Block copolymers of ethylene oxide and phenyl glycidyl ether: micellization, gelation, and drug solubilization.
Three triblock copolymers of ethylene oxide and phenyl glycidyl ether, type E(m)G(n)E(m), where G = OCH2CH(CH2OC6H5) and E = OCH2CH2, were synthesized and characterized by gel-permeation chromatography, matrix-assisted laser desorption ionization time-of-flight mass spectrometry, and NMR spectroscopy. Their association properties in aqueous solution were investigated by surface tensiometry and light scattering, yielding values of the critical micelle concentration (cmc), the hydrodynamic radius, and the association number. Gel boundaries in concentrated micellar solution were investigated by tube inversion, and for one copolymer, the temperature and frequency dependence of the dynamic moduli served to confirm and extend the phase diagram and to highlight gel properties. Small-angle X-ray scattering was used to investigate gel structure. The overall aim of the work was to define a block copolymer micellar system with better solubilization capacity for poorly soluble aromatic drugs than had been achieved so far by use of block copoly(oxyalkylene)s. Judged by the solubilization of griseofulvin in aqueous solutions of the E(m)G(n)E(m) copolymers, this aim was achieved.
Taboada
Pablo
P
Department of Physics of Condensed Matter, University of Santiago de Compostela, E-15706 Santiago de Compostela, Spain.
Velasquez
Gemma
G
Barbosa
Silvia
S
Castelletto
Valeria
V
Nixon
S Keith
SK
Yang
Zhuo
Z
Heatley
Frank
F
Hamley
Ian W
IW
Ashford
Marianne
M
Mosquera
Victor
V
Attwood
David
D
Booth
Colin
C
D000935:Antifungal Agents / Q000737:chemistry; D015195:Drug Design; D005026:Ethylene Glycols / Q000737:chemistry*; D005027:Ethylene Oxide / Q000737:chemistry*; D005782:Gels; D006118:Griseofulvin / Q000737:chemistry; D008823:Micelles; D015394:Molecular Structure; D010647:Phenyl Ethers / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D012995:Solubility
D000935:Antifungal Agents; D005026:Ethylene Glycols; D005782:Gels; D008823:Micelles; D010647:Phenyl Ethers; D011108:Polymers; C031474:styrene glycol; D006118:Griseofulvin; D005027:Ethylene Oxide