title: Drug reservoir function of human amniotic membrane.
abstract: OBJECTIVE
  The aim of the study was the quantitative pharmacokinetic evaluation of drug release from pretreated amniotic membrane (AM) in vitro.
  
  
  METHODS
  Cryopreserved AM pieces soaked in 3% ofloxacin ophthalmic solution were mounted in vertical Franz-diffusion cell system equipped with autosampler. In vitro release of ofloxacin was determined by quantitative absorbance measurement carried out with a UV spectrophotometer (wavelength 287 nm). Three groups were created according to the duration of soaking: 60 (Group 1), 120 (Group 2), and 180 (Group 3) minutes. Released amount of ofloxacin pro 1 cm(2) of AM (μg/cm(2)) was calculated in the period of 1 to 450 min.
  
  
  RESULTS
  Ofloxacin was detectable in the acceptor phase 1 min after mounting in all groups. Until 120 min, rapid increase of released ofloxacin could be observed. From 120 to 450 min, the amount of released ofloxacin showed a slower increasing pattern. Released ofloxacin in Group 1 was significantly lower than in Group 2 after 90 min (19.4±10.4 μg/cm(2), 51.6±20.7 μg/cm(2), respectively, P=0.044). In Group 3, cumulative drug release was higher than in Group at all timepoints. No significant difference could be demonstrated between Groups 2 and 3 at only 1 min timepoint.
  
  
  CONCLUSIONS
  Significant ofloxacin reservoir capacity of a single human amniotic layer could be demonstrated in vitro. AM acted as an ofloxacin slow release device for upto 7 h in vitro, depending on the duration of pretreatment of AM. Individual pretreatment of AM could increase beneficial effects of AM transplantation, especially in infectious keratitis.
authors.affiliation: Department of Ophthalmology, Semmelweis University, Budapest, Hungary. miklosresch@gmail.com
authors.forename: Miklós D
authors.initials: MD
authors.lastname: Resch
authors.forename: Béla E
authors.initials: BE
authors.lastname: Resch
authors.forename: Eszter
authors.initials: E
authors.lastname: Csizmazia
authors.forename: László
authors.initials: L
authors.lastname: Imre
authors.forename: János
authors.initials: J
authors.lastname: Németh
authors.forename: Piroska
authors.initials: P
authors.lastname: Szabó-Révész
authors.forename: Erzsébet
authors.initials: E
authors.lastname: Csányi
mesh_terms: D000650:Amnion / Q000378:metabolism* / Q000637:transplantation; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000493:pharmacokinetics*; D015194:Diffusion Chambers, Culture; D006801:Humans; D015242:Ofloxacin / Q000008:administration & dosage / Q000493:pharmacokinetics*; D009883:Ophthalmic Solutions; D010539:Permeability; D013056:Spectrophotometry, Ultraviolet; D013997:Time Factors
chemical_list: D000900:Anti-Bacterial Agents; D009883:Ophthalmic Solutions; D015242:Ofloxacin