Self‐Assembly of Poly(γ‐benzyl L‐glutamate)‐graft‐Poly(ethylene glycol) and Its Mixtures with Poly(γ‐benzyl L‐glutamate) Homopolymer

Abstract

Summary: Self‐association behaviors of poly(γ‐benzyl L‐glutamate)‐graft‐poly(ethylene glycol) (PBLG‐graft‐PEG) and its mixtures with PBLG homopolymer in aqueous media were investigated by fluorescence spectroscopy, transmission electron microscopy (TEM), and nuclear magnetic resonance (NMR) spectroscopy. It was revealed that PBLG‐graft‐PEG could self‐assemble to form polymeric micelles with a core‐shell structure in the shape of spindle. The introduction of PBLG homopolymer not only decreases the critical micelle concentration, but also changes the morphology of the micelles.The excitation fluorescence spectra of pyrene as a function of concentrations for the mixture of PBLG‐graft‐PEG with PBLG and a TEM image of the formed micelles.imageThe excitation fluorescence spectra of pyrene as a function of concentrations for the mixture of PBLG‐graft‐PEG with PBLG and a TEM image of the formed micelles.

Modification of hydrophobic polypeptide-based film by blending with hydrophilic poly(acrylic acid)

“…The PBLG homopolymer was synthesized by a standard N-carboxyl-γ-benzyl-L-glutamate anhydride (NCA) method [4] . The molecular weight of PBLG was estimated from the intrinsic viscosity measured in dichloroacetic acid (DCA) [22] .…”

“…In recent years, polypeptides and their copolymers have received much attention for their potential applications [1][2][3][4][5][6][7][8] .…”

Effects of reaction conditions on the grafting percentage of poly(ethylene glycol)-block-poly(γ-benzyl L-glutamate)-graft-poly(ethylene glycol) copolymer

“…PBLG-block-PEG copolymer (shown in Figure 1a) was obtained by the ring-opening polymerization of γ-BLG NCA initiated by AT-PEG (MW = 5000 g mol -1 ) in 1,4-dioxane at room temperature for 72 h. 1,19 PEG-b-PBLGg-PEG copolymer (shown by Figure 1b) was obtained by the ester exchange reaction of PBLG-block-PEG with mPEG (MW = 350 g mol -1 ) in 1,2-dichloroethane with p-toluenesulfonic acid as a catalyst according to the method described in references. 1,19 In the grafting reaction, the mole ratio of mPEG to PBLG segments is (20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30):1, the weight ratio of catalyst to PBLG segments is 5:1, PBLG/ dichloroethane is 1 g/200 mL, and the reaction temperature is controlled between 55 -60 °C with a precision of ±0.1 °C.…”

“…[1][2][3][4][5][6][7][8][9][10][11][12] Because of the unique structures and properties, synthesized polypeptides and their copolymers have been investigated widely in the fields of protein simulation, macromolecular conformational study, catalysis, drug delivery, nanoreactors etc. [13][14][15][16][17][18][19][20][21][22][23] Recently, much interest has been focused on the self-association behavior of the copolymers composed of hydrophobic polypeptide segments and hydrophilic polymer chains.…”

“…[13][14][15][16][17][18][19][20][21][22][23] Recently, much interest has been focused on the self-association behavior of the copolymers composed of hydrophobic polypeptide segments and hydrophilic polymer chains. 1,[7][8][9][10][11][12][13] Cho et al 9 have reported the formation of polymeric micelles composed of poly(γ-benzyl L-glutamate) and poly(ethylene oxide) in aqueous medium and the drug delivery system based on the core-shell nanoparticles with PBLG as the hydrophobic inner core and PEO as the hydrophilic outer shell. Kwon et al 13 reported that poly(β-benzyl L-aspartate) (PBLA)/poly(ethylene oxide) (PEO) diblock copolymers could self-assemble to form polymeric micelles composed of an outer shell of PEO and an inner core of PBLA in aqueous medium.…”