Ion dissociation is a mechanism of entropic-electrostatic nature that occurs when neutral molecules are dissolved in a polar medium. The break up of ionic bond results in entropy gain from a counterion released into solution. In apolar medium, the entropic gain is not sufficient to compensate for the electrostatic penalty of exposing charge to a low dielectric environment . On the other hand, in a strongly polar medium, such as water, the entropic gain can compensate the electrostatic self-energy penalty, resulting from breaking of ionic bonds . Dissolving salt into an aqueous solution provides an efficient way of controlling electrostatic forces between charged surfaces, as the local electrochemical equilibrium results in partial screening of these interactions via formation of ion neutralizing clouds . On the other hand, the charging mechanism of surfaces with weak acidic/basic groups also involves -in addition to entropic and electrostatic contributions -covalent bonding between protons and active surface groups . For surfaces with acidic groups, considered in the present paper, proton exchange between donor and receptor molecules results in either charging (deprotonation) or neutralization (protonation) of macromolecules. The important characteristic of this process is that the charge of a nanoparticle or a surface decorated with acid/base groups can be controlled by the amount of the acid/base added to the solution, i. e. the system's pH. Such controlling mechanism is generally referred to as the Charge Regulation (CR) mechanism . The possibility of tuning the charge of nanoparticles by varying pH -alongside with the adjustment of the effective strength and range of Coulomb interactions by added salt -represents a convenient way of controlling the effective interactions between nanoparticles and surfaces in general . As an example, the irreversible aggregation of particles such as charged colloidal suspensions subject to the gravitational field can be controlled by changing system's pH and the amount of added electrolyte .