Transcorneal and transscleral iontophoresis of dexamethasone phosphate using drug loaded hydrogel.
OBJECTIVE
To evaluate dexamethasone penetration to the eye after a short transcorneal and transscleral iontophoresis using a drug loaded hydrogel assembled on a portable iontophoretic device.


METHODS
Iontophoresis of dexamethasone phosphate was studied in healthy rabbits using drug loaded disposable HEMA hydrogel sponges and portable iontophoretic device. Corneal iontophoretic administration was performed with a current intensity of 1 mA for 1 and 4 min. Transconjunctival and transscleral iontophoresis were performed twice for 2 min at two near places in the pars-plana area, on the conjunctival membrane or directly on the sclera. Dexamethasone concentrations were assayed using HPLC.


RESULTS
Dexamethasone levels in the rabbit cornea after a single transcorneal iontophoresis for 1 min were up to 30 fold higher compared to those obtained after frequent eye drop instillation. Also, high drug concentrations were obtained in the retina and sclera 4 h after transscleral iontophoresis.


CONCLUSIONS
A short low current non-invasive iontophoretic treatment using dexamethasone-loaded hydrogels has potential clinical value in increasing drug penetration to the anterior and posterior segments of the eye.
Eljarrat-Binstock
Esther
E
Department of Medicinal Chemistry and Natural Products, School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 91120, Israel.
Raiskup
Frederik
F
Frucht-Pery
Joseph
J
Domb
Abraham J
AJ
D000818:Animals; D003315:Cornea / Q000378:metabolism*; D003907:Dexamethasone / Q000008:administration & dosage* / Q000031:analogs & derivatives; D016503:Drug Delivery Systems; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate / Q000008:administration & dosage*; D007478:Iontophoresis; D008297:Male; D011817:Rabbits; D012590:Sclera / Q000378:metabolism*
D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; C004180:dexamethasone 21-phosphate; D003907:Dexamethasone