Chitosan-polymethylacrylic acid(CS-PMAA) polyelectrol yte nanoparticles were prepared by solution polymerization

the compositions and morphology were determined.FT-IR and XRD patterns confirmed the formation of polyelectrolyte composites

the experimental compositions for-NH2/-COOH of CS-PMAA were determined by automatic potentiometric titration and conductivity ti tration.DLS and TEM studies show that the nanoparticles are well dispersed and the dependence of particle size on pH values is observed.The results show that the nanoparticles have a high pH responsibility.The particle sizes are about 18 0 nm at pH=5

increase at pH of 3 and 9 and decrease at extreme pH values(pH3 and pH9).They have a broad perspective in application due to its small grain s ize

uniform structure

high pH responsibility and good biocompatibility.