effect of preparation parameters on ultra low molecular weight chitosan/hyaluronic acid nanoparticles and dye removal from wastewater

Aim and background: studies have unequivocally shown that chitosan can serve as a potent coagulant for organic substances and an efficient adsorbent for dyes found in diverse wastewater streams. in this specific application, chitosan appears more effective than other adsorbent such as activated charcoal.methods: in this study, nanoparticles of ultra-low molecular weight chitosan (ulmwcs)/hyaluronic acid (ha) were prepared by ion gelation. three independent variables, namely, ratio of concentration of ulmwcs to ha (cs/ha), ph of solution and stirring time were studied to identify their effects on size, polydispersity and zeta potential of prepared nanoparticles using a box-behnken design.results and discussion: results showed that ph and cs/ha have a direct effect on size, while increase of stirring time decreases the size of nanoparticles. additionally, it was shown that all the independent parameters have direct effects on zeta potential. also, the minimum polydispersity index was observed at lowest values of cs/ha. the model also predicted that the optimum values are 4.15, 4.14 and 180 (min) for the cs/ha, solution ph and stirring time, respectively. the obtained preparation had a size of 200 nm, polydispersity index of 0.37, and zeta potential of 13.0 mv. dye removal was over 80% by using ulmwcs nanoparticles/ hyaluronic acid (ha).conclusion: use of ulmwcs nanoparticles/ ha for treating dye contaminants in wastewater, was an extremely promising area of current research and actual plant operation.