title: Polymeric hollow spheres assembled from ALG-g-PNIPAM and β-cyclodextrin for controlled drug release.
abstract: In this paper, thermo-sensitive polymeric hollow spheres assembled from sodium alginate-graft-poly(N-isopropylacrylamide) (ALG-g-PNIPAM) and β-cyclodextrin (β-CD) were prepared for controlled release of 5-fluorouracil (5-FU). In aqueous solutions, β-CD and PNIPAM formed rod-like segments through inclusion complexation interactions and sodium alginate acted as coil segments, which resulted in the formation of hollow structures. The size and wall thickness of assemblies increased with the increase of β-CD in mixtures. The lower critical solution temperature (LCST) of hollow spheres varied in the range of 35-37°C. The hollow spheres exhibited high drug loading efficiency for 5-FU due to the hydrophilic cavities. The initial composition of mixtures, temperature and pH had a significant effect on the inclusion ability and drug release. Increasing temperatures above the LCST or decreasing pH to acidic conditions, a more rapid release rate was observed.
authors.affiliation: School of Chemistry and Materials Science, Ludong University, Yantai 264025, China. Electronic address: guiyingli@126.com.
authors.forename: Guiying
authors.initials: G
authors.lastname: Li
authors.affiliation: School of Chemistry and Materials Science, Ludong University, Yantai 264025, China.
authors.forename: Nana
authors.initials: N
authors.lastname: Yu
authors.affiliation: School of Chemistry and Materials Science, Ludong University, Yantai 264025, China.
authors.forename: Yurong
authors.initials: Y
authors.lastname: Gao
authors.affiliation: School of Chemistry and Materials Science, Ludong University, Yantai 264025, China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Tao
authors.affiliation: School of Chemistry and Materials Science, Ludong University, Yantai 264025, China.
authors.forename: Xunyong
authors.initials: X
authors.lastname: Liu
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry*; D000464:Alginates / Q000737:chemistry*; D003692:Delayed-Action Preparations; D004337:Drug Carriers / Q000737:chemistry*; D065546:Drug Liberation; D005472:Fluorouracil / Q000008:administration & dosage / Q000493:pharmacokinetics; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D011108:Polymers / Q000737:chemistry*; D013696:Temperature; D047392:beta-Cyclodextrins / Q000737:chemistry*
chemical_list: D000180:Acrylic Resins; D000464:Alginates; D003692:Delayed-Action Preparations; D004337:Drug Carriers; D006603:Hexuronic Acids; D011108:Polymers; D047392:beta-Cyclodextrins; C052970:poly-N-isopropylacrylamide; D020723:Glucuronic Acid; D005472:Fluorouracil
keywords: Drug release; Hollow spheres; Inclusion complexation; Stimuli-sensitivity; β-Cyclodextrin