title: Sorbitan ester organogels for transdermal delivery of sumatriptan.
abstract: The partial phase behavior, rheological, and drug release characteristics of an organogel (OG) composed of water, isooctane and sorbitan esters, sorbitan monopalmitate (Span-40) and poly(oxyethylene)sorbitan monostearate (Polysorbate-60) were studied. Phase diagrams showed decreasing areas of optically isotropic organogel region depending on the surfactant ratio, Kw and drug incorporation. The nonbirefringent, clear isotropic solution suggested the reverse micellar/microemulsion nature of the organogel without any molecular ordering. The increase in drug concentration in OGs leads to increase in the viscosity and sol-gel transition temperature (Tg). Fractal dimension (df) values calculated for different compositions suggested that the density of the tubular network increases with increasing drug concentration in OGs. The release rate of the drug from OGs was found to be non-Fickian through the dialysis membrane. The permeation rate of sumatriptan from pig skin was 0.231 mg/h/cm2 (781.9 nmol/h/cm2). The study indicates potential of OG as a reservoir system for transdermal drug delivery.
authors.affiliation: Pharmaceutical Research Project Laboratory, Department of Pharmaceutical Sciences, Dr. Harisingh Gour Vishwavidyalaya, Sagar, India. kupa@sify.com
authors.forename: Kamal K
authors.initials: KK
authors.lastname: Upadhyay
authors.forename: Chandraprabha
authors.initials: C
authors.lastname: Tiwari
authors.forename: Ajay J
authors.initials: AJ
authors.lastname: Khopade
authors.forename: Himadri B
authors.initials: HB
authors.lastname: Bohidar
authors.forename: Sanjay K
authors.initials: SK
authors.lastname: Jain
mesh_terms: D000279:Administration, Cutaneous; D000818:Animals; D004337:Drug Carriers; D004355:Drug Stability; D005782:Gels; D006601:Hexoses / Q000737:chemistry*; D066298:In Vitro Techniques; D010539:Permeability; D044367:Phase Transition; D011136:Polysorbates / Q000737:chemistry*; D012212:Rheology; D017366:Serotonin Receptor Agonists / Q000737:chemistry* / Q000493:pharmacokinetics; D012869:Skin Absorption / Q000187:drug effects; D018170:Sumatriptan / Q000737:chemistry* / Q000493:pharmacokinetics; D013501:Surface-Active Agents; D013552:Swine
chemical_list: D004337:Drug Carriers; D005782:Gels; D006601:Hexoses; D011136:Polysorbates; D017366:Serotonin Receptor Agonists; D013501:Surface-Active Agents; C061705:sorbitan monopalmitate; D018170:Sumatriptan