The surface charge and average size of ZnO was studied with a function of pH and time based on the interactions between ZnO and alginate. The pHPZC ZnO was the point of reference. At low concentrations of alginate (<0.001 mg/L) the positively charged ZnO aggregates were rapidly adsorbed below the pHPZC. With similar alginate concentrations, at pH=pHPZC, alginate was able to control the suspension behavior of the ZnO and promoted partial disaggregation in small volumes. This was more distinguishable as alginate form a surface coating on the nanoparticles and enhances stability via electrostatic stabilization mechanism which induces the disaggregation behavior in the ZnO nanoparticles and hence, decreases the aggregate size.