title: Enteric coated magnetic HPMC capsules evaluated in human gastrointestinal tract by AC biosusceptometry.
abstract: OBJECTIVE
  To employ the AC Biosusceptometry (ACB) technique to evaluate in vitro and in vivo characteristics of enteric coated magnetic hydroxypropyl methylcellulose (HPMC) capsules and to image the disintegration process.
  
  
  METHODS
  HPMC capsules filled with ferrite (MnFe2O4) and coated with Eudragit were evaluated using USP XXII method and administered to fasted volunteers. Single and multisensor ACB systems were used to characterize the gastrointestinal (GI) motility and to determine gastric residence time (GRT), small intestinal transit time (SITT) and orocaecal transit time (OCTT). Mean disintegration time (t50) was quantified from 50% increase of pixels in the imaging area.
  
  
  RESULTS
  In vitro and in vivo performance of the magnetic HPMC capsules as well as the disintegration process were monitored using ACB systems. The mean disintegration time (t50) calculated for in vitro was 25+/-5 min and for in vivo was 13+/-5 min. In vivo also were determined mean values for GRT (55+/-19 min), SITT (185+/-82 min) and OCTT (240+/-88 min).
  
  
  CONCLUSIONS
  AC Biosusceptometry is a non-invasive technique originally proposed to monitoring pharmaceutical dosage forms orally administered and to image the disintegration process.
authors.affiliation: Departamento de Física e Biofísica, IBB, Universidade Estadual Paulista-UNESP, Distrito Rubião Jr, s/n, CXP 510, CEP 18618-000, Botucatu, São Paulo, Brazil.
authors.forename: Luciana A
authors.initials: LA
authors.lastname: Corá
authors.forename: Fernando G
authors.initials: FG
authors.lastname: Romeiro
authors.forename: Fabiano C
authors.initials: FC
authors.lastname: Paixão
authors.forename: Madileine F
authors.initials: MF
authors.lastname: Américo
authors.forename: Ricardo B
authors.initials: RB
authors.lastname: Oliveira
authors.forename: Oswaldo
authors.initials: O
authors.lastname: Baffa
authors.forename: José Ricardo A
authors.initials: JR
authors.lastname: Miranda
mesh_terms: D000328:Adult; D002214:Capsules; D002432:Cecum / Q000502:physiology; D005079:Excipients; D005260:Female; D005290:Ferric Compounds / Q000008:administration & dosage / Q000737:chemistry*; D005769:Gastrointestinal Motility / Q000502:physiology; D041981:Gastrointestinal Tract / Q000502:physiology*; D005772:Gastrointestinal Transit / Q000502:physiology; D006801:Humans; D006863:Hydrogen-Ion Concentration; D065347:Hypromellose Derivatives; D007080:Ileocecal Valve / Q000502:physiology; D007421:Intestine, Small / Q000502:physiology; D008280:Magnetics; D008297:Male; D008747:Methylcellulose / Q000031:analogs & derivatives* / Q000737:chemistry; D011109:Polymethacrylic Acids; D012995:Solubility; D013608:Tablets, Enteric-Coated
chemical_list: D002214:Capsules; D005079:Excipients; D005290:Ferric Compounds; D011109:Polymethacrylic Acids; D013608:Tablets, Enteric-Coated; C001215:ferrite; C038300:methylmethacrylate-methacrylic acid copolymer; D065347:Hypromellose Derivatives; D008747:Methylcellulose