PMC:7556614 / 20608-21456 JSONTXT

{"project":"2_test","denotations":[{"id":"33057878-29079515-28015","span":{"begin":111,"end":113},"obj":"29079515"}],"text":"PEG can provide stealth property on nanoparticles to avoid RES elimination and prolong their circulation time (29). Protonation on chitosan-free amino group in the acidic environment caused it to be positively charged. The dipole-dipole or hydrogen bonding between chitosan shell and PEG became stronger than intra-molecular or intermolecular hydrogen bonding of chitosan chain and allowed PEG grafting onto it due to interaction between amine or amide nitrogen of chitosan, and hydroxyl and etheric oxygen of PEG (30). Probe sonication was employed to reduce particle size as well as improving uniformity of size. PALNs formulated exhibited a pale white appearance with soapy texture. Pale white colour resulted from the massive amount of nanoparticles formed, while the frothy white texture was due to the presence of PEG 2000 in the formulation."}