Development of a cross flow filtration device for human blood cell fractionation

Separation of non-homogenous cell mixture using microfluidic platforms is a widely researched subject area due to numerous applications in both cell biology research and clinical medicine diagnostics. Blood is a non-homogenous mixture composed of various types of cells, plasma, proteins etc. Centrifugation and membrane separations are widely used techniques to fractionate blood. However equipment used in the above methods may require varying degrees of technical training, are not necessarily sterile, can have contamination or leakage problems and are generally used to analyze large amount of blood (3-5 ml) in a batch process. The problem we are addressing in our research is producing a label free, low-cost and high throughput device that can fractionate whole blood sample and separate pathogens from blood cells as a therapeutic method for treating bacteremia (presence of bacteria in blood). As a preliminary step we fractionate blood cells based on size from the whole blood. This is accomplished via cross-flow filtration. The device is made of Polydimethylsiloxane (PDMS). Separation mechanism of the device uses different pore size membranes incorporated between each compartment as physical barriers to fractionate particles from the sample specimen so that the particles which are to pass through or are blocked from the next compartment are controlled and subpopulations are collected for further analysis. Eventual goal of this device is to remove pathogens and inflammatory proteins in the blood. This device can improve the efficiency of medical technology involved in hematological studies. Therefore modifications of this device can lead to new therapeutic equipment.