title: Stimuli-responsive peptide-based ABA-triblock copolymers: unique morphology transitions with pH.
abstract: We report the synthesis and solution characterization of poly(L-lysine)-b-poly(propylene oxide)-b-poly(L-lysine) (KPK) triblock copolymers with high lysine weight fractions (>75 wt%). In contrast to PK diblock copolymers in this composition range, KPK triblock copolymers exhibit morphology transitions as a function of pH. Using a combination of light-scattering and microscopy techniques, we demonstrate spherical micelle-vesicle and spherical micelle-disk micelle transitions for different K fractions. We interpret these morphology changes in terms of the energy penalty associated with folding the core P block to form a spherical micelle in relation to the interfacial curvature associated with different charged states of the K block.
authors.affiliation: School of Polymers and High Performance Materials, The University of Southern Mississippi, 118 College Drive #5050, Hattiesburg, MS 39406, USA.
authors.forename: Jacob G
authors.initials: JG
authors.lastname: Ray
authors.forename: Sandeep S
authors.initials: SS
authors.lastname: Naik
authors.forename: Emily A
authors.initials: EA
authors.lastname: Hoff
authors.forename: Ashley J
authors.initials: AJ
authors.lastname: Johnson
authors.forename: Jack T
authors.initials: JT
authors.lastname: Ly
authors.forename: Charles P
authors.initials: CP
authors.lastname: Easterling
authors.forename: Derek L
authors.initials: DL
authors.lastname: Patton
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Savin
mesh_terms: D002942:Circular Dichroism; D006863:Hydrogen-Ion Concentration; D008027:Light; D008823:Micelles; D018625:Microscopy, Atomic Force; D008968:Molecular Conformation; D008970:Molecular Weight; D054118:Nanospheres / Q000737:chemistry / Q000648:ultrastructure; D011107:Polylysine / Q000031:analogs & derivatives* / Q000737:chemistry; D058105:Polymerization; D011409:Propylene Glycols / Q000737:chemistry*; D012542:Scattering, Radiation
chemical_list: D008823:Micelles; D011409:Propylene Glycols; D011107:Polylysine