Mucoadhesive liposomal delivery systems: the choice of coating material.
OBJECTIVE
Development of liposomal mucoadhesive drug delivery system, which is able to improve the bioavailability of poorly absorbed oral drugs by prolonging their gastric and intestinal residence time, through facilitating the intimate contact of the delivery system with the absorption membrane.


METHODS
Liposomes containing model drug atenolol were prepared by the modified ethanol injection method. Liposomes containing atenolol were coated by different mucoadhesive polymers, for example, chitosan, Carbopol 974P, Eudragit L100, and Eudragit S100, to optimize the choice of coating material. The delivery systems were tested for their in vitro mucoadhesiveness.


RESULTS
Liposomes prepared by the ethanol injection method were of satisfactory size (around 100 nm, before coating). Through the coating of liposomes in the presence of unentrapped material, the entrapment efficiency for drug was increased. In vitro mucoadhesive test confirmed the mucoadhesive properties of the coated layer for all tested polymers; however, Eudragit S100-coated liposomes were superior to other coating materials.


CONCLUSIONS
Eudragit coating appeared to be an optimal polymer choice. These preliminary data indicate that polymer-coated mucoadhesive liposomes are able to carry sufficient amount of drug and to remain attached to the intestinal mucosa for a sufficient period of time to enable prolonged absorption of entrapped drug.


CONCLUSIONS
While keeping in mind that the in vivo conditions may vary with the in vitro ones, we may recommend the system described in our work for possible oral delivery of peptides and phytochemicals.
The School of Pharmaceutical and Biomedical Sciences, Pokhara University, Lekhnath, Nepal.
Pankaj Ranjan
PR
Karn
Zeljka
Z
Vanić
Ivan
I
Pepić
Nataša
N
Skalko-Basnet
D001262:Atenolol / Q000008:administration & dosage / Q000032:analysis / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid; D016503:Drug Delivery Systems; D008081:Liposomes / Q000737:chemistry*; D010316:Particle Size; D011109:Polymethacrylic Acids / Q000737:chemistry; D012995:Solubility
D008081:Liposomes; D011109:Polymethacrylic Acids; C038300:methylmethacrylate-methacrylic acid copolymer; D001262:Atenolol