In-vivo Buccal Delivery of Fluorescein Isothiocyanate–Dextran 4400 with Glycodeoxycholate as an Absorption Enhancer in Pigs

Abstract
Buccal delivery of fluorescein isothiocyanate labeled dextran 4400 (FD4) was investigated in-vivo in pigs. The delivery device consisted of an application chamber with a solution of FD4 and was adhered to the buccal mucosa for 4 h using an adhesive patch. A randomized crossover study including intravenous administration and buccal delivery without and with 10 mM sodium glycodeoxycholate (GDC) as absorption enhancer was performed in five pigs. After buccal administration, steady state plasma levels were rapidly reached. Coadministration of 10 mM GDC increased the absolute bioavailability of FD4 from 1.8 +/- 0.5% to 12.7 +/- 2.0%. Since FD4 is a macromolecular and hydrophilic compound such as peptide and protein drugs, buccal delivery would provide an adequate alternative to the parenteral administration of these drugs.