FIGURE 5. Example of an integrated disposable diagnostic card.

a, Image of a card. The red O-rings are for interfacing with off-card components (for example, valves and pumps) that will eventually be incorporated onto the card itself. b, Schematic of the card. The card accepts filtered saliva (see Table 2) from the syringe and contains an H-filter for further sample conditioning, a herringbone mixer for mixing antibodies with the sample, and channels with gold-coated surfaces for detection of analyte in the sample using an SPR imaging-based immunoassay (manuscript in preparation, T.E. et al.). Numbers in ovals are flow rates in nl s^-1. Numbers at the H-filter's four ports are the percentages of flow entering (right) and exiting (left) the device. MB, mixing buffer; HB, H-filter buffer; HV, H-filter vacuum; R1 and R2 are reference solutions, typically a positive and negative control.