Synthesis and structural study of an ABA block copolymer consisting of poly(ε‐benzyloxycarbonyl‐L‐lysine) as the a block and poly(ethylene oxide) as the B block

Abstract

ABA-type block copolymers composed of poly(6-benzyloxycarbonyl-L-lysine) (PCLL) as the A component and poly(ethy1ene oxide) as the B component were synthesized by polymerization of 6-benzyloxycarbonyl-L-lysine N-carboxyanhydride initiated by primary amino groups located at both ends of the PEO chain. From circular dichroism measurements in solution, as well as from infrared spectra measurements in the solid state, it was found that the polypeptide block exists in the a-helical conformation, as in PCLL homopolymer. The intensity of wide-angle X-ray diffraction patterns of the block copolymers depends on the PEO content and shows basically similar reflections as the PCLL homopolymer. The morphology examined by transmission electron microscopy and differential scanning calorimetry revealed microphase-separated structure.

Self‐Assembly of a Hydrophobic Polypeptide Containing a Short Hydrophilic Middle Segment: Vesicles to Large Compound Micelles

“…[22] A conventional method is used to prepare its micellar solution. Firstly, the polymer is dissolved in a common solvent (DMF), and then a selective solvent (water) is added.…”

Microstructure characterization and thermal analysis of hybrid block copolymer α-methoxy-poly(ethylene glycol)-block-poly[ε-(benzyloxycarbonyl)-l-lysine] for biomedical applications

“…PEG and PLL have been covalently combined to form graft [24,25], diblock [26][27][28][29], triblock [30][31][32], and random [33] copolymers and dendrimers [34,35]; some of which have been conjugated to other moieties, such as: folates [36], acids [37,38], sugars [39,40], RGD [41,42], and amphotericin B [43], to mention a few. They have also been used in polyion complex (PIC) formation [27,44,45], and investigated for drug [46,47] and gene [48][49][50] delivery, colloidal lithography [51,52], biomimetic applications [53], photodynamic therapy (PDT) [54,55], antithrombogenicity [56], and as bioimaging agents [57,58].…”

Synthesis and micellization behavior of stimuli-responsive polypeptide hybrid triblock copolymer

“…The first one involves nanostructures with corona-forming poly-peptide segments, starting from amphiphilic copolymers consisting of hydrophobic synthetic block and hydrophilic blocks polypeptide block such as poly(L-glutamic acid)(PLGA) or poly(L-lysine) (PLL) [12][13][14][15][16][17][18] . The second type typically involves water-insoluble polypeptide sequence as one of the building blocks [19,20] .Our recent research interests partially involve double hydrophilic block copolymers (DHBCs) [21][22][23] . Subjected to physical or chemical transformations in aqueous solution, one of the blocks of DHBCs can be selectively rendered water insoluble, while the other block still remains hydrophilic to stabilize the self-assembled aggregates.…”

“…The first one involves nanostructures with corona-forming poly-peptide segments, starting from amphiphilic copolymers consisting of hydrophobic synthetic block and hydrophilic blocks polypeptide block such as poly(L-glutamic acid)(PLGA) or poly(L-lysine) (PLL) [12][13][14][15][16][17][18] . The second type typically involves water-insoluble polypeptide sequence as one of the building blocks [19,20] .…”