ABSTRACT
Objective To investigate the influence of ionic strength on the stability of the methotrexate-loaded dendrimer nanoparticles. Methods The influences of different ions (Na+,Cl-) and different concentrations of sodium chloride on the stability of the nanoparticles were studied. The particle size was measured by dynamic light scattering(DLS) and drug-loading content was determined by high-performance liquid chromatography (HPLC) in order to evaluate the stability. Results The Cl- was finally verified to play an important role in stabilizing the nanoparticles and the effective concentration of the sodium chloride was recommended to be below 1. 80% . Conclusion The recommended concentration (less than 1. 80% ) of the sodium chloride significantly improves the stability of the nanoparticles and benefits for long term storage.