title: In vitro controlled release of vitamin C from Ca/Al layered double hydroxide drug delivery system.
abstract: A new drug delivery system for vitamin C (VC), Ca/Al layered double hydroxide (LDH), is demonstrated in this work. VC anions were intercalated successfully in the Ca/Al LDH gallery by a coprecipitation method. The interlayer space of 9.8Å suggests that VC anions are vertical to the LDH layers in the form of interdigitated bilayer. The loading of VC in LDH is 36.4wt.%. The thermal stability of VC is significantly enhanced after intercalation. In vitro VC release results show that the release time of VC in a phosphate buffer at pH7.4 was significantly extended, and the maximal percentage of VC released is 80% of the total. The Avrami-Erofe'ev equation most satisfactorily explains the release kinetics of VC, which is that the release of VC is mainly dominated by the ion-exchange reaction.
authors.affiliation: College of Science, Hebei University of Engineering, Handan 056038, China; School of Chemistry and Chemical Engineering, Changzhou University, Changzhou, 213164, China. Electronic address: gxr_1320@sina.com.
authors.forename: Xiaorui
authors.initials: X
authors.lastname: Gao
authors.affiliation: School of Chemistry and Chemical Engineering, Changzhou University, Changzhou, 213164, China.
authors.forename: Le
authors.initials: L
authors.lastname: Chen
authors.affiliation: College of Science, Hebei University of Engineering, Handan 056038, China.
authors.forename: Juan
authors.initials: J
authors.lastname: Xie
authors.affiliation: College of Science, Hebei University of Engineering, Handan 056038, China.
authors.forename: Yaobing
authors.initials: Y
authors.lastname: Yin
authors.affiliation: College of Science, Hebei University of Engineering, Handan 056038, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Chang
authors.affiliation: College of Science, Hebei University of Engineering, Handan 056038, China.
authors.forename: Yancong
authors.initials: Y
authors.lastname: Duan
authors.affiliation: College of Science, Hebei University of Engineering, Handan 056038, China.
authors.forename: Nan
authors.initials: N
authors.lastname: Jiang
mesh_terms: D000535:Aluminum / Q000737:chemistry*; D001205:Ascorbic Acid / Q000737:chemistry*; D002118:Calcium / Q000737:chemistry*; D003692:Delayed-Action Preparations; D004337:Drug Carriers / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D006878:Hydroxides / Q000737:chemistry*; D007364:Intercalating Agents; D053758:Nanoparticles / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared; D013499:Surface Properties; D014961:X-Ray Diffraction
chemical_list: D003692:Delayed-Action Preparations; D004337:Drug Carriers; D006878:Hydroxides; D007364:Intercalating Agents; C031356:hydroxide ion; D000535:Aluminum; D001205:Ascorbic Acid; D002118:Calcium
keywords: Controlled release; Drug delivery system; Layered double hydroxide; Thermal stability; Vitamin C