title: Preparation and characterization of enteric microparticles by coacervation.
abstract: The aim of this study was to produce cinnarizine loaded Eudragit(®) L100-55 microparticles by coacervation technique in order to achieve pH responsive drug release using hydroxypropyl methycellulose (HPMC) as stabilizer. The effect of enteric polymer: HPMC ratio on properties of microparticles was investigated with regard to particle size distribution, morphology, yield, encapsulation efficiency, in vitro drug release profiles and interaction between cinnarizine and Eudragit(®) L100-55. High drug encapsulation efficiency was seen in all microparticles. Particle diameter increased when the enteric polymer content was higher relative to HPMC. In vitro dissolution studies demonstrated that the drug release from the microparticles was dependent upon enteric polymer: HPMC ratio and particle size distribution. At the ratio of at least 3.75:1 of enteric polymer: HPMC, drug release was suppressed most significantly in low pH (hydrochloric acid as medium) while rapid drug release was observed in pH 7.4.
authors.affiliation: Department of Pharmacy, Health and Well Being, Faculty of Applied Sciences, University of Sunderland, City Campus, Sunderland, UK.
authors.forename: Steffi
authors.initials: S
authors.lastname: Thomas
authors.forename: Yin Ning
authors.initials: YN
authors.lastname: Chong
authors.forename: Cheng Shu
authors.initials: CS
authors.lastname: Chaw
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry; D002152:Calorimetry, Differential Scanning; D002626:Chemistry, Pharmaceutical; D002936:Cinnarizine / Q000008:administration & dosage* / Q000737:chemistry; D006634:Histamine H1 Antagonists / Q000008:administration & dosage*; D006863:Hydrogen-Ion Concentration; D065347:Hypromellose Derivatives; D008747:Methylcellulose / Q000031:analogs & derivatives / Q000737:chemistry; D010316:Particle Size; D012995:Solubility; D017550:Spectroscopy, Fourier Transform Infrared; D013678:Technology, Pharmaceutical
chemical_list: D000180:Acrylic Resins; C446821:Eudragit L100-55; D006634:Histamine H1 Antagonists; D002936:Cinnarizine; D065347:Hypromellose Derivatives; D008747:Methylcellulose