Modeling Langmuir isotherms with the Gillespie stochastic algorithm

• Ability to model biomolecules adsorption tested for Gillespie stochastic algorithm.
• Gillespie approach effective in modeling isotherms consistent with Langmuir theory.
• Uptake curves not following Langmuir theory tenets modeled with Gillespie algorithm.
• Gillespie stochastic algorithm applicable to gas multicomponent adsorption.

The overall goal of this work is to develop a robust modeling approach that is capable of simulating single and multicomponent isotherms for biological molecules interacting with a variety of adsorbents. Provided the ratio between the forward and reverse adsorption/desorption constants is known, the Gillespie stochastic algorithm has been shown to be effective in modeling isotherms consistent with the Langmuir theory and uptake curves that fall outside this traditional approach. We have used this method to model protein adsorption on ion-exchange adsorbents, hydrophobic interactive adsorbents and ice crystals. In our latest efforts we have applied the Gillespie approach to simulate binary and ternary isotherms from the literature involving gas–solid adsorption applications. In each case the model is consistent with the experimental results presented.