title: Comparison of different water/oil microemulsions containing diclofenac sodium: preparation, characterization, release rate, and skin irritation studies.
abstract: The aim of the present study was to make a comparison of the in vitro release rate of diclofenac sodium (DS) from microemulsion (M) vehicles containing soybean oil, nonionic surfactants (Brij 58 and Span 80), and different alcohols (ethanol [E], isopropyl alcohol [I], and propanol [P]) as cosurfactant. The optimum surfactant:cosurfactant (S:CoS) weight ratios and microemulsion areas were detected by the aid of phase diagrams. Three microemulsion formulations were selected, and their physicochemical properties were examined for the pH, viscosity, and conductivity. According to the release rate of DS, M prepared with P showed the significantly highest flux value (0.059 +/- 0.018 mg/cm(2)/h) among all formulations (P < .05). The conductivity results showed that DS-loaded microemulsions have higher conductivity values (18.8-20.2 microsiemens/cm) than unloaded formulations (16.9-17.9 microsiemens/cm), and loading DS into the formulation had no negative effect on system stability. Moreover, viscosity measurements were examined as a function of shear rate, and Newtonian fluid characterization was observed for each microemulsion system. All formulations had appropriate observed pH values varying from 6.70 to 6.85 for topical application. A skin irritation study was performed with microemulsions on human volunteers, and no visible reaction was observed with any of the formulations. In conclusion, M prepared with P may be a more appropriate formulation than the other 2 formulations studied as drug carrier for topical application.
authors.affiliation: Pharmaceutical Biotechnology Department, Faculty of Pharmacy, University of Ege, 35100 Bornova-Izmir, Turkey. gulten.kantarci@ege.edu.tr
authors.forename: Gülten
authors.initials: G
authors.lastname: Kantarci
authors.forename: Işik
authors.initials: I
authors.lastname: Ozgüney
authors.forename: H Yeşim
authors.initials: HY
authors.lastname: Karasulu
authors.forename: Sevgi
authors.initials: S
authors.lastname: Arzik
authors.forename: Tamer
authors.initials: T
authors.lastname: Güneri
mesh_terms: D000433:1-Propanol / Q000737:chemistry; D019840:2-Propanol / Q000737:chemistry; D000279:Administration, Cutaneous; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage / Q000009:adverse effects / Q000737:chemistry*; D002592:Cetomacrogol / Q000737:chemistry; D002626:Chemistry, Pharmaceutical; D004008:Diclofenac / Q000008:administration & dosage / Q000009:adverse effects / Q000737:chemistry*; D004337:Drug Carriers; D004339:Drug Compounding; D004553:Electric Conductivity; D004655:Emulsions; D004890:Erythema / Q000139:chemically induced; D000431:Ethanol / Q000737:chemistry; D005260:Female; D006601:Hexoses; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008297:Male; D008956:Models, Chemical; D010316:Particle Size; D012867:Skin / Q000187:drug effects; D023422:Skin Irritancy Tests; D012995:Solubility; D013024:Soybean Oil / Q000008:administration & dosage / Q000009:adverse effects / Q000737:chemistry*; D013501:Surface-Active Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000737:chemistry*; D013678:Technology, Pharmaceutical / Q000379:methods; D014783:Viscosity; D014867:Water / Q000737:chemistry*
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D004337:Drug Carriers; D004655:Emulsions; D006601:Hexoses; D013501:Surface-Active Agents; D014867:Water; C018665:sorbitan monooleate; D004008:Diclofenac; D000431:Ethanol; D013024:Soybean Oil; D002592:Cetomacrogol; D000433:1-Propanol; D019840:2-Propanol