Sambrano Jesus, Rodriguez Felicia, Martin John, Houston Jessica P
Department of Chemical and Materials Engineering, New Mexico State University, Las Cruces, NM, United States.
Tiber Plasma Diagnostics, Las Cruces, NM, United States.
Front Phys. 2021 May;9. doi: 10.3389/fphy.2021.647985. Epub 2021 May 14.
Conventional flow cytometry is a valuable quantitative tool. Flow cytometers reveal physical and biochemical information from cells at a high throughput, which is quite valuable for many biomedical, biological, and diagnostic research fields. Flow cytometers range in complexity and typically provide multiparametric data for the user at rates of up to 50,000 cells measured per second. Cytometry systems are configured such that fluorescence or scattered light signals are collected per-cell, and the integrated optical signal at a given wavelength range indicates a particular cellular feature such as phenotype or morphology. When the timing of the optical signal is measured, the cytometry system becomes "time-resolved." Time-resolved flow cytometry (TRFC) instruments can detect fluorescence decay kinetics, and such measurements are consequential for Förster Resonance Energy Transfer (FRET) studies, multiplexing, and metabolic mapping, to name a few. TRFC systems capture fluorescence lifetimes at rates of thousands of cells per-second, however the approach is challenged at this throughput by terminal cellular velocities. High flow rates limit the total number of photons integrated per-cell, reducing the reliability of the average lifetime as a cytometric parameter. In this contribution, we examine an innovative approach to address this signal-to-noise issue. The technology merges time-resolved hardware with microfluidics and acoustics. We present an "acoustofluidic" time-resolved flow cytometer so that cellular velocities can be adjusted on the fly with a standing acoustic wave (SAW). Our work shows that acoustic control can be combined with time-resolved features to appropriately balance the throughput with the optical signals necessary for lifetime data.
传统流式细胞术是一种有价值的定量工具。流式细胞仪能够高通量地揭示细胞的物理和生化信息，这对许多生物医学、生物学和诊断研究领域都非常有价值。流式细胞仪的复杂程度各不相同，通常以每秒高达50000个细胞的测量速度为用户提供多参数数据。流式细胞术系统的配置方式是，每个细胞收集荧光或散射光信号，给定波长范围内的积分光信号表示特定的细胞特征，如细胞表型或形态。当测量光信号的时间时，流式细胞术系统就变成了“时间分辨”的。时间分辨流式细胞术（TRFC）仪器可以检测荧光衰减动力学，此类测量对于荧光共振能量转移（FRET）研究、多路复用和代谢图谱绘制等诸多方面都具有重要意义。TRFC系统以每秒数千个细胞的速度捕获荧光寿命，然而，在这种通量下，该方法受到细胞最终速度的挑战。高流速限制了每个细胞积分的光子总数，降低了平均寿命作为细胞测量参数的可靠性。在本论文中，我们研究了一种创新方法来解决这个信噪比问题。该技术将时间分辨硬件与微流体学和声学相结合。我们展示了一种“声流体”时间分辨流式细胞仪，这样可以利用驻声波（SAW）即时调整细胞速度。我们的工作表明，声学控制可以与时间分辨功能相结合，以适当平衡通量与寿命数据所需的光信号。
