4𝐷𝑡 . Thus, in principle, we should be able to predict the binding rate of any ink molecule to a wall in the solution using the diffusion coefficient. One such theory is the Ward-Tordai equation which has been modified from the Langmuir-Schaefer equation . However, both equations only roughly predict the binding kinetics giving values with large discrepancies from the experimental data, in some extreme cases, off by several orders of magnitude difference . In our previous Monte Carlo simulations, we identified the problem being the difficulty in predicting the concentration gradient near the interface . We came up with an equation for a special case to predict the barrierless adsorption rate of diffusive probes to an immobilized small target molecule being,