A comparative study of chitosan shielding effect on nano-carriers hydrophilicity and biodistribution

► Chitosan compared to other shielding materials was exploited for shielding PLA NPs. ► The shielding effect on particles zeta potential and hydrophilicity was studied. ► The outcome of protection on NPs pharmacokinetics and biodistribution was examined. ► Both chitosan and polysorbate-coated NPs exhibited comparable hydrophilic characters. ► In vivo uptake in RES was inhibited with chitosan-coated NPs.