Micro-Total-Analysis Systems Based on a Laser Valve for Single Cells Auto Injection and Analysis

This paper reports a micro-total-analysis system based on a laser valve, which can be triggered by the fluorescent signal emitting from labeled cells and switches a laser beam between two optical paths, for introduction and analyzing of single cells. While most microfluidic techniques are used for manipulation of cells analysis, injecting a cell is still time-consuming and labor-intensive because they are manually operated and depend on a microscope. Using a laser valve combining a power supply, we develop the method that can reproducibly and automatically transport single cells from sampling channel into analysis channel without through a microscope. Then, switching the laser beam to the point of detection and using it for components analysis of laser induced fluorescence (LIF). Human erythrocyte cells were used as a model. FITC-labeled components in the cellular membrane of single red cells were detected by using LIF.