Aggregation behavior in water of amphiphilic diblock copolymers bearing biocompatible phosphorylcholine and cholesteryl groups

• Published in: Polymer journal Vol. 47; no. 1; pp. 71 - 76
• Main Authors: Ohno, Sayaka, Hasegawa, Shoto, Liu, Huihua, Ishihara, Kazuhiko, Yusa, Shin-ichi
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01.01.2015; Nature Publishing Group
• Subjects: 140/131; 631/45; Addition polymerization; Aggregates; Aqueous solutions; Biocompatibility; Biomaterials; Bioorganic Chemistry; Block copolymers; Blocking; Chain transfer; Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Control rods; Copolymers; Degree of polymerization; Dissolution; Fluorescent indicators; Light scattering; Micelles; Morphology; original-article; Phosphorylcholine; Photon correlation spectroscopy; Polymer Sciences; Polymerization; Polymers; Reagents; Scattering; Surfaces and Interfaces; Thin Films
• ISSN: 0032-3896; 1349-0540
• DOI: 10.1038/pj.2014.92

Poly(2-(methacryloyloxy)ethyl phosphorylcholine)- block -poly(cholesteryl 6-methacryloyloxyhexanoate) (PMPC 82 - b -PChM n ) copolymers with different PChM block lengths were prepared via reversible addition–fragmentation chain transfer controlled/living radical polymerization using a PMPC-based macro-chain transfer agent. The subscript number and n (=3 and 6) refer to the degree of polymerization of the PMPC and PChM blocks, respectively. PMPC 82 - b -PChM n cannot dissolve in water directly due to the strong hydrophobic nature of the PChM block. To prepare the aqueous solution, the diblock copolymer was dissolved in an organic solvent and then dialyzed against pure water. These diblock copolymers formed spherical and rod-like micelles in water, depending on the composition of cholesteryl (Chol) group in the polymer. The prepared aggregates were characterized using static light scattering, dynamic light scattering, transmission electron microscopy and fluorescence probe techniques. The characterization results suggest that the morphology of the polymer aggregates can be controlled from spherical to rod-like micelles by increasing the number of Chol groups in the polymer. Poly(2-(methacryloyloxy)ethyl phosphorylcholine)- block -poly(cholesteryl 6-methacryloyloxyhexanoate) (PMPC 82 - b -PChM n ) with different PChM block lengths was prepared via controlled/living radical polymerization. To prepare the aqueous solution, the diblock copolymer was dissolved in an organic solvent and then subject to dialyze against pure water. These diblock copolymers formed spherical and rod-like micelles in water depending on the composition of cholesteryl (Chol) group in the polymer. The morphology of the polymer aggregates could be controlled from spherical to rod-like micelles with increasing amount of Chol groups in the polymer.