Patent ID: 7037417

Claim:
A micro-analytical apparatus for mechanically manipulating fluid samples, comprising: a substrate having at least first and second covered channels, each having openings at opposite ends thereof, said first and second covered channels intersecting to form a common intersection with at least four arms; wherein at least three of the openings of said first and second covered channels are connected to a multi-port valve to control the pressure in the channels, said multi-port valve having at least eight ports; and said multi-port valve being the sole actuator controlling the direction of flow of fluid samples in all the arms of said intersection, and controlling the directions of flow in all of said arms simultaneously; and wherein said multi-port valve is switchable between: a first position, wherein the multi-port valve provides a path for mechanical pumping of a first fluid through said multi-port valve in said first covered channel, while a first opening of said second covered channel is connected through said multi-port valve to mechanical pumping means and the second opening of said second covered channel is directly connected to mechanical pumping means so as to pinch said first fluid sample at said common intersection; and a second position where the openings of said first covered channel are connected through said multi-port valve so as to form a closed loop, while said first opening of said second covered channel is disconnected from any mechanical pumping means and the second opening of said second covered channel is directly connected to a mechanical pumping means so as to transport a second fluid in said second covered microchannel while maintaining constant pressure in both arms of said first channel.