Fu Guanglei, Zhou Wan, Li XiuJun
Department of Chemistry and Biochemistry, University of Texas at El Paso, 500 West University Ave, El Paso, Texas 79968, USA.
Lab Chip. 2020 Jun 16;20(12):2218-2227. doi: 10.1039/d0lc00317d.
The requirement of on-demand microfluidic pumps and instrument-free readout methods remains a major challenge for the development of microfluidics. Herein, a new type of microfluidic platform, an on-demand photothermal microfluidic pumping platform, has been developed using an on-chip nanomaterial-mediated photothermal effect as novel and remotely tunable microfluidic driving force. The photothermal microfluidic pumping performance can be adjusted remotely by tuning the irradiation parameters, without changing on-chip parameters or replacing enzymes or other reagents. In contrast to graphene oxide, Prussian blue nanoparticles with higher photothermal conversion efficiency were used as the model photothermal agent to demonstrate the proof of concept. The on-chip pumping distance is linearly correlated with both the irradiation time and the nanomaterial concentration. The applications of photothermal microfluidic pumping have been demonstrated in multiplexed on-chip transport of substances, such as gold nanoparticles, and visual quantitative bar-chart detection of cancer biomarkers without using specialized instruments. Upon contact-free irradiation using a laser pointer, a strong on-chip nanomaterial-mediated photothermal effect can serve as a robust and remotely tunable microfluidic pump in a PMMA/PDMS hybrid bar-chart chip to drive ink bars in a visual quantitative readout fashion. This is the first report on a photothermal microfluidic pumping platform, which has great potential for various microfluidic applications.
对按需微流泵和无需仪器读出方法的需求仍然是微流控技术发展的主要挑战。在此，一种新型微流控平台——按需光热微流泵平台已被开发出来，它利用芯片上纳米材料介导的光热效应作为新型且可远程调节的微流动力。通过调整照射参数可远程调节光热微流泵的性能，而无需改变芯片上的参数或更换酶或其他试剂。与氧化石墨烯不同，具有更高光热转换效率的普鲁士蓝纳米颗粒被用作模型光热剂来证明概念验证。芯片上的泵送距离与照射时间和纳米材料浓度均呈线性相关。光热微流泵的应用已在诸如金纳米颗粒等物质的多重芯片上运输以及无需使用专门仪器的癌症生物标志物的可视化定量条形图检测中得到了证明。使用激光笔进行非接触式照射时，芯片上强大的纳米材料介导的光热效应可在聚甲基丙烯酸甲酯/聚二甲基硅氧烷混合条形图芯片中充当强大且可远程调节的微流泵，以可视化定量读出的方式驱动墨条。这是关于光热微流泵平台的首次报道，其在各种微流控应用中具有巨大潜力。
