Zhang Tao, Meng Jiyu, Li Shanshan, Yu Chengzhuang, Li Junwei, Wei Chunyang, Dai Shijie
Hebei Key Laboratory of Robotic Sensing and Human-robot interactions, School of Mechanical Engineering, Hebei University of Technology, Tianjin 300132, China.
National Key Laboratory of Reliability and Electrical Equipment, Hebei University of Technology, Tianjin 300130, China.
Micromachines (Basel). 2020 Mar 10;11(3):284. doi: 10.3390/mi11030284.
Microfluidic chips-in which chemical or biological fluid samples are mixed into linear or nonlinear concentration distribution profiles-have generated enormous enthusiasm of their ability to develop patterns for drug release and their potential toxicology applications. These microfluidic devices have untapped potential for varying concentration patterns by the use of one single device or by easy-to-operate procedures. To address this challenge, we developed a soft-lithography-fabricated microfluidic platform that enabled one single device to be used as a concentration maker, which could generate linear, bell-type, or even S-type concentration profiles by tuning the feed flow rate ratios of each independent inlet. Here, we present an FFRR (feed flow rate ratio) adjustment approach to generate tens of types of concentration gradient profiles with one single device. To demonstrate the advantages of this approach, we used a Christmas-tree-like microfluidic chip as the demo. Its performance was analyzed using numerical simulation models and experimental investigations, and it showed an excellent time response (~10 s). With on-demand flow rate ratios, the FFRR microfluidic device could be used for many lab-on-a-chip applications where flexible concentration profiles are required for analysis.
微流控芯片可将化学或生物流体样本混合成线性或非线性浓度分布曲线，其在开发药物释放模式及潜在毒理学应用方面的能力引发了极大的热情。这些微流控设备通过使用单个设备或易于操作的程序来改变浓度模式，具有尚未开发的潜力。为应对这一挑战，我们开发了一种通过软光刻制造的微流控平台，该平台能使单个设备用作浓度生成器，通过调整每个独立入口的进料流速比，可生成线性、钟形甚至S形浓度曲线。在此，我们提出一种进料流速比（FFRR）调整方法，用单个设备生成数十种浓度梯度曲线。为证明该方法的优势，我们使用了一个圣诞树状微流控芯片作为演示。通过数值模拟模型和实验研究对其性能进行了分析，结果显示其具有出色的时间响应（约10秒）。通过按需调整流速比，FFRR微流控设备可用于许多需要灵活浓度曲线进行分析的芯片实验室应用。
