Implementation of Pulsatile Flow on Microfilters for Efficient Cell Sorting
Lee, Jun Yeob
MetadataShow full item record
Cell sorting has been an important process in both clinical testing and medical diagnostics, and is used in many applications ranging from emergency trauma evaluation to cystic fibrosis checkups. Currently, efficient blood cell sorting needs to be done in a laboratory setting with dedicated machinery, and the process is expensive, labor intensive and time consuming. Multiple microfluidic solutions have been proposed to address these issues, including separation through hydrodynamics, magnetism, and dielectrophoresis. Although these devices alleviate some of the problems surrounding laboratory blood sorting, the chips remain complex, costly, and lacks the specificity needed to be used directly in a clinical setting. The purpose of this study is to investigate the effectiveness of a new cell sorting method: pulse width modulated periodic backflush in a dead-end filtration system. Dead-end filtration is a cheaper, simpler approach to cell sorting; particles are passed directly through a membrane filter which blocks larger particles while passing smaller ones. Dead-end filtration is easy to implement, and often has higher sorting efficiencies. The problem of particle throughput reduction due to clogging is alleviated by a periodic backflush mechanism that maintains high sorting efficiency while retaining particle throughput. We examine the impact of superimposing periodic backflush in a large fluidic system and create a prototype to validate this effect in a microfluidic environment. We use a mixture of staph epidermidis and lung epithelial cells to validate the application of backflush filtration in a clinical environment.