**3.3 Flow confinement velocity impact**

To find the optimum flow confinement rate, beyond which the improvement of the binding kinetics becomes insignificant, the progression of the complex concentration for various flow confinement velocities has been plotted in **Figure 8**. It is evident that by increasing the flow confinement velocity from *uave* to 4 *uave*, the binding kinetics are improved (**Table 4**). Rapid flow confinement can, therefore, significantly improve the response time and therefore the performance of biosensor devices. However, beyond an optimal value (� 3*uave*) the improvement becomes insignificant. In summary, flow confinement confines the analyte molecules to a thin layer over the sensitive surface and thus raises the rate of the binding reaction.
