Abstract: A microfluidic diagnostic device comprises a base and at least one switch coupled to a portion of the base, the switch comprising a flap that is pivotable with respect to the base from a first position spaced away from the base a first distance to a second position where the flap is spaced away from the base a second distance. Both the base and the switch comprise one or more channels that permit passive transportation of an aqueous solution. The switch may be formed by bending or deforming a strip to cause the flap to be in the first position when there is less than a predetermined amount of fluid within the channel of switch. When a predetermined amount of fluid is in the channel of the switch, the flap pivots to the second position, which may be achieved through power from gravity, capillarity, and/or inherent elastic energy.

Abstract: A microfluidic diagnostic device comprises a base and at least one switch coupled to a portion of the base, the switch comprising a flap that is pivotable with respect to the base from a first position spaced away from the base a first distance to a second position where the flap is spaced away from the base a second distance. Both the base and the switch comprise one or more channels that permit passive transportation of an aqueous solution. The switch may be formed by bending or deforming a strip to cause the flap to be in the first position when there is less than a predetermined amount of fluid within the channel of switch. When a predetermined amount of fluid is in the channel of the switch, the flap pivots to the second position, which may be achieved through power from gravity, capillarity, and/or inherent elastic energy.