Bio-particle separation using microfluidic porous plug for environmental monitoring

This paper deals with (i) fabrication of microfluidic devices using living radical photo-polymerization method with various polymers (aromatic urethane diacrylate, photo-initiator, and photo-iniferter), and placement of porous plug using salt-leaching technique in microfluidic channel, (ii) determination of the pore size of the porous plug using flow field-flow fractionation, and (iii) investigation of separation of various particles including latex micro-particles and bacteria. It was demonstrated that the microfluidic device with porous plug could be used as a new and simple tool for particles (including microorganisms) separation based on their sizes and a miniaturized filter for water sample analyses.

We have developed a new method for the particle (including microorganisms) separation using porous plug in microfluidic device. The porous plug was fabricated in microfluidic channels using LRPP and salt leaching method. The pore size of porous plug media could be controlled by the KCl sizes obtained through two sieves with different mesh size. This method can easily be applied both for a miniaturized filter for water sample analyses and size-dependent separation of particles and microorganisms in water samples. Furthermore, this porous plug can be used for not only concentrating protozoan cysts and crypto cysts but also separating proteins based on molecular size for life science studies.