Cinvestav-Monterrey, 66600, Apodaca, Nuevo León, Mexico.
Lab Chip. 2018 Feb 13;18(4):662-669. doi: 10.1039/c7lc01337j.
In this article, we describe a microfluidic device with embedded valves and pumps made exclusively of layers of acrylic glass. Flat acrylic sheets are carved out with a micromilling machine and bonded together by solvent bonding. The working principle of the valves is based on a thin flexible membrane (≈100 μm) machined on one acrylic sheet and actuated with pneumatic pressure. A completely closed valve resists a pressure difference of ≈17 kPa (≈2.5 psi), and when open, it can sustain flow rates of up to 100 μL s. Pumping is achieved by combining two valves and a pumping chamber in series, which is also based on the bending of a thin acrylic membrane. The maximum flow rate obtained with this pumping mechanism is 20 μL min. Acrylic is a popular rigid thermoplastic because it is inexpensive, making it ideal for mass production of disposable devices, and also because it has demonstrated compatibility with different biochemical assays. The physical and optical properties it shares with other thermoplastics could lead to this material being implemented for similar valves and pumps. As a proof-of-concept of our technology, we implemented a controlled cell-staining assay in two parallel incubation chambers integrating four valves and one pump into one device. Our monolithic acrylic valves can enable the mass production of disposable microfluidic devices that require fluid control with pressure-actuated valves and aid in the automation of biochemical assays.
在本文中，我们描述了一种完全由亚克力玻璃层构成的、带有嵌入式阀门和泵的微流控装置。使用微铣床对扁平亚克力板进行雕刻，并通过溶剂键合将它们粘在一起。阀门的工作原理基于在一片亚克力板上加工的薄柔性膜（≈100μm），并通过气动压力驱动。完全关闭的阀门可抵抗约 17kPa（≈2.5psi）的压差，而当打开时，它可以承受高达 100μL/s 的流速。通过串联两个阀门和一个泵送腔来实现泵送，这也是基于薄亚克力膜的弯曲。通过这种泵送机制获得的最大流速为 20μL/min。亚克力是一种流行的刚性热塑性塑料，因为它价格低廉，非常适合一次性设备的大规模生产，并且还因为它已经证明与不同的生化分析兼容。它与其他热塑性塑料所共有的物理和光学特性可能会导致这种材料被用于类似的阀门和泵。作为我们技术的概念验证，我们在两个平行的孵育腔中实施了受控细胞染色测定，其中一个装置集成了四个阀门和一个泵。我们的整体式亚克力阀门可以实现需要压力驱动阀门进行流体控制的一次性微流控设备的大规模生产，并有助于生化分析的自动化。
