Fluidic sample handling

The focus of the design of fluidic devices will be to establish platforms for handling blood and faecal samples and bringing appropriate fractions of the material to the sensing surface (i.e. where the biosensor signal is generated). The vision is that all sample preparation processes will occur entirely on-chip and will be followed by efficient distribution of appropriate fluid fractions across the sensing surfaces.

Ultimately the test will be required to work on very small volumes of blood (e.g. from a finger prick). Blood measurements are most easily made on plasma after the removal of blood cells. There are a range of proven technologies for separation of blood cells from plasma. For faecal samples, on-chip filtration of solids is well understood, but the sensitivity of the electrochemical response can be affected by the faecal sample. Appropriate treatment of samples will be investigated to maintain sensitivity.

A key component of the work will be to consider the manufacturability of such devices alongside assessment of the physical and measurement performance, aiming to establish cost-effective platforms for manufacture. Additionally, to support development of the physical distribution of fluid across the sensing surface, fluid flow will be optimised by computer models.