Acta Pharm. 51 (2001) 173-181
The potential of liquisolid systems to improve the dissolution properties of water-insoluble agents was investigated using glibenclamide as a model drug. Several liquisolid tablet formulations were prepared using Aerosil and Avicel PH 102 as the carrier and coating materials, respectively. Polyethylene glycol 400 was used as the non-volatile liquid. Glibenclamide was added as solution and suspension in PEG 400. The effect of powder substrate composition and volume of the added liquid on the flowability and compressibility of the final admixture has been studied. In addition, the effect of the type of the coating material and drug concentration on the dissolution pattern of glibenclamide formulated in liquisolid tablets has been investigated. Liquisolid tablets exhibited superior in vitro release pattern as compared to those of marketed products. Maximum drug release was achieved when glibenclamide was dissolved in PEG 400 originally incorporated onto the powder substrate of the liquisolid systems. Based on the work presented in this paper, the higher dissolution rates displayed by the liquisolid tablets may also imply enhanced oral bioavailability of glibenclamide.
Keywords: liquisolid tablets, liquid vehicle, carrier powder, coating powder, glibenclamide, dissolution, drug concentration, excipient ratio, liquid load factor