Stabilization of peptide-based vesicles via in situ oxygen-mediated cross-linking.
Reversible vesicles from poly(L-glutamic acid)(65) -block-poly[(L-lysine)-ran-(L-3,4-dihydroxyphenylalanine)](75) [PLGA(65)-b-P(LL-r-DOPA)(75)] block copolypeptide adopt different configurations depending on the surrounding pH. At pH = 3, AFM and TEM images show ellipsoidal morphologies, whereas at pH = 12 both TEM and AFM reveal the formation of hollow vesicles. At pH = 12, the P(LL-r-DOPA) block forms the internal layer of the vesicle shell and the subsequent oxygen-mediated oxidation of the phenolic groups of the DOPA lead to the formation of quinonic intermediates, which undergo intermolecular dimerization to stabilize the vesicles via in situ cross-linking. Consequently, the vesicles maintain their shape even when the pH is reversed back to 3, as confirmed by AFM and TEM.
Department of Chemical and Biomolecular Engineering, University of Melbourne, Parkville 3010, Australia.
Adrian
A
Sulistio
Anton
A
Blencowe
Jiapei
J
Wang
Gary
G
Bryant
Xiaoqing
X
Zhang
Greg G
GG
Qiao
D002850:Chromatography, Gel; D006863:Hydrogen-Ion Concentration; D009682:Magnetic Resonance Spectroscopy; D018625:Microscopy, Atomic Force; D046529:Microscopy, Electron, Transmission; D010100:Oxygen / Q000737:chemistry*; D010455:Peptides / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet
D010455:Peptides; D011108:Polymers; D010100:Oxygen