| abstract |
A microfluidic system for separating, purifying and counting cell sub-populations, utilising steering of liquid flows in microfluidic channels in a cell focusing region (first dotted circle area); having the integration of the optical detection mechanism and a microchannel structure made from moulding. A master is photolithographically patterned on a soft PDMS silicon or polymer material. After being moulded and peeled off the master, the micro-channel structure is sealed on a hard substrate with openings punched through for wells ( 14, 12, 36, 38, 40 ). An optical detection region ( 20 ) discriminates different types of cells that have been formed into a single flow ( 30 ). Electromagnetic fields are used to steer ( 32 ) the flows of cells according to the signals from the optical detection region into branch channels leading to the punched wells for separate collection. The system can have parallel systems that increase throughput or cascade systems to provide several analysis steps. The optical system an micro-lens ( 24 ) for the system can be imbedded in the moulding material during formation of the mould. |