Microfluidic direct writer with integrated declogging mechanism for fabricating cell-laden hydrogel constructs
Microfluidic direct writer with integrated declogging mechanism for fabricating cell-laden hydrogel constructs
复制标题
DOI：
10.1007/s10544-014-9842-8
复制
发表时间：
2014-06-01
影响因子：
2.8
通讯作者：
Juncker, David
中科院分区：
文献类型：
--
作者：
Ghorbanian, Setareh;Qasaimeh, Mohammad A.;Juncker, David
3D水凝胶支架的细胞分布和营养供应至关重要，必须模拟体内细胞环境，但传统的制造方法难以控制。在这里，我们提出了一种微流体直接写入器（MFDW）来构建具有允许介质交换的开口的3D细胞负载水凝胶结构。MFDW包括一个单片微流控头，它可以输送含有细胞的海藻酸钠和氯化钙溶液的同轴流，形成水凝胶纤维。通过调节体积流量的比例来控制纤维直径。MFDW头安装在一个电动平台上，该平台自动控制，并以与纤维制造速度同步的速度移动。对书写液的封头几何形状、流速和粘度进行了优化，以防止卷边和胀形的发生。为了持续使用，需要一个高度可靠的工艺，这是通过集成一个排水管道来实现的，该管道提供溶剂来溶解堵塞凝胶。MFDW用于逐层制备具有封装单元的简单三维结构。通过交替提供两种不同的海藻酸盐凝胶溶液，演示了具有不同纤维的3D结构的组装。MFDW头可以快速，轻松地构建，并将允许组织工程的3D结构与多种水凝胶和细胞类型制造。
Cell distribution and nutrient supply in 3D cell-laden hydrogel scaffolds are critical and should mimic the in vivo cellular environment, but been difficult to control with conventional fabrication methods. Here, we present a microfluidic direct writer (MFDW) to construct 3D cell-laden hydrogel structures with openings permitting media exchange. The MFDW comprises a monolithic microfluidic head, which delivers coaxial streams of cell-laden sodium alginate and calcium chloride solutions to form hydrogel fibers. Fiber diameter is controlled by adjusting the ratio of the volumetric flow rates. The MFDW head is mounted on a motorized stage, which is automatically controlled and moves at a speed synchronized with the speed of fiber fabrication. Head geometry, flow rates, and viscosity of the writing solutions were optimized to prevent the occurrence of curling and bulging. For continuous use, a highly reliable process is needed, which was accomplished with the integration of a declogging conduit supplying a solvent to dissolve the clogging gel. The MFDW was used for layer-by-layer fabrication of simple 3D structures with encapsulated cells. Assembly of 3D structures with distinct fibers is demonstrated by alternatively delivering two different alginate gel solutions. The MFDW head can be built rapidly and easily, and will allow 3D constructs for tissue engineering to be fabricated with multiple hydrogels and cell types.