The FOx BIOSYSTEMS instrument is effective in studying affinity and binding kinetics of proteins on large particles, such as microvesicles. The fluidics-free setup provides an advantage over existing biosensor platforms by eliminating the risk of clogging which is associated with complex targets, thereby removing the need for time-consuming rinsing procedures which may impact accuracy.
Case study:
Detecting extracellular vesicles
Extracellular vesicles are becoming increasingly important in the diagnosis, prognosis and therapy of many diseases, including cardiovascular disease and cancer. Their analysis is complicated by their range of size, composition and origin, compounded by the complexity of biofluids. Currently available methods have a range of downsides, including inaccuracy, complex/high-cost instruments or inability to process complex matrices.
The FOx BIOSYSTEMS instrument provides a fast and accurate method of detecting extracellular vesicles at physiologically relevant sensitivities. Its sensitivity is 103 – 104 times higher than that required for detection in healthy or cancer patients’ plasma. It was also shown to selectively capture breast cancer EVs spiked in blood plasma on the FO-SPR surface.
Extracellular vesicle detection. Capture antibodies covalently bound to the probe’s carboxyl monolayer bind the vesicle in a label-free configuration. The signal can be amplified using biotinylated detection antibodies and gold particles functionalized with anti-biotin antibodies.