技术具有模仿感兴趣的组织的宏观和微观环境的潜力。这种技术提供了一个可行的技术，以在以高的保真度，其可被调谐以模仿体内组织的弹性和感兴趣的组织的其他特性的相对容易且及时物质递送的特定几何启发可生物降解的材料。

<table border="0" cellpadding="0" cellspacing="0" width="770">
	<tbody>
		<tr height="20">
			<td height="20" style="height:20px;width:281px;">Collagen type I</td>
			<td style="width:156px;"></td>
			<td style="width:116px;"></td>
			<td style="width:217px;">Collagen extracted from calf hide</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Hydrocloric Acid (HCl)</td>
			<td>Sigma-Aldrich</td>
			<td>7647-01-0</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Phosphate Buffer Solution (PBS Tablets)</td>
			<td>MP Biomedical</td>
			<td>U5378</td>
			<td>1 tablet per 100 mL makes 1XPBS</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Albumium from bovine serum (BSA)</td>
			<td>Sigma-Aldrich</td>
			<td>A9647</td>
			<td></td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;">Glutaraldehyde</td>
			<td>Sigma -Aldrich</td>
			<td>G5882</td>
			<td>Toxic</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Lard</td>
			<td>Fields</td>
			<td>3090</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Stainless Steel Molds</td>
			<td></td>
			<td></td>
			<td>Milled using Microlution Machine</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Air Brush Kit</td>
			<td>Central Pneumatic</td>
			<td>47791</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Mixing Tip for double syringe</td>
			<td>Medmix</td>
			<td>ML2.5-16-LLM</td>
			<td>Mixer, DN2,5X16, 4:1 brown, med</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Small O ring for double syringe</td>
			<td>Medmix</td>
			<td>PPB-X05-04-02SM</td>
			<td>Piston B, 5mL, 4:1, PE natural</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Double Syringe cap&#160;</td>
			<td>Medmix</td>
			<td>VLX002-SM</td>
			<td>Cap, 4:1/10:1, PE brown, med</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Big O ring for double syringe</td>
			<td>Medmix</td>
			<td>PPA-X05-04-02SM</td>
			<td>Piston A, 5 mL, 4:1</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Double Syringe&#160;</td>
			<td>Medmix</td>
			<td>SDL X05-04-50M</td>
			<td>Double syringe, 5 mL, 4:1</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Double Syringe Dispenser</td>
			<td>Medmix</td>
			<td>DL05-0400M</td>
			<td>Dispenser, 5 mL, 4:1, med , plain</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Laminim</td>
			<td></td>
			<td></td>
			<td>3.6 mg/mL- extracted USC lab</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">20 mL Syringe Luer Lock Tip</td>
			<td>BD</td>
			<td>302830</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Luer Lock Caps</td>
			<td>Fisher</td>
			<td>JGTCBLLX</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">HEPES</td>
			<td>Sigma -Aldrich</td>
			<td>H4034</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Gibco Minimum Essential Media 10X (MEM)</td>
			<td>&#160;Life Technologies</td>
			<td>1143-030</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Trypsin</td>
			<td>Life Technologies</td>
			<td>27250-018</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">UV Crosslinker&#160;</td>
			<td>Spectroline UV</td>
			<td>XLE1000</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Sodium Cloride (NaCl)</td>
			<td>Fisher</td>
			<td>S271-10</td>
			<td>To prepare Mosconas</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Potassium chloride (KCl)</td>
			<td>Sigma -Aldrich</td>
			<td>P5405-250</td>
			<td>To prepare Mosconas</td>
		</tr>
		<tr height="24">
			<td height="24" style="height:24px;">Sodium Bicarbonate (NaHCO3)</td>
			<td>Fisher</td>
			<td>BP328-500</td>
			<td>To prepare Mosconas</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Glucose</td>
			<td>Sigma -Aldrich</td>
			<td>G-8270</td>
			<td>To prepare Mosconas</td>
		</tr>
		<tr height="24">
			<td height="24" style="height:24px;">Sodium Phosphate didasic (NaH2PO4)</td>
			<td>Sigma-Aldrich</td>
			<td>S-7907</td>
			<td>To prepare Mosconas</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Sterile Filter for syringes</td>
			<td>Corning</td>
			<td>431224</td>
			<td></td>
		</tr>
	</tbody>
</table>

three-dimensional biomimetic technology: novel biorubber creates defined micro- and macro-scale architectures in collagen hydrogels

组织支架起到组织再生过程中的关键作用。理想的脚手架必须满足几个条件，如适当有组成，有针对性的模量，以及明确的建筑特色。该概括体内组织的内在结构的生物材料可用于研究疾病，以及便于丢失和畸形软组织的再生是至关重要的。一种新型的生物制造技术的开发，结合​​了先进的成像，三维（3D）打印，和选择性酶活性的国家创造了新一代​​生物材料的研究和临床应用。开发材料，牛血清白蛋白橡胶，是注入一个维护特定几何特征的模具的反应。这种牺牲材料允许建筑特色的充分转移到天然支架材料。所述原型包括一个三维胶原蛋白支架的带4和3mm渠道再版ESENT支架构。本文强调的自然结构的产生使用这种生物制造技术。这个协议利用计算机辅助软件（CAD）来制造固体模具，这将是用BSA橡胶接着橡胶的酶消化注入反应，而使支架材料内的建筑特色。

的结果表明，该生物制造技术是在产生三维支架，可以模仿体内组织中所看到的空间排列高效。建筑特色是用于组织工程应用的重要参数，打在组织的体内细胞相互作用和功能的关键作用。 BSA的橡胶的一致​​性和混合能力是在生产的BSA橡胶是均匀的，并能保持其预定形状的重要参数。蛋白质的溶解度是通过分?...

Watch this Scientific Journal Video about Three-dimensional Biomimetic Technology: Novel Biorubber Creates Defined Micro- and Macro-scale Architectures in Collagen Hydrogels at JoVE.com

Three-dimensional Biomimetic Technology: Novel Biorubber Creates Defined Micro- and Macro-scale Architectures in Collagen Hydrogels

An innovative biofabrication technique was developed to engineer three-dimensional constructs that resemble the architectural features, components, and mechanical properties of in vivo tissue. This technique features a newly developed sacrificial material, BSA rubber, which transfers detailed spatial features, reproducing the in vivo architectures of a wide variety of tissues.

三维仿生技术:新型Biorubber创建自定义微观和宏观尺度架构的胶原凝胶

Tissue scaffolds play a crucial role in the tissue regeneration process. The ideal scaffold must fulfill several requirements such as having proper ...

three-dimensional-biomimetic-technology-novel-biorubber-creates

Research

JoVE Journal

Bioengineering

9.1K 次观看.  Medical University of South Carolina. An innovative biofabrication technique was developed to engineer three-dimensional constructs that resemble the architectural features, components, and mechanical properties of in vivo tissue. This technique features a newly developed sacrificial material, BSA rubber, which transfers detailed spatial features, reproducing the in vivo architectures of a wide variety of tissues.

视频: Three-dimensional Biomimetic Technology: Novel Biorubber Creates Defined Micro- and Macro-scale Architectures in Collagen Hydrogels

Fabrication of Micro-tissues using Modules of Collagen Gel Containing Cells

This protocol describes the fabrication of a type of micro-tissues called modules.  The module approach generates uniform, scalable and vascularized tissues.  The modules can be made of collagen as well as other gelable or crosslinkable materials.  They are approximately 2 mm in length and 0.7 mm in diameter upon fabrication but shrink in size with embedded cells or when the modules are coated with endothelial cells.  The modules individually are small enough that the embedded cells are within the diffusion limit of oxygen and other nutrients but modules can be packed together to form larger tissues that are perfusable.  These tissues are modular in construction because different cell types can be embedded in or coated on the modules before they are packed together to form complex tissues.  There are three main steps to making the modules: (1) neutralizing the collagen and embedding cells in it, (2) gelling the collagen in the tube and cutting the modules and (3) coating the modules with endothelial cells.

Creation of micro-tissues using cylindrical collagen gels, called modules, that contain embedded cells and which surface is coated with endothelial cells.

微组织使用胶原蛋白的模块的制备凝胶含有细胞

This protocol describes the fabrication of a type of micro-tissues called modules.  The module approach generates uniform, scalable and vascularized ...

科研

生物工程

Three-dimensional Optical-resolution Photoacoustic Microscopy

Optical microscopy, providing valuable insights at the cellular and organelle levels, has been widely recognized as an enabling biomedical technology. As the mainstays of in vivo three-dimensional (3-D) optical microscopy, single-/multi-photon fluorescence microscopy and optical coherence tomography (OCT) have demonstrated their extraordinary sensitivities to fluorescence and optical scattering contrasts, respectively. However, the optical absorption contrast of biological tissues, which encodes essential physiological/pathological information, has not yet been assessable. 
The emergence of biomedical photoacoustics has led to a new branch of optical microscopy optical-resolution photoacoustic microscopy (OR-PAM)1, where the optical irradiation is focused to the diffraction limit to achieve cellular1 or even subcellular2 level lateral resolution. As a valuable complement to existing optical microscopy technologies, OR-PAM brings in at least two novelties. First and most importantly, OR-PAM detects optical absorption contrasts with extraordinary sensitivity (i.e., 100%). Combining OR-PAM with fluorescence microscopy3 or with optical-scattering-based OCT4 (or with both) provides comprehensive optical properties of biological tissues. Second, OR-PAM encodes optical absorption into acoustic waves, in contrast to the pure optical processes in fluorescence microscopy and OCT, and provides background-free detection. The acoustic detection in OR-PAM mitigates the impacts of optical scattering on signal degradation and naturally eliminates possible interferences (i.e., crosstalks) between excitation and detection, which is a common problem in fluorescence microscopy due to the overlap between the excitation and fluorescence spectra. 
Unique for optical absorption imaging, OR-PAM has demonstrated broad biomedical applications since its invention, including, but not limited to, neurology5, 6, ophthalmology7, 8, vascular biology9, and dermatology10. In this video, we teach the system configuration and alignment of OR-PAM as well as the experimental procedures for in vivo functional microvascular imaging.

Optical-resolution photoacoustic microscopy (OR-PAM) is an emerging technology capable of imaging optical absorption contrasts in vivo with cellular resolution and sensitivity. Here, we provide a visualized instruction on the experimental protocols of OR-PAM, including system configuration, system alignment, typical in vivo experimental procedures, and functional imaging schemes.

三维光学分辨率的光声显微镜

Optical microscopy, providing valuable insights at the cellular and organelle levels, has been widely recognized as an enabling biomedical technology. As ...

Alginate Hydrogels for Three-Dimensional Organ Culture of Ovaries and Oviducts

Ovarian cancer is the fifth leading cause of cancer deaths in women and has a 63% mortality rate in the United States1. The cell type of origin for ovarian cancers is still in question and might be either the ovarian surface epithelium (OSE) or the distal epithelium of the fallopian tube fimbriae2,3. Culturing the normal cells as a primary culture in vitro will enable scientists to model specific changes that might lead to ovarian cancer in the distinct epithelium, thereby definitively determining the cell type of origin. This will allow development of more accurate biomarkers, animal models with tissue-specific gene changes, and better prevention strategies targeted to this disease.
Maintaining normal cells in alginate hydrogels promotes short term in vitro culture of cells in their three-dimensional context and permits introduction of plasmid DNA, siRNA, and small molecules. By culturing organs in pieces that are derived from strategic cuts using a scalpel, several cultures from a single organ can be generated, increasing the number of experiments from a single animal. These cuts model aspects of ovulation leading to proliferation of the OSE, which is associated with ovarian cancer formation. Cell types such as the OSE that do not grow well on plastic surfaces can be cultured using this method and facilitate investigation into normal cellular processes or the earliest events in cancer formation4.
Alginate hydrogels can be used to support the growth of many types of tissues5. Alginate is a linear polysaccharide composed of repeating units of &beta;-D-mannuronic acid and &alpha;-L-guluronic acid that can be crosslinked with calcium ions, resulting in a gentle gelling action that does not damage tissues6,7. Like other three-dimensional cell culture matrices such as Matrigel, alginate provides mechanical support for tissues; however, proteins are not reactive with the alginate matrix, and therefore alginate functions as a synthetic extracellular matrix that does not initiate cell signaling5. The alginate hydrogel floats in standard cell culture medium and supports the architecture of the tissue growth in vitro.
A method is presented for the preparation, separation, and embedding of ovarian and oviductal organ pieces into alginate hydrogels, which can be maintained in culture for up to two weeks. The enzymatic release of cells for analysis of proteins and RNA samples from the organ culture is also described. Finally, the growth of primary cell types is possible without genetic immortalization from mice and permits investigators to use knockout and transgenic mice.

Culture of normal cells in their three-dimensional context represents an alternative method to study early events required for cellular transformation and tumorigenesis. This method is used to grow normal ovarian and oviductal cells to study early events in ovarian cancer formation.

卵巢和输卵管的三维器官培养的海藻酸钙凝胶

Ovarian cancer is the fifth leading cause of cancer deaths in women and has a 63% mortality rate in the United States1. The cell type of origin for ...

Planar and Three-Dimensional Printing of Conductive Inks

Printed electronics rely on low-cost, large-area fabrication routes to create flexible or multidimensional electronic, optoelectronic, and biomedical devices1-3. In this paper, we focus on one- (1D), two- (2D), and three-dimensional (3D) printing of conductive metallic inks in the form of flexible, stretchable, and spanning microelectrodes.
Direct-write assembly4,5 is a 1-to-3D printing technique that enables the fabrication of features ranging from simple lines to complex structures by the deposition of concentrated inks through fine nozzles (~0.1 - 250 &mu;m). This printing method consists of a computer-controlled 3-axis translation stage, an ink reservoir and nozzle, and 10x telescopic lens for visualization. Unlike inkjet printing, a droplet-based process, direct-write assembly involves the extrusion of ink filaments either in- or out-of-plane. The printed filaments typically conform to the nozzle size. Hence, microscale features (&lt; 1 &mu;m) can be patterned and assembled into larger arrays and multidimensional architectures.
In this paper, we first synthesize a highly concentrated silver nanoparticle ink for planar and 3D printing via direct-write assembly. Next, a standard protocol for printing microelectrodes in multidimensional motifs is demonstrated. Finally, applications of printed microelectrodes for electrically small antennas, solar cells, and light-emitting diodes are highlighted.

Planar and three-dimensional printing of conductive metallic inks is described. Our approach provides new avenues for fabricating printed electronic, optoelectronic, and biomedical devices in unusual layouts at the microscale.

平面和立体印刷的导电油墨

Printed electronics rely on low-cost, large-area fabrication routes to create flexible or multidimensional electronic, optoelectronic, and biomedical ...

Cell Patterning on Photolithographically Defined 
Parylene-C: SiO2 Substrates

Cell patterning platforms support broad research goals, such as construction of predefined in vitro neuronal networks and the exploration of certain central aspects of cellular physiology. To easily combine cell patterning with Multi-Electrode Arrays (MEAs) and silicon-based &#8216;lab on a chip&#8217; technologies, a microfabrication-compatible protocol is required. We describe a method that utilizes deposition of the polymer parylene-C on SiO2&#160;wafers. Photolithography enables accurate and reliable patterning of parylene-C at micron-level resolution. Subsequent activation by immersion in fetal bovine serum (or another specific activation solution) results in a substrate in which cultured cells adhere to, or are repulsed by, parylene or SiO2 regions respectively. This technique has allowed patterning of a broad range of cell types (including primary murine hippocampal cells, HEK 293 cell line, human neuron-like teratocarcinoma cell line, primary murine cerebellar granule cells, and primary human glioma-derived stem-like cells). Interestingly, however, the platform is not universal; reflecting the importance of cell-specific adhesion molecules. This cell patterning process is cost effective, reliable, and importantly can be incorporated into standard microfabrication (chip manufacturing) protocols, paving the way for integration of microelectronic technology.

Cell Patterning on Photolithographically Defined 
Parylene-C: SiO2 Substrates

This protocol describes a microfabrication-compatible method for cell patterning on SiO2. A predefined parylene-C design is photolithographically printed on SiO2 wafers. Following incubation with serum (or other activation solution) cells adhere specifically to (and grow according to the conformity of) underlying parylene-C, whilst being repulsed by SiO2 regions.

在光刻技术定义的聚对二甲苯-C细胞图案:二氧化硅<sub&gt; 2</sub&gt;基板

Cell patterning platforms support broad research goals, such as construction of predefined in vitro neuronal networks and the exploration of certain ...

Human Cartilage Tissue Fabrication Using Three-dimensional Inkjet Printing Technology

Bioprinting, which is based on thermal inkjet printing, is one of the most attractive enabling technologies in the field of tissue engineering and regenerative medicine. With digital control&#160;cells, scaffolds, and growth factors can be precisely deposited to the desired two-dimensional (2D) and three-dimensional (3D) locations rapidly. Therefore, this technology is an ideal approach to fabricate tissues mimicking their native anatomic structures. In order to engineer cartilage with native zonal organization, extracellular matrix composition (ECM), and mechanical properties, we developed a bioprinting platform using a commercial inkjet printer with simultaneous photopolymerization capable for 3D cartilage tissue engineering. Human chondrocytes suspended in poly(ethylene glycol) diacrylate (PEGDA) were printed for 3D neocartilage construction via layer-by-layer assembly. The printed cells were fixed at their original deposited positions, supported by the surrounding scaffold in simultaneous photopolymerization. The mechanical properties of the printed tissue were similar to the native cartilage. Compared to conventional tissue fabrication, which requires longer UV exposure, the viability of the printed cells with simultaneous photopolymerization was significantly higher. Printed neocartilage demonstrated excellent glycosaminoglycan (GAG) and collagen type II production, which was consistent with gene expression. Therefore, this platform is ideal for accurate cell distribution and arrangement for anatomic tissue engineering.

The methods described in this paper show how to convert a commercial inkjet printer into a bioprinter with simultaneous UV polymerization. The printer is capable of constructing 3D tissue structure with cells and biomaterials. The study demonstrated here constructed a 3D neocartilage.

人体软骨组织制作采用三维喷墨打印技术

Bioprinting, which is based on thermal inkjet printing, is one of the most attractive enabling technologies in the field of tissue engineering and ...

Analysis of Cell Migration within a Three-dimensional Collagen Matrix

The ability to migrate is a hallmark of various cell types and plays a crucial role in several physiological processes, including&#160;embryonic development, wound healing, and immune responses. However, cell migration is also a key mechanism in cancer enabling these cancer cells to detach from the primary tumor to start metastatic spreading. Within the past years various cell migration assays have been developed to analyze the migratory behavior of different cell types. Because the locomotory behavior of cells markedly differs between a two-dimensional (2D) and three-dimensional (3D) environment it can be assumed that the analysis of the migration of cells that are embedded within a 3D environment would yield in more significant cell migration data. The advantage of the described 3D collagen matrix migration assay is that cells are embedded within a physiological 3D network of collagen fibers representing the major component of the extracellular matrix. Due to time-lapse video microscopy real cell migration is measured allowing the determination of several migration parameters as well as their alterations in response to pro-migratory factors or inhibitors. Various cell types could be analyzed using this technique, including lymphocytes/leukocytes, stem cells, and tumor cells. Likewise, also cell clusters or spheroids could be embedded within the collagen matrix concomitant with analysis of the emigration of single cells from the cell cluster/ spheroid into the collagen lattice. We conclude that the 3D collagen matrix migration assay is a versatile method to analyze the migration of cells within a physiological-like 3D environment.

Cell migration is a biological phenomenon that is involved in a plethora of physiological, such as wound healing and immune responses, and pathophysiological processes, like cancer. The 3D-collagen matrix migration assay is a versatile tool to analyze the migratory properties of different cell types within in a 3D physiological-like environment.

在一个三维胶原蛋白矩阵分析细胞迁移

The ability to migrate is a hallmark of various cell types and plays a crucial role in several physiological processes, including&#160;embryonic ...

Generation of a Three-dimensional Full Thickness Skin Equivalent and Automated Wounding

In vitro models are a cost effective and ethical alternative to study cutaneous wound healing processes. Moreover, by using human cells, these models reflect the human wound situation better than animal models. Although two-dimensional models are widely used to investigate processes such as cellular migration and proliferation, models that are more complex are required to gain a deeper knowledge about wound healing. Besides a suitable model system, the generation of precise and reproducible wounds is crucial to ensure comparable results between different test runs. In this study, the generation of a three-dimensional full thickness skin equivalent to study wound healing is shown. The dermal part of the models is comprised of human dermal fibroblast embedded in a rat-tail collagen type I hydrogel. Following the inoculation with human epidermal keratinocytes and consequent culture at the air-liquid interface, a multilayered epidermis is formed on top of the models. To study the wound healing process, we additionally developed an automated wounding device, which generates standardized wounds in a sterile atmosphere.

The goal of this protocol is to build up a three-dimensional full thickness skin equivalent, which resembles natural skin. With a specifically constructed automated wounding device, precise and reproducible wounds can be generated under maintenance of sterility.

三维全层皮肤的生成等效和自动伤人

In vitro models are a cost effective and ethical alternative to study cutaneous wound healing processes. Moreover, by using human cells, these models ...

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.

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 ...

Ultrathin Porated Elastic Hydrogels As a Biomimetic Basement Membrane for Dual Cell Culture

The basement membrane is a critical component of cellular bilayers that can vary in stiffness, composition, architecture, and porosity. In vitro studies of endothelial-epithelial bilayers have traditionally relied on permeable support models that enable bilayer culture, but permeable supports are limited in their ability to replicate the diversity of human basement membranes. In contrast, hydrogel models that require chemical synthesis are highly tunable and allow for modifications of both the material stiffness and the biochemical composition via incorporation of biomimetic peptides or proteins. However, traditional hydrogel models are limited in functionality because they lack pores for cell-cell contacts and functional in vitro migration studies. Additionally, due to the thickness of traditional hydrogels, incorporation of pores that span the entire thickness of hydrogels has been challenging. In the present study, we use poly-(ethylene-glycol) (PEG) hydrogels and a novel zinc oxide templating method to address the previous shortcomings of biomimetic hydrogels. As a result, we present an ultrathin, basement membrane-like hydrogel that permits the culture of confluent cellular bilayers on a customizable scaffold with variable pore architectures, mechanical properties, and biochemical composition.

Current bilayer culture models do not allow for functional in vitro studies that mimic in vivo microenvironments. Using polyethylene glycol and a zinc oxide templating method, this protocol describes the development of an ultrathin biomimetic basement membrane with tunable stiffness, porosity, and biochemical composition that closely mimics in vivo extracellular matrices.

超薄 Porated 弹性水凝胶作为双细胞培养的仿生基底膜

The basement membrane is a critical component of cellular bilayers that can vary in stiffness, composition, architecture, and porosity. In vitro studies ...