MEASURING EV COUNT
The number of antigen positive EVs that have bound to the multiplexed chip can be measured direct from sample with no purification. Control tests are performed to ensure that the binding events measured are specific and not related to non-specific binding or aggregates associated with the antibody used to functionalize the chip surface. The array is measured prior to sample incubation and any contaminant events can be excluded from the analysis. Similarly, non-specific binding events observed on the negative control can be subtracted from experimental results.
The graph below shows the linearity response of the ExoView instrument. As a measure of comparability, a sample of EVs was measured using an NTA instrument. The sample has been linearly diluted and measured using the ExoView platform and the number of CD81-positive EVs were counted at a range of dilutions.