Bicontinuous water-AOT/Tween85-isopropyl myristate microemulsion: a new vehicle for transdermal delivery of cyclosporin A.
The purpose of this study was to investigate the influence of structure and composition of microemulsions (AOT/Tween85/isopropyl myristate/water) on their transdermal delivery potential of a lipophilic model drug (Cyclosporin A), and to compare the drug delivery potential of microemulsion to the suspension of drug in normal saline containing 20% ethanol. Their type and structure were examined by measuring surface tension, density, viscometry, and electric conductivity; the degree of agreement between the techniques was assessed. Transdermal flux of Cyclosporin A through rat skin was determined in vitro using Franz-type diffusion cells. Results of conducting, viscosity, and surface tension measurement confirmed the prediction transition to a bicontinuous structure. The microemulsions increased transdermal drug delivery of Cyclosporin A up to 10 times compared to the suspension. The increased transdermal delivery was found to be due mainly to water concentration and appeared to be dependent on the structure of the microemulsions.
Liu
Hongzhuo
H
School of Pharmaceutics, Pharmaceutical University of Shenyang, Shenyang 110016, People's Republic of China.
Li
Sanming
S
Wang
Yongjun
Y
Han
Fei
F
Dong
Yang
Y
D000279:Administration, Cutaneous; D000465:Algorithms; D000818:Animals; D055598:Chemical Phenomena; D002626:Chemistry, Pharmaceutical; D002627:Chemistry, Physical; D016572:Cyclosporine / Q000008:administration & dosage / Q000009:adverse effects / Q000737:chemistry*; D004553:Electric Conductivity; D004655:Emulsions / Q000737:chemistry; D005079:Excipients / Q000737:chemistry*; D007166:Immunosuppressive Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000737:chemistry*; D066298:In Vitro Techniques; D007509:Irritants; D009226:Myristates / Q000737:chemistry*; D011136:Polysorbates / Q000737:chemistry*; D011817:Rabbits; D051381:Rats; D012869:Skin Absorption; D013500:Surface Tension; D013501:Surface-Active Agents / Q000737:chemistry*; D014783:Viscosity; D014867:Water
D004655:Emulsions; D005079:Excipients; D007166:Immunosuppressive Agents; D007509:Irritants; D009226:Myristates; D011136:Polysorbates; D013501:Surface-Active Agents; D014867:Water; C008205:isopropyl myristate; D016572:Cyclosporine