Schneider Philip J, Christie Liam B, Eadie Nicholas M, Siskar Tyler J, Sukhotskiy Viktor, Koh Domin, Wang Anyang, Oh Kwang W
SMALL (Sensors and Micro Actuators Learning Lab), Department of Electrical Engineering, University at Buffalo, The State University of New York (SUNY at Buffalo), Buffalo, NY 14260, USA.
Department of Mechanical Engineering, University at Buffalo, The State University of New York (SUNY at Buffalo), Buffalo, NY 14260, USA.
Micromachines (Basel). 2024 Feb 5;15(2):240. doi: 10.3390/mi15020240.
A wax-based contact printing method to create microfluidic devices is demonstrated. This printing technology demonstrates a new pathway to rapid, cost-effective device prototyping, eliminating the use of expensive micromachining equipment and chemicals. Derived from the traditional Ukrainian Easter egg painting technique called "pysanky" a series of microfluidic devices were created. Pysanky is the use of a heated wax stylus, known as a "kistka", to create micro-sized, intricate designs on the surface of an egg. The proposed technique involves the modification of an x-y-z actuation translation system with a wax extruder tip in junction with Polydimethysiloxane (PDMS) device fabrication techniques. Initial system optimization was performed considering design parameters such as extruder tip size, contact angle, write speed, substrate temperature, and wax temperature. Channels created ranged from 160 to 900 μm wide and 10 to 150 μm high based upon system operating parameters set by the user. To prove the capabilities of this technology, a series of microfluidic mixers were created via the wax technique as well as through traditional photolithography: a spiral mixer, a rainbow mixer, and a linear serial dilutor. A thermo-fluidic computational fluid dynamic (CFD) model was generated as a means of enabling rational tuning, critical to the optimization of systems in both normal and extreme conditions. A comparison between the computational and experimental models yielded a wax height of 57.98 μm and 57.30 μm, respectively, and cross-sectional areas of 11,568 μm and 12,951 μm, respectively, resulting in an error of 1.18% between the heights and 10.76% between the cross-sectional areas. The device's performance was then compared using both qualitative and quantitative measures, considering factors such as device performance, channel uniformity, repeatability, and resolution.
展示了一种基于蜡的接触式印刷方法来制造微流控设备。这种印刷技术为快速、经济高效的设备原型制作开辟了一条新途径，无需使用昂贵的微加工设备和化学品。借鉴了乌克兰传统的复活节彩蛋绘制技术“pysanky”，制作了一系列微流控设备。“pysanky”是使用一种加热的蜡笔，称为“kistka”，在鸡蛋表面绘制微小而复杂的图案。所提出的技术涉及对x - y - z驱动平移系统进行修改，使其与蜡挤出头相结合，并采用聚二甲基硅氧烷（PDMS）设备制造技术。考虑到挤出头尺寸、接触角、写入速度、基板温度和蜡温度等设计参数进行了初始系统优化。根据用户设置的系统操作参数，所创建的通道宽度范围为160至900μm，高度为10至150μm。为了证明该技术的能力，通过蜡技术以及传统光刻法制作了一系列微流控混合器：螺旋混合器、彩虹混合器和线性串行稀释器。生成了一个热流体计算流体动力学（CFD）模型，作为实现合理调谐的一种手段，这对于在正常和极端条件下优化系统至关重要。计算模型与实验模型的比较结果显示，蜡高度分别为57.98μm和57.30μm，横截面积分别为11,568μm²和12,951μm²，高度误差为1.18%，横截面积误差为10.76%。然后使用定性和定量指标对设备性能进行比较，考虑了设备性能、通道均匀性、可重复性和分辨率等因素。
