A simple fabrication and reusable microfluidic three-dimensional hydrodynamic focus device is proposed in this study, which can be used for fluorescent particle counting and fluorescence intensity detection. The three-dimensional hydrodynamic focus microfluidic device offers numerous advantages over devices with a two-dimensional focus function. However, the fabrication process of most such devices is relatively complicated. In this study, a three-dimensional hydrodynamic focus device is fabricated by assembling commercially available square, round, and tapered glass capillaries. The inner diameter of the square capillary matches the outer diameter of the circular capillary to ensure that the centers of different capillaries are on the same axis. Thus, the device can provide a symmetric three-dimensional hydrodynamic focus flow. The proposed device can control the diameter of the focused flow by changing the flow rate of the sheath and sample flow. Standard fluorescent beads and fluorescent cells are passed through this device to accurately count the number of fluorescent particles and detect the intensity of fluorescence.

提出了一种简单的可重复使用的微流体三维流体动力聚焦装置，该装置可用于荧光颗粒计数和荧光强度检测。相对于具有二维聚焦功能的装置，三维流体动力聚焦微流体装置具有众多优势。但是，大多数这种装置的制造过程相对复杂。在这项研究中，通过组装市售的方形，圆形和锥形玻璃毛细管来制造三维流体动力聚焦装置。方毛细管的内径与圆形毛细管的外径匹配，以确保不同毛细管的中心在同一轴上。因此，该装置可以提供对称的三维流体动力聚焦流。所提出的装置可以通过改变护套的流速和样品流来控制聚焦流的直径。标准荧光珠和荧光池通过此设备，以准确计数荧光颗粒的数量并检测荧光强度。