Microfluidic technology has emerged from the MEMS (Micro-Electro-Mechanical System)-technology as an important research field. During the last decade, various microfluidic technologies have been developed to open up a new era for biological studies. To understand the function of single cells, it is very important to monitor the dynamic behavior of a single cell in a living environment. Cell trapping in single cell analysis is urgently demanded There have been some review papers focusing on drug screen and cell analysis. However, cell trapping in single cell analysis has rarely been covered in the previous reviews. The present paper focuses on recent developments of cell trapping and highlights the mechanisms, governing equations and key parameters affecting the cell trapping efficiency by contact-based and contactless approach. The applications of the cell trapping method are discussed according to their basic research areas, such as biology and tissue engineering. Finally, the paper highlights the most promising cell trapping method for this research area.

Installing an inducer upstream of the main impeller is an effective approach for improving the performances of a centrifugal pump. In order to study the influence of inducer on the internal flow characteristics and evolution of vortex pump, the numerical simulation and experimental test of the 150WX-200-20 vortex pump have been done by the principle of computational fluid dynamics, to acquire performance and internal flow structure change of the vortex pump with inducer and without inducer. Based on these, the energy conversion of vortex pump is combined with the changes of the through-flow and circulating-flow of the internal flow structure. Through analyzing the influence of inducer on it, the energy conversion characteristic of vortex pump is revealed. The results show that adding the inducer can guarantee the power capacity of the vortex pump and improve the anticavitation performance, so as to improve the pump head and flows. Equipped with suitable for transporting solid liquid two phase flow of the screw centrifugal inducer, it can effectively weaken the existence of circulating-flow and significantly improve the flow situation in the impeller field. Adding inducer can weaken axial force of vortex pump and enhance stability of pump. And under the condition of no clogging, the conclusions are of great significance for improving the power capacity and fluid energy conversion of the vortex pump. In addition, it is a good method to weaken the axial force of the pump and enhance the stability of the pump system by adding the inducer.