Jiang Hongjie, Ochoa Manuel, Rahimi Rahim, Yu Wuyang, Ziaie Babak
School of Electrical and Computer Engineering, Purdue University West Lafayette IN 47907 USA
Birck Nanotechnology Center, Purdue University West Lafayette IN 47907 USA.
RSC Adv. 2019 Jun 21;9(34):19531-19538. doi: 10.1039/c9ra03448j. eCollection 2019 Jun 19.
In this work, we present a laser-based fabrication technique for direct patterning of micro-channels consisting of interconnected micro-cracks on soda-lime glass. Using a CO laser to deposit energy at a linear rate of 18.75 to 93.75 mJ mm, we were able to manipulate the micro-crack formation, while enabling rapid manufacturing and scalable production of cracked-glass microfluidic patterns on glass. At the higher end of the energy deposition rate (93.75 mJ mm), the laser fabricated microfluidic channels (1 mm wide and 20 mm long) had extremely fast wicking speeds (24.2 mm s, ×10 faster than filter paper) as a result of significant capillary action and laser-induced surface hydrophilization. At the lower end (18.75 mJ mm), 3-4 μm wide micro-cracked crevices resulted in an increased mesh/sieve density, hence, more efficiently filtering particle-laden liquid samples. The reproducibility tests revealed an averaged wicking speed of 10.6 ± 1.5 mm s measured over 21 samples fabricated under similar conditions, similar to that of filter paper (∼85%). The micro-cracked channels exhibited a stable shelf life of at least 82 days with a wicking speed within 10-13 mm s.
在这项工作中，我们提出了一种基于激光的制造技术，用于在钠钙玻璃上直接制作由相互连接的微裂纹组成的微通道图案。使用连续波（CO）激光以18.75至93.75 mJ/mm的线性速率沉积能量，我们能够控制微裂纹的形成，同时实现玻璃上裂纹玻璃微流控图案的快速制造和可扩展生产。在能量沉积速率的高端（93.75 mJ/mm），激光制造的微流控通道（宽1 mm，长20 mm）由于显著的毛细作用和激光诱导的表面亲水化，具有极快的芯吸速度（24.2 mm/s，比滤纸快10倍）。在低端（18.75 mJ/mm），3-4μm宽的微裂纹缝隙导致网孔/筛网密度增加，因此能够更有效地过滤含颗粒的液体样品。重复性测试显示，在类似条件下制造的21个样品上测得的平均芯吸速度为10.6±1.5 mm/s，与滤纸的芯吸速度相似（约85%）。微裂纹通道表现出至少82天的稳定保质期，芯吸速度在10-13 mm/s范围内。
