Case Studies

Single Use Cartridge: Passive Whole Blood Processing + Sensor integration

Objectives: A disposable system for collecting a sample of 2-10uL of whole blood, diluting 20-40x, mixing and delivery to a sensor mounted on a circuit board.

Challenges: (i) The sample must be mixed completely without active pumping. (ii) The sensor is wire bonded and mounted on a circuit board, creating an irregular surface around the perimeter of the sensing surface.

Solutions: (i) A blood metering device draws sample with +/- 2% variability, which is then diluted with buffer and delivered to the cartridge. (ii) A three component cartridge, about the size of a USB stick was developed which included a leak-proof seal to enclose the sensing surface, and provide for air-bubble trapping and sample overflow.

Single-Use Cartridge: Water Quality Test + Active Fluid Control

Objective: A disposable system which manages the downstream metering mixing and delivery to the sensor from a concentrated water sample.

Challenges: Integrate multi-step workflow into a disposable suitable for use with a backpack-based instrument system.

Solution: Develop a cartridge that performs binding assays using on board, pneumatically controlled valves with a rugged instrument interface. Semi-automated control is used to perform all steps required for the assay (volume metering, mixing, capture, washing, detection).

Highly Multiplexed Fluid-Handling Manifolds

Objective: Highly multiplexed valve manifolds for programmable fluid delivery from multiple inlets to multiple output ports.

Challenges: Minimize dead volume and separate the electro-mechanical controls from the fluids.

Solution: A manifold with on-board pneumatic valves, actuated by external electro-mechanical controls. 32 fluid streams can be managed and combined by addressing different sets of on board pneumatically controlled valves and delivered to multiple output ports.

Cell Culture & Organ-on-Chip

Objective: Multi-chamber flow-cells for parallelized study of cell culture and interaction.

Challenges: Use a single inlet and outlet to provide equal flow rate to each chamber while preventing direct interaction between different compartments.

Solution: Integration of custom membranes at the inlets and outlets of each chamber to control fluidic resistance and providing cell confinement. Applications include liver co-cultures, and lung co-culture.