A novel flow-programming setup based on the sequential injection principle is herein proposed for on-line monitoring of temporal events in cell permeation studies. The permeation unit consists of a Franz cell with its basolateral compartment mixed under mechanical agitation and thermostated at 37 °C. The apical compartment is replaced by commercially available Transwell inserts with a precultivated cell monolayer. The transport of drug substances across epithelial cells genetically modified with the P-glycoprotein membrane transporter (MDCKII-MDR1) is monitored on-line using rhodamine 123 as a fluorescent marker. The permeation kinetics of the marker is obtained in a fully automated mode by sampling minute volumes of solution from the basolateral compartment in short intervals (10 min) up to 4 h. The effect of a P-glycoprotein transporter inhibitor, verapamil as a model drug, on the efficiency of the marker transport across the cell monolayer is thoroughly investigated. The analytical features of the proposed flow method for cell permeation studies in real time are critically compared against conventional batch-wise procedures and microfluidic devices.

Department of Analytical Chemistry Faculty of Pharmacy in Hradec Králové Charles University Prague 500 05 Hradec Králové Czech Republic

Department of Pharmacology and Toxicology Faculty of Pharmacy in Hradec Králové Charles University Prague 500 05 Hradec Králové Czech Republic

FI TRACE group Department of Chemistry University of Balearic Islands Carretera de Valldemossa km 7 5 07122 Palma de Mallorca Spain

UCIBIO REQUIMTE Department of Chemistry Faculty of Pharmacy University of Porto 4051 401 Porto Portugal

References provided by Crossref.org

Sequential Injection Analysis for Automation and Evaluation of Drug Liberation Profiles: Clotrimazole Liberation Monitoring