University of Maryland, Department of Chemistry and Biochemistry, College Park, Maryland, United States.
National Institute of Standards and Technology, Microsystems and Nanotechnology Division, Gaithersbu, United States.
J Biomed Opt. 2022 Jan;27(1). doi: 10.1117/1.JBO.27.1.017001.
Performance improvements in microfluidic systems depend on accurate measurement and fluid control on the micro- and nanoscales. New applications are continuously leading to lower volumetric flow rates.
We focus on improving an optofluidic system for measuring and calibrating microflows to the sub-nanoliter per minute range.
Measurements rely on an optofluidic system that delivers excitation light and records fluorescence in a precise interrogation region of a microfluidic channel. Exploiting a scaling relationship between the flow rate and fluorescence emission after photobleaching, the system enables real-time determination of flow rates.
Here, we demonstrate improved calibration of a flow controller to 1% uncertainty. Further, the resolution of the optofluidic flow meter improved to less than 1 nL / min with 5% uncertainty using a molecule with a 14-fold smaller diffusion coefficient than our previous report.
We demonstrate new capabilities in sub-nanoliter per minute flow control and measurement that are generalizable to cutting-edge light-material interaction and molecular diffusion for chemical and biomedical industries.
微流控系统的性能提升依赖于在微观和纳米尺度上进行准确的测量和流体控制。新的应用不断导致更低的体积流量。
我们专注于改进一种用于测量和校准亚纳升级每分钟微流量的光流控系统。
测量依赖于一个光流控系统，该系统在微流道的精确询问区域提供激发光并记录荧光。利用光漂白后流量和荧光发射之间的比例关系，系统能够实时确定流量。
在这里，我们展示了对流量控制器的改进，达到了 1%的不确定度。此外，使用扩散系数比我们之前的报告小 14 倍的分子，光流计的分辨率提高到了小于 1 纳升级/分钟，不确定度为 5%。
我们展示了在亚纳升级每分钟流量控制和测量方面的新能力，这些能力可推广应用于化学和生物医学行业的先进光-物质相互作用和分子扩散。
