title: Cyclosporine A loaded SLNs: evaluation of cellular uptake and corneal cytotoxicity.
abstract: Cyclosporine A (CsA) loaded solid lipid nanoparticles (SLNs) for topical ophthalmic applications were prepared by high shear homogenization and ultrasound method using Compritol 888 ATO, Poloxamer 188 and Tween 80, to investigate the cellular uptake of rabbit corneal epithelial cells (RCE) and to evaluate the cytotoxicity. The size of the optimized formulation was 225.9+/-5.5 nm with a polydispersity index of 0.253+/-0.05. The zeta potential and entrapment efficiency was detected as -16.9+/-0.7 mV and 95.6%, respectively. The CsA release was found to be enzyme (lipase/co-lipase complex) dependent. SLNs were sterilized at 110 and 121 degrees C. The cytotoxicity was evaluated in vitro by means of RCE cells and was higher at 121 degrees C sterilization temperature, probably due to a supposed leakage of Tween 80 following lipid re-crystallization. The permeation and penetration of CsA across/into the corneal cells were evaluated using in vitro and ex vivo experiments. The cellular uptake was investigated by replacing CsA with the fluorescent dye Rhodamine B. The penetration enhancement properties were supported by confocal laser scanning microscopy analysis. The internalization of SLNs in cornea and in RCE cell lines was confirmed, pointing out the possibility of CsA targeting to the cornea.
authors: Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Ege, Izmir 35100, Turkey. evren.homan.gokce@ege.edu.tr
authors: Evren H
authors: EH
authors: Gokce
authors: Giuseppina
authors: G
authors: Sandri
authors: M Cristina
authors: MC
authors: Bonferoni
authors: Silvia
authors: S
authors: Rossi
authors: Franca
authors: F
authors: Ferrari
authors: Tamer
authors: T
authors: Güneri
authors: Carla
authors: C
authors: Caramella
mesh_terms: D000818:Animals; D002152:Calorimetry, Differential Scanning; D002470:Cell Survival / Q000187:drug effects; D003316:Corneal Diseases / Q000139:chemically induced* / Q000473:pathology*; D016572:Cyclosporine / Q000008:administration & dosage* / Q000009:adverse effects / Q000493:pharmacokinetics*; D004339:Drug Compounding; D004563:Electrochemistry; D004847:Epithelial Cells / Q000187:drug effects; D005079:Excipients; D005456:Fluorescent Dyes; D007166:Immunosuppressive Agents / Q000008:administration & dosage* / Q000009:adverse effects / Q000493:pharmacokinetics*; D066298:In Vitro Techniques; D018613:Microscopy, Confocal; D046529:Microscopy, Electron, Transmission; D009499:Neutral Red; D010316:Particle Size; D012235:Rhodamines; D013242:Sterilization; D013501:Surface-Active Agents; D013552:Swine
chemical_list: D005079:Excipients; D005456:Fluorescent Dyes; D007166:Immunosuppressive Agents; D012235:Rhodamines; D013501:Surface-Active Agents; D009499:Neutral Red; D016572:Cyclosporine; C029773:rhodamine B