Influence of surfactants additions on the absorption process of nifedipine in vitro.
The absorption process of nifedipine in aqueous NaCl solutions with additions of the following surfactants: egg lecithin, sodium lauryl sulphate and Tween-80 was studied in vitro. A flow-through apparatus containing a piece of small intestine (ileum) of a rat was used for the absorption rate measurements. The surfactants were added in two concentrations, i.e., below and above their critical micellar concentrations respectively. The small additions of the studied surfactants to the aqueous nifedipine solutions (i.e. in the concentrations below the critical micellar point) notably increased the absorption rate of nifedipine. However, when the mentioned surfactants were added in higher concentrations (i.e., above their critical micellar points), a important decrease of the absorption of nifedipine was observed.
Gadomska-Nowak
M
M
Department of Applied Pharmacy and Drug Design Technology, Medical Academy of Silesia, Sosnowiec, Poland.
Wojdak
H
H
D000818:Animals; D002121:Calcium Channel Blockers / Q000493:pharmacokinetics*; D007082:Ileum / Q000187:drug effects / Q000378:metabolism; D066298:In Vitro Techniques; D007408:Intestinal Absorption / Q000187:drug effects*; D009543:Nifedipine / Q000493:pharmacokinetics*; D019999:Pharmaceutical Solutions; D051381:Rats; D013501:Surface-Active Agents / Q000494:pharmacology*
D002121:Calcium Channel Blockers; D019999:Pharmaceutical Solutions; D013501:Surface-Active Agents; D009543:Nifedipine