title: pH-Responsive Polyethylene Glycol Monomethyl Ether-ε-Polylysine-G-Poly (Lactic Acid)-Based Nanoparticles as Protein Delivery Systems.
abstract: The application of poly(lactic acid) for sustained protein delivery is restricted by the harsh pH inside carriers. In this study, we synthesized a pH-responsive comb-shaped block copolymer, polyethylene glycol monomethyl ether-ε-polylysine-g-poly (lactic acid) (PEP)to deliver protein (bovine serum albumin (BSA)). The PEP nanoparticles could automatically adjust the internal pH to a milder level, as shown by the quantitative ratio metric results. The circular dichroism spectra showed that proteins from the PEP nanoparticles were more stable than those from poly(lactic acid) nanoparticles. PEP nanoparticles could achieve sustained BSA release in both in vitro and in vivo experiments. Cytotoxicity results in HL-7702 cells suggested good cell compatibility of PEP carriers. Acute toxicity results showed that the PEP nanoparticles induced no toxic response in Kunming mice. Thus, PEP nanoparticles hold potential as efficient carriers for sustained protein release.
authors.affiliation: Laboratory of Cancer Cell Biology, Tianjin Key Laboratory of Cancer Prevention and Therapy, National Clinical Research Center for Cancer, Tianjin Medical University Cancer Institute and Hospital, Tianjin, 300060, China.
authors.forename: Huiqin
authors.initials: H
authors.lastname: Liu
authors.affiliation: Institute of Biomedical Engineering, Tianjin Medical University, Tianjin, 300070, China.
authors.forename: Yijia
authors.initials: Y
authors.lastname: Li
authors.affiliation: Research Center of Basic Medical Sciences, Tianjin Medical University, Tianjin, 300070, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Yang
authors.affiliation: Institute of Biomedical Engineering, Tianjin Medical University, Tianjin, 300070, China.|Research Center of Basic Medical Sciences, Tianjin Medical University, Tianjin, 300070, China.
authors.forename: Xiujun
authors.initials: X
authors.lastname: Gao
authors.affiliation: Laboratory of Cancer Cell Biology, Tianjin Key Laboratory of Cancer Prevention and Therapy, National Clinical Research Center for Cancer, Tianjin Medical University Cancer Institute and Hospital, Tianjin, 300060, China.
authors.forename: Guoguang
authors.initials: G
authors.lastname: Ying
mesh_terms: D000818:Animals; D001672:Biocompatible Materials / Q000493:pharmacokinetics; D002460:Cell Line; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D051379:Mice; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles / Q000737:chemistry*; D011091:Polyesters / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry*; D011107:Polylysine / Q000737:chemistry*; D017433:Protein Structure, Secondary; D011506:Proteins / Q000008:administration & dosage* / Q000737:chemistry; D014867:Water / Q000737:chemistry
chemical_list: D001672:Biocompatible Materials; D011091:Polyesters; D011506:Proteins; D014867:Water; D011107:Polylysine; D011092:Polyethylene Glycols; C033616:poly(lactide); C028210:monomethoxypolyethylene glycol